Diabetes Prevalence Among Racial-Ethnic Minority Group Members With Severe Mental Illness Taking Antipsychotics: Double Jeopardy?

PubMed

Mangurian, Christina; Keenan, Walker; Newcomer, John W; Vittinghoff, Eric; Creasman, Jennifer M; Schillinger, Dean

2017-08-01

This study assessed differences in diabetes prevalence based on race-ethnicity among people with severe mental illnesses. This retrospective cohort study examined diabetes prevalence in 2009 among California Medicaid enrollees with severe mental illness who were screened for diabetes (N=19,364). Poisson regression assessed differences in diabetes prevalence by race-ethnicity. The sample was standardized to the U.S. The overall prevalence of diabetes was 32.0%. The adjusted prevalence for all minority groups with severe mental illness, except for Asians, was significantly higher than for whites (1.21-1.28 adjusted prevalence ratios). With inverse probability weighting to reduce selection bias captured by measured factors, estimated prevalence of diabetes among screened participants was 27.3%. The prevalence of diabetes in minority groups with severe mental illness was significantly higher than among whites with severe mental illness. Mental health administrators should implement universal diabetes screening with specific outreach efforts targeting minority populations with severe mental illness.

“Attacks” or “Whistling”: Impact of Questionnaire Wording on Wheeze Prevalence Estimates

PubMed Central

Pescatore, Anina M.; Spycher, Ben D.; Beardsmore, Caroline S.; Kuehni, Claudia E.

2015-01-01

Background Estimates of prevalence of wheeze depend on questionnaires. However, wording of questions may vary between studies. We investigated effects of alternative wording on estimates of prevalence and severity of wheeze, and associations with risk factors. Methods White and South Asian children from a population-based cohort (UK) were randomly assigned to two groups and followed up at one, four and six years (1998, 2001, 2003). Parents were asked either if their child ever had “attacks of wheeze” (attack group, N=535), or “wheezing or whistling in the chest” (whistling group, N=2859). All other study aspects were identical, including questions about other respiratory symptoms. Results Prevalence of wheeze ever was lower in the attack group than in the whistling group for all surveys (32 vs. 40% in white children aged one year, p<0.001). Prevalence of other respiratory symptoms did not differ between groups. Wheeze tended to be more severe in the attack group. The strength of association with risk factors was comparable in the two groups. Conclusions The wording of questions on wheeze can affect estimates of prevalence, but has less impact on measured associations with risk factors. Question wording is a potential source of between-study-heterogeneity in meta-analyses. PMID:26114296

State-level estimates of childhood obesity prevalence in the United States corrected for report bias.

PubMed

Long, M W; Ward, Z J; Resch, S C; Cradock, A L; Wang, Y C; Giles, C M; Gortmaker, S L

2016-10-01

State-specific obesity prevalence data are critical to public health efforts to address the childhood obesity epidemic. However, few states administer objectively measured body mass index (BMI) surveillance programs. This study reports state-specific childhood obesity prevalence by age and sex correcting for parent-reported child height and weight bias. As part of the Childhood Obesity Intervention Cost Effectiveness Study (CHOICES), we developed childhood obesity prevalence estimates for states for the period 2005-2010 using data from the 2010 US Census and American Community Survey (ACS), 2003-2004 and 2007-2008 National Survey of Children's Health (NSCH) (n=133 213), and 2005-2010 National Health and Nutrition Examination Surveys (NHANES) (n=9377; ages 2-17). Measured height and weight data from NHANES were used to correct parent-report bias in NSCH using a non-parametric statistical matching algorithm. Model estimates were validated against surveillance data from five states (AR, FL, MA, PA and TN) that conduct censuses of children across a range of grades. Parent-reported height and weight resulted in the largest overestimation of childhood obesity in males ages 2-5 years (NSCH: 42.36% vs NHANES: 11.44%). The CHOICES model estimates for this group (12.81%) and for all age and sex categories were not statistically different from NHANES. Our modeled obesity prevalence aligned closely with measured data from five validation states, with a 0.64 percentage point mean difference (range: 0.23-1.39) and a high correlation coefficient (r=0.96, P=0.009). Estimated state-specific childhood obesity prevalence ranged from 11.0 to 20.4%. Uncorrected estimates of childhood obesity prevalence from NSCH vary widely from measured national data, from a 278% overestimate among males aged 2-5 years to a 44% underestimate among females aged 14-17 years. This study demonstrates the validity of the CHOICES matching methods to correct the bias of parent-reported BMI data and

An estimate of the prevalence of epilepsy in Sub-Saharan Africa: A systematic analysis.

PubMed

Paul, Abigail; Adeloye, Davies; George-Carey, Rhiannon; Kolčić, Ivana; Grant, Liz; Chan, Kit Yee

2012-12-01

Epilepsy is a leading serious neurological condition worldwide and has particularly significant physical, economic and social consequences in Sub-Saharan Africa. This paper aims to contribute to the understanding of epilepsy prevalence in this region and how this varies by age and sex so as to inform understanding of the disease characteristics as well as the development of infrastructure, services and policies. A parallel systematic analysis of Medline, Embase and Global Health returned 32 studies that satisfied pre-defined quality criteria. Relevant data was extracted, tabulated and analyzed. We modelled the available information and used the UN population figures for Africa to determine the age-specific and overall burden of epilepsy. Active epilepsy was estimated to affect 4.4 million people in Sub-Saharan Africa, whilst lifetime epilepsy was estimated to affect 5.4 million. The prevalence of active epilepsy peaks in the 20-29 age group at 11.5/1000 and again in the 40-49 age group at 8.2/1000. The lowest prevalence value of 3.1/1000 is seen in the 60+ age group. This binomial pattern is also seen in both men and women, with the second peak more pronounced in women at 14.6/1000. The high prevalence of epilepsy, especially in young adults, has important consequences for both the workforce and community structures. An estimation of disease burden would be a beneficial outcome of further research, as would research into appropriate methods of improving health care for and tackling discrimination against people with epilepsy.

Prevalence of rheumatic regional pain syndromes in Latin-American indigenous groups: a census study based on COPCORD methodology and syndrome-specific diagnostic criteria.

PubMed

Alvarez-Nemegyei, José; Peláez-Ballestas, Ingris; Goñi, Mario; Julián-Santiago, Flor; García-García, Conrado; Quintana, Rosana; Silvestre, Adriana M R; García-Olivera, Imelda; Mathern, Nora A; Loyola-Sanchez, Adalberto; Conti, Silvana; Sanabria, Alvaro J; Pons-Estel, Bernardo A

2016-07-01

This study assessed the overall and specific prevalence of the main rheumatic regional pain syndromes (RRPS) in four Latin-American indigenous groups. A Community Oriented Program for Control of Rheumatic Diseases (COPCORD) methodology-based census study was performed in 4240 adults (participation rate: 78.88 %) in four indigenous groups: Chontal (Oaxaca, Mexico, n = 124), Mixteco (Oaxaca, Mexico; n = 937), Maya-Yucateco (Yucatán, Mexico; n = 1523), and Qom (Rosario, Argentina; n = 1656). Subjects with musculoskeletal pain were identified using a cross-cultural, validated COPCORD questionnaire administered by bilingual personnel, and reviewed by general practitioners or rheumatologists using standardized case definitions for the 12 most frequent RRPS. The overall prevalence of RRPS was confirmed in 239 cases (5.64 %, 95 % CI: 4.98-6.37). The prevalence in each group was Chontal n = 19 (15.32 %, 95 % CI: 10.03-22.69); Maya-Yucateco n = 165 (10.83 %, 95 % CI: 9.37-12.49); Qom n = 48 (2.90 %, 95 % CI: 2.19-3.82); and Mixteco n = 7 (0.75 %, 95 % CI: 0.36-1.53). In the whole sample, the syndrome-specific prevalence was rotator cuff tendinopathy: 1.98 % (95 % CI: 1.60-2.45); lateral epicondylalgia: 0.83 % (95 % CI: 0.59-1.15); medial epicondylalgia: 0.73 % (95 % CI: 0.52-1.04); biceps tendinopathy: 0.71 % (95 % CI: 0.50-1.01); anserine syndrome: 0.64 % (95 % CI: 0.44-0.92); inferior heel pain: 0.61 % (95 % CI: 0.42-0.90); trochanteric syndrome: 0.49 % (95 % CI: 0.25-0.64); de Quervain's tendinopathy: 0.45 % (95 % CI: 0.29-0.70); trigger finger: 0.42 % (95 % CI: 0.27-0.67); carpal tunnel syndrome: 0.28 % (95 % CI: 0.16-0.49); Achilles tendinopathy (insertional): 0.12 % (95 % CI: 0.05-0.28); and Achilles tendinopathy (non-insertional): 0.07 % (95 % CI: 0.02-0.21). Leaving aside the comparison between Maya-Yucateco and Chontal groups (p = 0.18), we found significant differences (p < 0.001) in

Variation of a test’s sensitivity and specificity with disease prevalence

PubMed Central

Leeflang, Mariska M.G.; Rutjes, Anne W.S.; Reitsma, Johannes B.; Hooft, Lotty; Bossuyt, Patrick M.M.

2013-01-01

Background: Anecdotal evidence suggests that the sensitivity and specificity of a diagnostic test may vary with disease prevalence. Our objective was to investigate the associations between disease prevalence and test sensitivity and specificity using studies of diagnostic accuracy. Methods: We used data from 23 meta-analyses, each of which included 10–39 studies (416 total). The median prevalence per review ranged from 1% to 77%. We evaluated the effects of prevalence on sensitivity and specificity using a bivariate random-effects model for each meta-analysis, with prevalence as a covariate. We estimated the overall effect of prevalence by pooling the effects using the inverse variance method. Results: Within a given review, a change in prevalence from the lowest to highest value resulted in a corresponding change in sensitivity or specificity from 0 to 40 percentage points. This effect was statistically significant (p < 0.05) for either sensitivity or specificity in 8 meta-analyses (35%). Overall, specificity tended to be lower with higher disease prevalence; there was no such systematic effect for sensitivity. Interpretation: The sensitivity and specificity of a test often vary with disease prevalence; this effect is likely to be the result of mechanisms, such as patient spectrum, that affect prevalence, sensitivity and specificity. Because it may be difficult to identify such mechanisms, clinicians should use prevalence as a guide when selecting studies that most closely match their situation. PMID:23798453

Sex- and Age-Adjusted Population Analysis of Prevalence Estimates for Hidradenitis Suppurativa in the United States.

PubMed

Garg, Amit; Kirby, Joslyn S; Lavian, Jonathan; Lin, Gloria; Strunk, Andrew

2017-08-01

The true prevalence of hidradenitis suppurativa (HS) is unknown. To establish standardized overall and group-specific prevalence estimates for HS in the United States. This retrospective analysis included a demographically heterogeneous population-based sample of more than 48 million unique patients across all US census regions. As of October 27, 2016, a total of 47 690 patients with HS were identified using electronic health record data. Standardized overall point prevalence for HS and sex-, age-, and race-specific prevalence estimates of HS in the general US population. Of the 47 690 patients with HS (26.2% men and 73.8% women), the overall HS prevalence in the US population sample was 0.10%, or 98 per 100 000 persons (95% CI, 97-99 per 100 000 persons). The adjusted prevalence in women was 137 per 100 000 (95% CI, 136-139 per 100 000), more than twice that of men (58 per 100 000; 95% CI, 57-59 per 100 000; P < .001). The prevalence of HS was highest among patients aged 30 to 39 years (172 per 100 000; 95% CI, 169-275 per 100 000) compared with all other age groups (range, 15-150 per 100 000; P < .001). Adjusted HS prevalences among African American (296 per 100 000; 95% CI, 291-300 per 100 000) and biracial (218 per 100 000; 95% CI, 202-235 per 100 000) patients were more than 3-fold and 2-fold greater, respectively, than that among white patients (95 per 100 000; 95% CI, 94-96 per 100 000; P < .001). Hidradenitis suppurativa is an uncommon, but not rare, disease in the United States that disproportionately affects female patients, young adults, and African American and biracial patients.

Bayesian inference for disease prevalence using negative binomial group testing

PubMed Central

Pritchard, Nicholas A.; Tebbs, Joshua M.

2011-01-01

Group testing, also known as pooled testing, and inverse sampling are both widely used methods of data collection when the goal is to estimate a small proportion. Taking a Bayesian approach, we consider the new problem of estimating disease prevalence from group testing when inverse (negative binomial) sampling is used. Using different distributions to incorporate prior knowledge of disease incidence and different loss functions, we derive closed form expressions for posterior distributions and resulting point and credible interval estimators. We then evaluate our new estimators, on Bayesian and classical grounds, and apply our methods to a West Nile Virus data set. PMID:21259308

Bayesian estimation of true prevalence, sensitivity and specificity of three diagnostic tests for detection of Escherichia coli O157 in cattle feces.

PubMed

Ekong, Pius S; Sanderson, Michael W; Bello, Nora M; Noll, Lance W; Cernicchiaro, Natalia; Renter, David G; Bai, Jianfa; Nagaraja, T G

2017-12-01

Cattle are a reservoir for Escherichia coli O157 and they shed the pathogen in their feces. Fecal contaminants on the hides can be transferred onto carcasses during processing at slaughter plants, thereby serving as a source of foodborne infection in humans. The detection of E. coli O157 in cattle feces is based on culture, immunological, and molecular methods We evaluated the diagnostic sensitivity and specificity of one culture- and two PCR-based tests for the detection of E. coli O157 in cattle feces, and its true prevalence using a Bayesian implementation of latent class models. A total of 576 fecal samples were collected from the floor of pens of finishing feedlot cattle in the central United States during summer 2013. Samples were enriched and subjected to detection of E. coli O157 by culture (immunomagnetic separation, plating on a selective medium, latex agglutination, and indole testing), conventional PCR (cPCR), and multiplex quantitative PCR (mqPCR). The statistical models assumed conditional dependence of the PCR tests and high specificity for culture (mode=99%; 5th percentile=97%). Prior estimates of test parameters were elicited from three experts. Estimated posterior sensitivity (posterior median and 95% highest posterior density intervals) of culture, cPCR, and mqPCR was 49.1% (44.8-53.4%), 59.7% (55.3-63.9%), and 97.3% (95.1-99.0%), respectively. Estimated posterior specificity of culture, cPCR, and mqPCR were 98.7% (96.8-99.8%), 94.1% (87.4-99.1%), and 94.8% (84.1-99.9%), respectively. True prevalence was estimated at 91.3% (88.1-94.2%). There was evidence of a weak conditional dependence between cPCR and mqPCR amongst test positive samples, but no evidence of conditional dependence amongst test negative samples. Sensitivity analyses showed that overall our posterior inference was rather robust to the choice of priors, except for inference on specificity of mqPCR, which was estimated with considerable uncertainty. Our study evaluates performance

Estimating the prevalence of female genital mutilation in Portugal.

PubMed

Teixeira, A L; Lisboa, M

2016-10-01

Due to globalized migratory processes, female genital mutilation/cutting (FGM/C) has spread to other countries, including countries in Europe, where, with a few exceptions, it remains a concealed problem. To the authors' knowledge, this is the first national extensive study to estimate the prevalence of FGM/C in Portugal. Prevalence estimation. Using extrapolation of country-of-origin prevalence data and the 2011 Census data, this study estimated: the prevalence of FGM/C in Portugal among women of reproductive age (15-49 years) and among all women aged ≥15 years; and the number of girls aged <15 years living in Portugal who have undergone or will probably undergo FGM/C. It is estimated that 6576 women aged ≥15 years living in Portugal have undergone FGM/C, with cases distributed unevenly throughout the national territory. In addition, it is estimated that 1830 girls aged <15 years living in Portugal have undergone or are likely to undergo FGM/C. This study estimated that more than 6000 women living in Portugal have undergone FGM/C, and many girls remain at risk. These two groups need different types of interventions. Awareness of the number and geographical dispersion of cases of FGM/C will enable more informed and targeted definition of public health policies for protection of females who have undergone or are at risk of undergoing FGM/C. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

A multilevel model for cardiovascular disease prevalence in the US and its application to micro area prevalence estimates.

PubMed

Congdon, Peter

2009-01-30

Estimates of disease prevalence for small areas are increasingly required for the allocation of health funds according to local need. Both individual level and geographic risk factors are likely to be relevant to explaining prevalence variations, and in turn relevant to the procedure for small area prevalence estimation. Prevalence estimates are of particular importance for major chronic illnesses such as cardiovascular disease. A multilevel prevalence model for cardiovascular outcomes is proposed that incorporates both survey information on patient risk factors and the effects of geographic location. The model is applied to derive micro area prevalence estimates, specifically estimates of cardiovascular disease for Zip Code Tabulation Areas in the USA. The model incorporates prevalence differentials by age, sex, ethnicity and educational attainment from the 2005 Behavioral Risk Factor Surveillance System survey. Influences of geographic context are modelled at both county and state level, with the county effects relating to poverty and urbanity. State level influences are modelled using a random effects approach that allows both for spatial correlation and spatial isolates. To assess the importance of geographic variables, three types of model are compared: a model with person level variables only; a model with geographic effects that do not interact with person attributes; and a full model, allowing for state level random effects that differ by ethnicity. There is clear evidence that geographic effects improve statistical fit. Geographic variations in disease prevalence partly reflect the demographic composition of area populations. However, prevalence variations may also show distinct geographic 'contextual' effects. The present study demonstrates by formal modelling methods that improved explanation is obtained by allowing for distinct geographic effects (for counties and states) and for interaction between geographic and person variables. Thus an appropriate

A multilevel model for cardiovascular disease prevalence in the US and its application to micro area prevalence estimates

PubMed Central

Congdon, Peter

2009-01-01

Background Estimates of disease prevalence for small areas are increasingly required for the allocation of health funds according to local need. Both individual level and geographic risk factors are likely to be relevant to explaining prevalence variations, and in turn relevant to the procedure for small area prevalence estimation. Prevalence estimates are of particular importance for major chronic illnesses such as cardiovascular disease. Methods A multilevel prevalence model for cardiovascular outcomes is proposed that incorporates both survey information on patient risk factors and the effects of geographic location. The model is applied to derive micro area prevalence estimates, specifically estimates of cardiovascular disease for Zip Code Tabulation Areas in the USA. The model incorporates prevalence differentials by age, sex, ethnicity and educational attainment from the 2005 Behavioral Risk Factor Surveillance System survey. Influences of geographic context are modelled at both county and state level, with the county effects relating to poverty and urbanity. State level influences are modelled using a random effects approach that allows both for spatial correlation and spatial isolates. Results To assess the importance of geographic variables, three types of model are compared: a model with person level variables only; a model with geographic effects that do not interact with person attributes; and a full model, allowing for state level random effects that differ by ethnicity. There is clear evidence that geographic effects improve statistical fit. Conclusion Geographic variations in disease prevalence partly reflect the demographic composition of area populations. However, prevalence variations may also show distinct geographic 'contextual' effects. The present study demonstrates by formal modelling methods that improved explanation is obtained by allowing for distinct geographic effects (for counties and states) and for interaction between geographic and

Estimation and Projection of Prevalence of Colorectal Cancer in Iran, 2015-2020.

PubMed

Vardanjani, Hossein Molavi; Haghdoost, AliAkbar; Bagheri-Lankarani, Kamran; Hadipour, Maryam

2018-01-01

Population aging and more prevalent westernized lifestyle would be expected to result in a markedly rising burden of colorectal cancer (CRC) in the future years. The aim of this study is to estimate the limited-time prevalence of CRC in Iran between 2015 and 2020. Aggregated CRC incidence data were extracted from the Iranian national cancer registry (IR.NCR) reports for 2003-2009 and from GLOBOCAN-2012 database for 2012. Incidence trends were analyzed by age groups, genders, histopathologic, and topographic subtypes to estimate annual percentage changes. Incidence was projected for 2020. The prevalence was estimated applying an adopted version of a previously introduced equation to estimate limited-time prevalence based on the incidence and survival data. Monte Carlo sensitivity analyses were applied to estimate 95% uncertainty levels (ULs). In each scenario, incidence, survival, annual percentage changes, and completeness of case ascertainment at IR.NCR were replaced under pre-assumed distributions. Number of estimated within 1, 2-3 and 4-5-year CRC patients in 2015 were 13676 (95% UL: 10051-18807), 20964 (15835-28268), and 14485 (11188-19293), respectively. Estimated 5-year prevalence for 2020 (99463; 75150-134744) was 2.03 times of that for 2015. Highest 5-year prevalence was estimated in ages 55-59 for females and 75 + for males. Adenocarcinoma (41376; 31227 55898) was the most prevalent histologic subtype. The most prevalent tumor location was colon (30822, 23262-41638). A substantial growth in the prevalence of CRC survivors is highly expected for future years in Iran. Establishment of specialized institutes is highly recommended to provide medical and especially social supports for Iranian CRC survivors.

Group Sequential Testing of the Predictive Accuracy of a Continuous Biomarker with Unknown Prevalence

PubMed Central

Koopmeiners, Joseph S.; Feng, Ziding

2015-01-01

Group sequential testing procedures have been proposed as an approach to conserving resources in biomarker validation studies. Previously, Koopmeiners and Feng (2011) derived the asymptotic properties of the sequential empirical positive predictive value (PPV) and negative predictive value curves, which summarize the predictive accuracy of a continuous marker, under case-control sampling. A limitation of their approach is that the prevalence can not be estimated from a case-control study and must be assumed known. In this manuscript, we consider group sequential testing of the predictive accuracy of a continuous biomarker with unknown prevalence. First, we develop asymptotic theory for the sequential empirical PPV and NPV curves when the prevalence must be estimated, rather than assumed known in a case-control study. We then discuss how our results can be combined with standard group sequential methods to develop group sequential testing procedures and bias-adjusted estimators for the PPV and NPV curve. The small sample properties of the proposed group sequential testing procedures and estimators are evaluated by simulation and we illustrate our approach in the context of a study to validate a novel biomarker for prostate cancer. PMID:26537180

Estimating disease prevalence in two-phase studies.

PubMed

Alonzo, Todd A; Pepe, Margaret Sullivan; Lumley, Thomas

2003-04-01

Disease prevalence is ideally estimated using a 'gold standard' to ascertain true disease status on all subjects in a population of interest. In practice, however, the gold standard may be too costly or invasive to be applied to all subjects, in which case a two-phase design is often employed. Phase 1 data consisting of inexpensive and non-invasive screening tests on all study subjects are used to determine the subjects that receive the gold standard in the second phase. Naive estimates of prevalence in two-phase studies can be biased (verification bias). Imputation and re-weighting estimators are often used to avoid this bias. We contrast the forms and attributes of the various prevalence estimators. Distribution theory and simulation studies are used to investigate their bias and efficiency. We conclude that the semiparametric efficient approach is the preferred method for prevalence estimation in two-phase studies. It is more robust and comparable in its efficiency to imputation and other re-weighting estimators. It is also easy to implement. We use this approach to examine the prevalence of depression in adolescents with data from the Great Smoky Mountain Study.

Estimating diabetes prevalence by small area in England.

PubMed

Congdon, Peter

2006-03-01

Diabetes risk is linked to both deprivation and ethnicity, and so prevalence will vary considerably between areas. Prevalence differences may partly account for geographic variation in health performance indicators for diabetes, which are based on age standardized hospitalization or operation rates. A positive correlation between prevalence and health outcomes indicates that the latter are not measuring only performance. A regression analysis of prevalence rates according to age, sex and ethnicity from the Health Survey for England (HSE) is undertaken and used (together with census data) to estimate diabetes prevalence for 354 English local authorities and 8000 smaller areas (electoral wards). An adjustment for social factors is based on a prevalence gradient over area-deprivation quintiles. A Bayesian estimation approach is used allowing simple inclusion of evidence on prevalence from other or historical sources. The estimated prevalent population in England is 1.5 million (188 000 type 1 and 1.341 million type 2). At strategic health authority (StHA) level, prevalence varies from 2.4 (Thames Valley) to 4 per cent (North East London). The prevalence estimates are used to assess variations between local authorities in adverse hospitalization indicators for diabetics and to assess the relationship between diabetes-related mortality and prevalence. In particular, rates of diabetic ketoacidosis (DKA) and coma are positively correlated with prevalence, while diabetic amputation rates are not. The methodology developed is applicable to developing small-area-prevalence estimates for a range of chronic diseases, when health surveys assess prevalence by demographic categories. In the application to diabetes prevalence, there is evidence that performance indicators as currently calculated are not corrected for prevalence.

Estimating the geographical distribution of the prevalence of the metabolic syndrome in young Mexicans.

PubMed

Murguía-Romero, Miguel; Jiménez-Flores, Rafael; Villalobos-Molina, Rafael; Méndez-Cruz, Adolfo René

2012-09-01

The geographical distribution of the metabolic syndrome (MetS) prevalence in young Mexicans (aged 17-24 years) was estimated stepwise starting from its prevalence based on the body mass index (BMI) in a study of 3,176 undergraduate students of this age group from Mexico City. To estimate the number of people with MetS by state, we multiplied its prevalence derived from the BMI range found in the Mexico City sample by the BMI proportions (range and state) obtained from the Mexico 2006 national survey on health and nutrition. Finally, to estimate the total number of young people with MetS in Mexico, its prevalence by state was multiplied by the share of young population in each state according to the National Population and Housing Census 2010. Based on these figures, we estimated the national prevalence of MetS at 15.8%, the average BMI at 24.1 (standard deviation = 4.2), and the prevalence of overweight people (BMI ≥25) of that age group at 39.0%. These results imply that 2,588,414 young Mexicans suffered from MetS in 2010. The Yucatan peninsula in the south and the Sonora state in the north showed the highest rates of MetS prevalence. The calculation of the MetS prevalence by BMI range in a sample of the population, and extrapolating it using the BMI proportions by range of the total population, was found to be a useful approach. We conclude that the BMI is a valuable public health tool to estimate MetS prevalence in the whole country, including its geographical distribution.

Estimating the global prevalence of transthyretin familial amyloid polyneuropathy

PubMed Central

Waddington‐Cruz, Márcia; Botteman, Marc F.; Carter, John A.; Chopra, Avijeet S.; Hopps, Markay; Stewart, Michelle; Fallet, Shari; Amass, Leslie

2018-01-01

ABSTRACT Introduction: This study sought to estimate the global prevalence of transthyretin familial amyloid polyneuropathy (ATTR‐FAP). Methods: Prevalence estimates and information supporting prevalence calculations was extracted from records yielded by reference‐database searches (2005–2016), conference proceedings, and nonpeer reviewed sources. Prevalence was calculated as prevalence rate multiplied by general population size, then extrapolated to countries without prevalence estimates but with reported cases. Results: Searches returned 3,006 records; 1,001 were fully assessed and 10 retained, yielding prevalence for 10 “core” countries, then extrapolated to 32 additional countries. ATTR‐FAP prevalence in core countries, extrapolated countries, and globally was 3,762 (range 3639–3884), 6424 (range, 1,887–34,584), and 10,186 (range, 5,526–38,468) persons, respectively. Discussion: The mid global prevalence estimate (10,186) approximates the maximum commonly accepted estimate (5,000–10,000). The upper limit (38,468) implies potentially higher prevalence. These estimates should be interpreted carefully because contributing evidence was heterogeneous and carried an overall moderate risk of bias. This highlights the requirement for increasing rare‐disease epidemiological assessment and clinician awareness. Muscle Nerve 57: 829–837, 2018 PMID:29211930

Serotype specific polymerase chain reaction identifies a higher prevalence of streptococcus mutans serotype k and e in a random group of children with dental caries from the Southern region of India.

PubMed

Rao, Arun Prasad; Austin, Ravi David

2014-07-01

The development of dental caries has been associated with the oral prevalence of Streptococcus mutans. Four serotypes of S. mutans have been reported, namely serotype c, e, f, and k that are classified based on the composition and linkages of cell wall polysaccharides, response to physiological reactions, sero-specificity and 16s rRNA homology. Although the oral prevalence of S. mutans serotype c in Indian subjects with or without caries is known, the prevalence of the other three serotypes, e, f, and k are not known. Hence in this study, we have investigated the occurrence of the e, f, and k serotypes in children with or without caries within the age group of 6-12 years. Genomic DNA isolated from whole saliva of caries active (CA) and caries free (CF) groups were first screened for the presence of S. mutans by strain specific polymerase chain reaction (PCR). Those samples that tested positive for the presence of S. mutans were further analyzed by serotype specific PCR to identify the prevalence of the serotypes. Strain specific PCR indicated a higher prevalence of S. mutans in CA group (80%) relative to CF group (43%). Further analysis of the S. mutans positive samples in both groups indicated a higher prevalence of serotype k and e, followed by serotype f in CA group. The present data clearly establishes a novel S. mutans serotype prevalence hierarchy in children from this region, compared with those that have been reported elsewhere. Besides, the data are also clinically significant as the occurrence of serotype k has been associated with infective endocarditis.

Taenia solium porcine cysticercosis in Madagascar: Comparison of immuno-diagnostic techniques and estimation of the prevalence in pork carcasses traded in Antananarivo city.

PubMed

Porphyre, V; Betson, M; Rabezanahary, H; Mboussou, Y; Zafindraibe, N J; Rasamoelina-Andriamanivo, H; Costard, S; Pfeiffer, D U; Michault, A

2016-03-30

Taenia solium cysticercosis was reported in official veterinary and medical statistics to be highly prevalent in pigs and humans in Madagascar, but few estimates are available for pigs. This study aimed to estimate the seroprevalence of porcine cysticercosis among pigs slaughtered in Antananarivo abattoirs. Firstly, the diagnostic performance of two antigen-ELISA techniques (B158B60 Ag-ELISA and HP10 Ag-ELISA) and an immunoblotting method were compared with meat inspection procedures on a sample of pigs suspected to be infected with (group 1; n=250) or free of (group 2; n=250) T. solium based on direct veterinary inspection in Madagascar. Sensitivity and specificity of the antigen ELISAs were then estimated using a Bayesian approach for detection of porcine cysticercosis in the absence of a gold standard. Then, a third set of pig sera (group 3, n=250) was randomly collected in Antananarivo slaughterhouses and tested to estimate the overall prevalence of T. solium contamination in pork meat traded in Antananarivo. The antigen ELISAs showed a high sensitivity (>84%), but the B158B60 Ag-ELISA appeared to be more specific than the HP10 Ag-ELISA (model 1: 95% vs 74%; model 2: 87% vs 71%). The overall prevalence of porcine cysticercosis in Antananarivo slaughterhouses was estimated at 2.3% (95% credibility interval [95%CrI]: 0.09-9.1%) to 2.6% (95%CrI: 0.1-10.3%) depending on the model and priors used. Since the sample used in this study is not representative of the national pig population, village-based surveys and longitudinal monitoring at slaughter are needed to better estimate the overall prevalence, geographical patterns and main risk factors for T. solium contamination, in order to improve control policies. Copyright © 2015 Elsevier B.V. All rights reserved.

Trends in depression prevalence in the USA from 2005 to 2015: widening disparities in vulnerable groups.

PubMed

Weinberger, A H; Gbedemah, M; Martinez, A M; Nash, D; Galea, S; Goodwin, R D

2018-06-01

Major depression is associated with significant disability, morbidity, and mortality. The current study estimated trends in the prevalence of major depression in the US population from 2005 to 2015 overall and by demographic subgroups. Data were drawn from the National Survey on Drug Use and Health (NSDUH), an annual cross-sectional study of US persons ages 12 and over (total analytic sample N = 607 520). Past-year depression prevalence was examined annually among respondents from 2005 to 2015. Time trends in depression prevalence stratified by survey year were tested using logistic regression. Data were re-analyzed stratified by age, gender, race/ethnicity, income, and education. Depression prevalence increased significantly in the USA from 2005 to 2015, before and after controlling for demographics. Increases in depression were significant for the youngest and oldest age groups, men, and women, Non-Hispanic White persons, the lowest income group, and the highest education and income groups. A significant year × demographic interaction was found for age. The rate of increase in depression was significantly more rapid among youth relative to all older age groups. The prevalence of depression increased significantly in the USA from 2005 to 2015. The rate of increase in depression among youth was significantly more rapid relative to older groups. Further research into understanding the macro level, micro level, and individual factors that are contributing to the increase in depression, including factors specific to demographic subgroups, would help to direct public health prevention and intervention efforts.

Rheumatoid arthritis prevalence in Quebec.

PubMed

Bernatsky, Sasha; Dekis, Alaa; Hudson, Marie; Pineau, Christian A; Boire, Gilles; Fortin, Paul R; Bessette, Louis; Jean, Sonia; Chetaille, Ann L; Belisle, Patrick; Bergeron, Louise; Feldman, Debbie Ehrmann; Joseph, Lawrence

2014-12-19

To estimate rheumatoid arthritis (RA) prevalence in Quebec using administrative health data, comparing across regions. Cases of RA were ascertained from physician billing and hospitalization data, 1992-2008. We used three case definitions: 1) ≥ 2 billing diagnoses, submitted by any physician, ≥ 2 months apart, but within 2 years; 2) ≥ 1 diagnosis, by a rheumatologist; 3) ≥1 hospitalization diagnosis (all based on ICD-9 code 714, and ICD-10 code M05). We combined data across these three case definitions, using Bayesian hierarchical latent class models to estimate RA prevalence, adjusting for the imperfect sensitivity and specificity of the data. We compared urban versus rural regions. Using our case definitions and no adjustment for error, we defined 75,760 cases for an over-all RA prevalence of 9.9 per thousand residents. After adjusting for the imperfect sensitivity and specificity of our case definition algorithms, we estimated Quebec RA prevalence at 5.6 per 1000 females and 4.1 per 1000 males. The adjusted RA prevalence estimates for older females were the highest for any demographic group (9.9 cases per 1,000), and were similar in rural and urban regions. In younger males and females, and in older males, RA prevalence estimates were lower in rural versus urban areas. Without adjustment for error inherent in administrative databases, RA prevalence in Quebec was approximately 1%, while adjusted estimates are approximately half that. The lower prevalence in rural areas, seen for most demographic groups, may suggest either true regional variations in RA risk, or under-ascertainment of cases in rural Quebec.

Prevalence of Mycoplasma genitalium in different population groups: systematic review andmeta-analysis.

PubMed

Baumann, Lukas; Cina, Manuel; Egli-Gany, Dianne; Goutaki, Myrofora; Halbeisen, Florian S; Lohrer, Gian-Reto; Ali, Hammad; Scott, Pippa; Low, Nicola

2018-06-01

Mycoplasma genitalium is a common cause of non-gonococcal non-chlamydial urethritis and cervicitis. Testing of asymptomatic populations has been proposed, but prevalence in asymptomatic populations is not well established. We aimed to estimate the prevalence of M. genitalium in the general population, pregnant women, men who have sex with men (MSM), commercial sex workers (CSWs) and clinic-based samples, METHODS: We searched Embase, Medline, IndMED, African Index Medicus and LILACS from 1 January 1991 to 12 July 2016 without language restrictions. We included studies with 500 participants or more. Two reviewers independently screened and selected studies and extracted data. We examined forest plots and conducted random-effects meta-analysis to estimate prevalence, if appropriate. Between-study heterogeneity was examined using the I 2 statistic and meta-regression. Of 3316 screened records, 63 were included. In randomly selected samples from the general population, the summary prevalence was 1.3% (95% CI 1.0% to 1.8%, I 2 41.5%, three studies, 9091 people) in countries with higher levels of development and 3.9% (95% CI 2.2 to 6.7, I 2 89.2%, three studies, 3809 people) in countries with lower levels. Prevalence was similar in women and men (P=0.47). In clinic based samples, prevalence estimates were higher, except in asymptomatic patients (0.8%, 95% CI 0.4 to 1.4, I 2 0.0%, three studies, 2889 people). Summary prevalence estimates were, in the following groups: pregnant women 0.9% (95% CI 0.6% to 1.4%, I 2 0%, four studies, 3472 people), MSM in the community 3.2% (95% CI 2.1 to 5.1, I 2 78.3%, five studies, 3012 people) and female CSWs in the community 15.9% (95% CI 13.5 to 18.9, I 2 79.9%, four studies, 4006 people). This systematic review can inform testing guidelines for M. genitalium . The low estimated prevalence of M. genitalium in the general population, pregnant women and asymptomatic attenders at clinics does not support expansion of testing to these

Serotype specific polymerase chain reaction identifies a higher prevalence of streptococcus mutans serotype k and e in a random group of children with dental caries from the Southern region of India

PubMed Central

Rao, Arun Prasad; Austin, Ravi David

2014-01-01

Background: The development of dental caries has been associated with the oral prevalence of Streptococcus mutans. Four serotypes of S. mutans have been reported, namely serotype c, e, f, and k that are classified based on the composition and linkages of cell wall polysaccharides, response to physiological reactions, sero-specificity and 16s rRNA homology. Although the oral prevalence of S. mutans serotype c in Indian subjects with or without caries is known, the prevalence of the other three serotypes, e, f, and k are not known. Hence in this study, we have investigated the occurrence of the e, f, and k serotypes in children with or without caries within the age group of 6-12 years. Materials and Methods: Genomic DNA isolated from whole saliva of caries active (CA) and caries free (CF) groups were first screened for the presence of S. mutans by strain specific polymerase chain reaction (PCR). Those samples that tested positive for the presence of S. mutans were further analyzed by serotype specific PCR to identify the prevalence of the serotypes. Results: Strain specific PCR indicated a higher prevalence of S. mutans in CA group (80%) relative to CF group (43%). Further analysis of the S. mutans positive samples in both groups indicated a higher prevalence of serotype k and e, followed by serotype f in CA group. Conclusion: The present data clearly establishes a novel S. mutans serotype prevalence hierarchy in children from this region, compared with those that have been reported elsewhere. Besides, the data are also clinically significant as the occurrence of serotype k has been associated with infective endocarditis. PMID:25191062

Satellite-based Estimates of Ambient Air Pollution and Global Variations in Childhood Asthma Prevalence

NASA Technical Reports Server (NTRS)

Anderson, H. Ross; Butland, Barbara K.; Donkelaar, Aaron Matthew Van; Brauer, Michael; Strachan, David P.; Clayton, Tadd; van Dingenen, Rita; Amann, Marcus; Brunekreef, Bert; Cohen, Aaron;

Tuberculosis among elderly Chinese in residential homes: tuberculin reactivity and estimated prevalence.

PubMed

Woo, J; Chan, H S; Hazlett, C B; Ho, S C; Chan, R; Sham, A; Davies, P D

1996-01-01

Objectives of this study were to determine the prevalence of positive tuberculin reactivity and associated factors among elderly nursing home residents in a population with a relatively high tuberculosis notification rate, to estimate the prevalence of active tuberculosis, and to assess tuberculin reactivity as a screening tool. A stratified, disproportional, randomized cluster sample of residents was selected and the Mantoux test (using 0.1 ml of 5 tuberculin units of purified protein derivative of tuberculin) carried out. All subjects with a positive test had a chest X-ray followed by sputum smear and culture if the X-ray was abnormal. Sputum examination was also carried out in a random sample of controls, matched for age and gender, drawn from subjects with a negative Mantoux test. Information regarding medical history, tobacco smoking habits, symptoms related to tuberculosis, and communal eating habits were gathered. Also anthropometric data were collected. Sixteen nursing homes in the catchment area of a major district hospital in Hong Kong comprising 587 residents (136 men, 451 women, mean age 80 +/- 8 years) participated in this study. The weighted prevalence of tuberculin reactivity was 43.8%. It was higher in men, among those who took their meals in a common area, in the younger age group, and in those with no previous history of hospitalization. No association was found between prevalence and duration of residence, smoking, skinfold thickness, past medical history, or any relevant symptoms. Following radiological and sputum examination, the estimated prevalence of active tuberculosis ranged from 1.2 to 2.6%. The sensitivity of the tuberculin test was 86, the specificity 30%. The prevalence of active tuberculosis in nursing homes in Hong Kong is high, but it is unclear whether cross-infection or poor health of the residents is the major contributing factor. Tuberculin skin testing does not appear to be a useful screening method in this population.

Estimated amount of 24-hour urine sodium excretion is positively correlated with stomach and breast cancer prevalence in Korea.

PubMed

Park, Jung Hwan; Kim, Yong Chul; Koo, Ho Seok; Oh, Se Won; Kim, Suhnggwon; Chin, Ho Jun

2014-09-01

Stomach cancer is one of the most common cancers in Korea. The aim of this study was to identify the association between the prevalence of cancer, particularly stomach cancer, and the amount of 24-hr urine sodium excretion estimated from spot urine specimens. The study included 19,083 subjects who took part in the Korean National Health and Nutritional Examination Survey between 2009 and 2011. The total amount of urine sodium excreted in a 24-hr period was estimated by using two equations based on the values for spot urine sodium and creatinine. In subjects who had an estimated 24-hr urine sodium excretion of more than two standard deviations above the mean (group 2), the prevalence of stomach cancer was higher than in subjects with lower 24-hr sodium excretion (group 1). By using the Tanaka equation to estimate it, the prevalence of stomach cancer was 0.6% (114/18,331) in group 1, whereas it was 1.6% (9/568) in group 2 (P=0.006). By using the Korean equation, the prevalence was 0.6% (115/18,392) in group 1, and 1.6% in group 2 (8/507) (P=0.010). By using the Tanaka equation, breast cancer in women is more prevalent in group 2 (1.9%, 6/324) than group 1 (0.8%, 78/9,985, P=0.039). Higher salt intake, as defined by the estimated amount of 24-hr urine sodium excretion, is positively correlated with a higher prevalence of stomach or breast cancer in the Korean population.

Prevalence of vaginitis in different age groups among females in Greece.

PubMed

Sianou, Argiri; Galyfos, George; Moragianni, Dimitra; Baka, Stavroula

2017-08-01

Patients with vaginitis were classified into four groups: Group A (prepubertal under-aged females); Group B (pubertal under-aged females); Group C (reproductive age adult females); Group D (postmenopausal adult females). All vaginal specimens underwent microscopy, amine testing, Gram staining and culturing. Overall, 163 patients were included (33, 14, 81 and 35 patients, respectively). The most common infection was bacterial vaginosis (BV), followed by Ureaplasma infection, aerobic vaginitis (AV) and candidiasis. The most common AV-associated organism was Escherichia coli and the most common BV-associated organism was Gardnerella vaginalis. AV was more frequent in Group A, BV in Group C and Ureaplasma infections in Groups C/D. Decreased lactobacilli concentrations were associated with BV in fertile patients (Groups B-C). Although presentation of vaginitis is similar among females of different age in Greece, type and prevalence of pathogens differ. Normal vaginal flora changes are associated with higher risk of vaginitis in specific age groups. Impact Statement The worldwide incidence of reproductive tract infections has been increasing, with specific pathogens being associated with significant risk of morbidity and complications. However, literature data on the distribution of such infections in different age groups is limited. Therefore, the aim of this study was to provide data on the prevalence and causes of vaginitis in adult and non-adult females of all ages. This study has shown that although presentation of vaginitis is similar among females of different age groups and menstrual status in Greece, type and prevalence of responsible pathogens are different among groups. Changes in normal vaginal flora seem to be associated with higher risk of vaginitis in specific age-groups as well. These findings could contribute in adjusting diagnostic and therapeutic strategies for each age group according to the prevailing pathogens. Further research on antibiotic

A study of the prevalence and clinical significance of venom-specific IgE.

PubMed

Zora, J A; Swanson, M C; Yunginger, J W

1988-01-01

The prevalence of unrecognized Hymenoptera-venom sensitization, assessed by venom skin tests (VSTs) in adults with no history of adverse reactions to sting, has been as high as 12% in previous epidemiologic studies. To assess further the clinical importance of positive VSTs in such individuals, we skin tested 33 subjects stung in the field during the preceding 12 months without reaction, and 33 persons who denied being stung in the preceding 3 years. Among the recently stung group, 12/33 had at least one positive VST (greater than or equal to 2+) at 1.0 microgram/ml, whereas 5/33 had positive VST at 0.1 microgram/ml. In contrast, only 2/33 nonstung subjects had positive VST at 1.0 microgram/ml, and none were positive at 0.1 microgram/ml. To estimate, prospectively, the sensitization rate after insect stings, we studied a third group of 11 nonsensitive patients with negative skin tests to Hymenoptera. After a deliberate in-hospital honeybee sting, only 1/11 developed a persistently positive honeybee VST. From among the three groups, we then performed nine sting challenges in eight patients with positive VSTs, and all stings were tolerated without significant reaction. We also measured IgE antibodies to Hymenoptera venoms in random blood bank donors. During April to May, 2/216 sera contained elevated venom-specific IgE antibodies, whereas 14/201 sera collected from October to November contained elevated venom-specific IgE antibodies. We conclude that a small but appreciable portion of the population has venom-specific IgE antibodies and that the prevalence is seasonably variable. Our data indicate that persons recently stung without significant reaction contribute to this group but that only a small portion of this group is at risk for a systemic reaction with a future sting.

The prevalence of inflammatory back pain: population-based estimates from the US National Health and Nutrition Examination Survey, 2009-10.

PubMed

Weisman, Michael H; Witter, James P; Reveille, John D

2013-03-01

To estimate the current US inflammatory back pain (IBP) prevalence using four published case definitions. Analysis of an IBP data collection instrument specifically designed for the 2009-10 National Health and Nutrition Examination Survey. Subjects were 5103 US adults ages 20-69 with complete data. IBP prevalence as determined by Calin et al criteria, European Spondylarthropathy Study Group (ESSG) criteria, and Berlin criteria 8a and 7b. Age-adjusted US prevalence of IBP by Calin criteria was 5.0% (95% CI 4.2% to 5.8%). Prevalence of IBP was 5.6% (95% CI 4.7% to 6.5%) by ESSG criteria, and 5.8% (95% CI 5.2% to 6.4%) and 6.0% (95% CI 4.9% to 7.1%) by Berlin Criteria 8a and 7b, respectively. IBP prevalence did not differ significantly by age groups or between men and women. IBP prevalence was significantly lower among non-Hispanic black persons compared with non-Hispanic white persons for the Calin and ESSG IBP criteria. For the ESSG and Berlin 7b criteria, non-Hispanic white persons had significantly higher IBP prevalences compared with Mexican Americans. IBP is associated with spondyloarthritis. Awareness of the prevalence of IBP may be useful for planning future epidemiological studies as well as development and validation of diagnostic and classification criteria for specific clinically defined diseases.

Accuracy of Herdsmen Reporting versus Serologic Testing for Estimating Foot-and-Mouth Disease Prevalence

PubMed Central

Handel, Ian G.; Tanya, Vincent N.; Hamman, Saidou M.; Nfon, Charles; Bergman, Ingrid E.; Malirat, Viviana; Sorensen, Karl J.; Bronsvoort, Barend M. de C.

2014-01-01

Herdsman-reported disease prevalence is widely used in veterinary epidemiologic studies, especially for diseases with visible external lesions; however, the accuracy of such reports is rarely validated. Thus, we used latent class analysis in a Bayesian framework to compare sensitivity and specificity of herdsman reporting with virus neutralization testing and use of 3 nonstructural protein ELISAs for estimates of foot-and-mouth disease (FMD) prevalence on the Adamawa plateau of Cameroon in 2000. Herdsman-reported estimates in this FMD-endemic area were comparable to those obtained from serologic testing. To harness to this cost-effective resource of monitoring emerging infectious diseases, we suggest that estimates of the sensitivity and specificity of herdsmen reporting should be done in parallel with serologic surveys of other animal diseases. PMID:25417556

Anaemia prevalence over time in Indonesia: estimates from the 1997, 2000, and 2008 Indonesia Family Life Surveys.

PubMed

Barkley, Jonathan S; Kendrick, Katherine L; Codling, Karen; Muslimatun, Siti; Pachón, Helena

2015-01-01

To summarize anaemia prevalence data for children, women, and men using data from the second, third and fourth waves of the Indonesia Family Life Surveys (IFLS), which were conducted in 1997/8, 2000, and 2007/8, respectively. Anaemia prevalence was determined for children 0 to 5 years, 5 to 12 years, 12 to 15 years, non-pregnant women at least 15 years, pregnant women at least 15 years, and men at least 15 years, based on haemoglobin adjusted for altitude and smoking status. Compared with 1997/8 estimates, anaemia prevalence estimates were lower in 2007/8 for all groups, with the greatest relative decline occurring in children 5 to 12 years (25.4%). Trend analysis found anaemia significantly declined over the survey years for all groups (χ² p=0.005 for pregnant women, χ² p<0.001 for all other groups). IFLS anaemia estimates for different population groups decreased between 1997/8 and 2007/8 and were consistent with estimates from Southeast Asia, and with other studies conducted in Indonesia. While the prevalence of anaemia consistently decreased in all groups, anaemia remains a moderate public health problem for children 0 to 5 years, children 5 to 12 years, and non-pregnant and pregnant women.

Can administrative health utilisation data provide an accurate diabetes prevalence estimate for a geographical region?

PubMed

Chan, Wing Cheuk; Papaconstantinou, Dean; Lee, Mildred; Telfer, Kendra; Jo, Emmanuel; Drury, Paul L; Tobias, Martin

2018-05-01

To validate the New Zealand Ministry of Health (MoH) Virtual Diabetes Register (VDR) using longitudinal laboratory results and to develop an improved algorithm for estimating diabetes prevalence at a population level. The assigned diabetes status of individuals based on the 2014 version of the MoH VDR is compared to the diabetes status based on the laboratory results stored in the Auckland regional laboratory result repository (TestSafe) using the New Zealand diabetes diagnostic criteria. The existing VDR algorithm is refined by reviewing the sensitivity and positive predictive value of the each of the VDR algorithm rules individually and as a combination. The diabetes prevalence estimate based on the original 2014 MoH VDR was 17% higher (n = 108,505) than the corresponding TestSafe prevalence estimate (n = 92,707). Compared to the diabetes prevalence based on TestSafe, the original VDR has a sensitivity of 89%, specificity of 96%, positive predictive value of 76% and negative predictive value of 98%. The modified VDR algorithm has improved the positive predictive value by 6.1% and the specificity by 1.4% with modest reductions in sensitivity of 2.2% and negative predictive value of 0.3%. At an aggregated level the overall diabetes prevalence estimated by the modified VDR is 5.7% higher than the corresponding estimate based on TestSafe. The Ministry of Health Virtual Diabetes Register algorithm has been refined to provide a more accurate diabetes prevalence estimate at a population level. The comparison highlights the potential value of a national population long term condition register constructed from both laboratory results and administrative data. Copyright © 2018 Elsevier B.V. All rights reserved.

Satellite-based Estimates of Ambient Air Pollution and Global Variations in Childhood Asthma Prevalence

PubMed Central

Butland, Barbara K.; van Donkelaar, Aaron; Brauer, Michael; Strachan, David P.; Clayton, Tadd; van Dingenen, Rita; Amann, Marcus; Brunekreef, Bert; Cohen, Aaron; Dentener, Frank; Lai, Christopher; Lamsal, Lok N.; Martin, Randall V.; One, ISAAC Phase

2012-01-01

Background: The effect of ambient air pollution on global variations and trends in asthma prevalence is unclear. Objectives: Our goal was to investigate community-level associations between asthma prevalence data from the International Study of Asthma and Allergies in Childhood (ISAAC) and satellite-based estimates of particulate matter with aerodynamic diameter < 2.5 µm (PM2.5) and nitrogen dioxide (NO2), and modelled estimates of ozone. Methods: We assigned satellite-based estimates of PM2.5 and NO2 at a spatial resolution of 0.1° × 0.1° and modeled estimates of ozone at a resolution of 1° × 1° to 183 ISAAC centers. We used center-level prevalence of severe asthma as the outcome and multilevel models to adjust for gross national income (GNI) and center- and country-level sex, climate, and population density. We examined associations (adjusting for GNI) between air pollution and asthma prevalence over time in centers with data from ISAAC Phase One (mid-1900s) and Phase Three (2001–2003). Results: For the 13- to 14-year age group (128 centers in 28 countries), the estimated average within-country change in center-level asthma prevalence per 100 children per 10% increase in center-level PM2.5 and NO2 was –0.043 [95% confidence interval (CI): –0.139, 0.053] and 0.017 (95% CI: –0.030, 0.064) respectively. For ozone the estimated change in prevalence per parts per billion by volume was –0.116 (95% CI: –0.234, 0.001). Equivalent results for the 6- to 7-year age group (83 centers in 20 countries), though slightly different, were not significantly positive. For the 13- to 14-year age group, change in center-level asthma prevalence over time per 100 children per 10% increase in PM2.5 from Phase One to Phase Three was –0.139 (95% CI: –0.347, 0.068). The corresponding association with ozone (per ppbV) was –0.171 (95% CI: –0.275, –0.067). Conclusion: In contrast to reports from within-community studies of individuals exposed to traffic pollution

Estimating population prevalence of psychiatric conditions by small area with applications to analysing outcome and referral variations.

PubMed

Congdon, Peter

2006-12-01

This paper considers the development of estimates of mental illness prevalence for small areas and applications in explaining psychiatric outcomes and in assessing service provision. Estimates of prevalence are based on a logistic regression analysis of two national studies that provides model based estimates of relative morbidity risk by demographic, socio-economic and ethnic group for major psychiatric conditions; household/marital and area status also figure in the regression. Relative risk estimates are used, along with suitably disaggregated census populations, to make prevalence estimates for 354 English local authorities (LAs). Two applications are considered: the first involves analysis of variations in schizophrenia referrals and suicide mortality over English LAs that takes account of prevalence differences, and the second involves assessing hospital referral and bed use in relation to prevalence (for ages 16-74) for a case study area, Waltham Forest in NE London.

Assessing the dependence of sensitivity and specificity on prevalence in meta-analysis

PubMed Central

Li, Jialiang; Fine, Jason P.

2011-01-01

We consider modeling the dependence of sensitivity and specificity on the disease prevalence in diagnostic accuracy studies. Many meta-analyses compare test accuracy across studies and fail to incorporate the possible connection between the accuracy measures and the prevalence. We propose a Pearson type correlation coefficient and an estimating equation–based regression framework to help understand such a practical dependence. The results we derive may then be used to better interpret the results from meta-analyses. In the biomedical examples analyzed in this paper, the diagnostic accuracy of biomarkers are shown to be associated with prevalence, providing insights into the utility of these biomarkers in low- and high-prevalence populations. PMID:21525421

Recent HIV prevalence trends among pregnant women and all women in sub-Saharan Africa: implications for HIV estimates.

PubMed

Eaton, Jeffrey W; Rehle, Thomas M; Jooste, Sean; Nkambule, Rejoice; Kim, Andrea A; Mahy, Mary; Hallett, Timothy B

2014-11-01

National population-wide HIV prevalence and incidence trends in sub-Saharan Africa (SSA) are indirectly estimated using HIV prevalence measured among pregnant women attending antenatal clinics (ANC), among other data. We evaluated whether recent HIV prevalence trends among pregnant women are representative of general population trends. Serial population-based household surveys in 13 SSA countries. We calculated HIV prevalence trends among all women aged 15-49 years and currently pregnant women between surveys conducted from 2003 to 2008 (period 1) and 2009 to 2012 (period 2). Log-binomial regression was used to test for a difference in prevalence trend between the two groups. Prevalence among pregnant women was age-standardized to represent the age distribution of all women. Pooling data for all countries, HIV prevalence declined among pregnant women from 6.5 [95% confidence interval (CI) 5.3-7.9%] to 5.3% (95% CI 4.2-6.6%) between periods 1 and 2, whereas it remained unchanged among all women at 8.4% (95% CI 8.0-8.9%) in period 1 and 8.3% (95% CI 7.9-8.8%) in period 2. Prevalence declined by 18% (95% CI -9-38%) more in pregnant women than nonpregnant women. Estimates were similar in Western, Eastern, and Southern regions of SSA; none were statistically significant (P>0.05). HIV prevalence decreased significantly among women aged 15-24 years while increasing significantly among women 35-49 years, who represented 29% of women but only 15% of pregnant women. Age-standardization of prevalence in pregnant women did not reconcile the discrepant trends because at older ages prevalence was lower among pregnant women than nonpregnant women. As HIV prevalence in SSA has shifted toward older, less-fertile women, HIV prevalence among pregnant women has declined more rapidly than prevalence in women overall. Interpretation of ANC prevalence data to inform national HIV estimates should account for both age-specific fertility patterns and HIV-related sub-fertility.

Evidence-based design recommendations for prevalence studies on multimorbidity: improving comparability of estimates.

PubMed

Holzer, Barbara M; Siebenhuener, Klarissa; Bopp, Matthias; Minder, Christoph E

2017-03-07

In aging populations, multimorbidity causes a disease burden of growing importance and cost. However, estimates of the prevalence of multimorbidity (prevMM) vary widely across studies, impeding valid comparisons and interpretation of differences. With this study we pursued two research objectives: (1) to identify a set of study design and demographic factors related to prevMM, and (2) based on (1), to formulate design recommendations for future studies with improved comparability of prevalence estimates. Study data were obtained through systematic review of the literature. UsingPubMed/MEDLINE, Embase, CINAHL, Web of Science, BIOSIS, and Google Scholar, we looked for articles with the terms "multimorbidity," "comorbidity," "polymorbidity," and variations of these published in English or German in the years 1990 to 2011. We selected quantitative studies of the prevalence of multimorbidity (two or more chronic medical conditions) with a minimum sample size of 50 and a study population with a majority of Caucasians. Our database consisted of prevalence estimates in 108 age groups taken from 45 studies. To assess the effects of study design variables, we used meta regression models. In 58% of the studies, there was only one age group, i.e., no stratification by age. The number of persons per age group ranged from 136 to 5.6 million. Our analyses identified the following variables as highly significant: "mean age," "number of age groups", and "data reporting quality" (all p < 0.0001). "Setting," "disease classification," and "number of diseases in the classification" were significant (0.01 < p ≤ 0.03), and "data collection period" and "data source" were non-significant. A separate analysis showed that prevMM was significantly higher in women than men (sign test, p = 0.0015). Comparable prevalence estimates are urgently needed for realistic description of the magnitude of the problem of multimorbidity. Based on the results of our analyses of variables

Current and projected prevalence of arterial hypertension in sub-Saharan Africa by sex, age and habitat: an estimate from population studies.

PubMed

Twagirumukiza, Marc; De Bacquer, Dirk; Kips, Jan G; de Backer, Guy; Stichele, Robert Vander; Van Bortel, Luc M

2011-07-01

In sub-Saharan Africa (SSA), data on hypertension prevalence in terms of urban or rural and sex difference are lacking, heterogeneous or contradictory. In addition, there are no accurate estimates of hypertension burden. To estimate the age-specific and sex-specific prevalence of arterial hypertension in SSA in urban and rural adult populations. We searched for population studies, conducted from 1998 through 2008 in SSA. We extracted data from selected studies on available prevalences and used a logistic regression model to estimate all age/sex/habitat (urban/rural)/country-specific prevalences for SSA up to 2008 and 2025. On the basis of the United Nations Population Fund data for 2008 and predictions for 2025, we estimated the number of hypertensives in both years. Seventeen studies pertaining to 11 countries were analysed. The overall prevalence rate of hypertension in SSA for 2008 was estimated at 16.2% [95% confidence interval (CI) 14.1-20.3], ranging from 10.6% in Ethiopia to 26.9% in Ghana. The estimated prevalence was 13.7% in rural areas, 20.7% in urban areas, 16.8% in males, and 15.7% in women. The total number of hypertensives in SSA was estimated at 75 million (95% CI 65-93 million) in 2008 and at 125.5 million (95% CI 111.0-162.9 million) by 2025. The estimated number of hypertensives in 2008 is nearly four times higher than the last (2005) estimate of the World Health Organization Regional Office for Africa. Prevalences were significantly higher in urban than in rural populations. Population data are lacking in many countries underlining the need for national surveys.

Improvements in prevalence trend fitting and incidence estimation in EPP 2013

PubMed Central

Brown, Tim; Bao, Le; Eaton, Jeffrey W.; Hogan, Daniel R.; Mahy, Mary; Marsh, Kimberly; Mathers, Bradley M.; Puckett, Robert

2014-01-01

Objective: Describe modifications to the latest version of the Joint United Nations Programme on AIDS (UNAIDS) Estimation and Projection Package component of Spectrum (EPP 2013) to improve prevalence fitting and incidence trend estimation in national epidemics and global estimates of HIV burden. Methods: Key changes made under the guidance of the UNAIDS Reference Group on Estimates, Modelling and Projections include: availability of a range of incidence calculation models and guidance for selecting a model; a shift to reporting the Bayesian median instead of the maximum likelihood estimate; procedures for comparison and validation against reported HIV and AIDS data; incorporation of national surveys as an integral part of the fitting and calibration procedure, allowing survey trends to inform the fit; improved antenatal clinic calibration procedures in countries without surveys; adjustment of national antiretroviral therapy reports used in the fitting to include only those aged 15–49 years; better estimates of mortality among people who inject drugs; and enhancements to speed fitting. Results: The revised models in EPP 2013 allow closer fits to observed prevalence trend data and reflect improving understanding of HIV epidemics and associated data. Conclusion: Spectrum and EPP continue to adapt to make better use of the existing data sources, incorporate new sources of information in their fitting and validation procedures, and correct for quantifiable biases in inputs as they are identified and understood. These adaptations provide countries with better calibrated estimates of incidence and prevalence, which increase epidemic understanding and provide a solid base for program and policy planning. PMID:25406747

Prevalence of the Metabolic Syndrome among Korean Workers by Occupational Group: Fifth Korean National Health and Nutrition Examination Survey (KNHANES) 2010

PubMed Central

2013-01-01

Objectives The prevalence of the metabolic syndrome has increased rapidly in South Korea over the past 10 years. However, the occurrence of the metabolic syndrome in workers grouped according to the specific type of work is not well understood in Korea. In this study, we assessed the differences in the prevalence of the metabolic syndrome by occupational group and evaluated the risk of the metabolic syndrome among occupational groups. Methods From the Fifth Korean National Health and Nutrition Examination Survey (2010), 3,303 employed participants were included in this study. The unadjusted and age-adjusted prevalences of the metabolic syndrome were estimated and multiple logistic regression analysis was conducted using the presence of the metabolic syndrome as a dependent variable, and adjusting for age, education level, household income, drinking behavior, smoking status, physical activity, work hours, and work scheduling pattern. Results Among male workers, non-manual workers had the greatest age-adjusted prevalence (26.4%, 95% CI: 22.3-30.5%) among the occupational groups. In a logistic regression analysis, male manual workers had a significantly lower odds ratio for the metabolic syndrome relative to non-manual workers (0.59, 95% CI: 0.41-0.85). Conclusion Our study demonstrated differences in the prevalence of the metabolic syndrome by occupational group and identified the greatest risk for the metabolic syndrome in male non-manual workers. PMID:24472422

Standards for reporting chronic periodontitis prevalence and severity in epidemiologic studies: Proposed standards from the Joint EU/USA Periodontal Epidemiology Working Group.

PubMed

Holtfreter, Birte; Albandar, Jasim M; Dietrich, Thomas; Dye, Bruce A; Eaton, Kenneth A; Eke, Paul I; Papapanou, Panos N; Kocher, Thomas

2015-05-01

Periodontal diseases are common and their prevalence varies in different populations. However, prevalence estimates are influenced by the methodology used, including measurement techniques, case definitions, and periodontal examination protocols, as well as differences in oral health status. As a consequence, comparisons between populations are severely hampered and inferences regarding the global variation in prevalence can hardly be drawn. To overcome these limitations, the authors suggest standardized principles for the reporting of the prevalence and severity of periodontal diseases in future epidemiological studies. These principles include the comprehensive reporting of the study design, the recording protocol, and specific subject-related and oral data. Further, a range of periodontal data should be reported in the total population and within specific age groups. Periodontal data include the prevalence and extent of clinical attachment loss (CAL) and probing depth (PD) on site and tooth level according to specific thresholds, mean CAL/PD, the CDC/AAP case definition, and bleeding on probing. Consistent implementation of these standards in future studies will ensure improved reporting quality, permit meaningful comparisons of the prevalence of periodontal diseases across populations, and provide better insights into the determinants of such variation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Constraints to estimating the prevalence of trypanosome infections in East African zebu cattle.

PubMed

Cox, Andrew P; Tosas, Olga; Tilley, Aimee; Picozzi, Kim; Coleman, Paul; Hide, Geoff; Welburn, Susan C

2010-09-06

In East Africa, animal trypanosomiasis is caused by many tsetse transmitted protozoan parasites including Trypanosoma vivax, T. congolense and subspecies of T. brucei s.l. (T. b. brucei and zoonotic human infective T. b. rhodesiense) that may co-circulate in domestic and wild animals. Accurate species-specific prevalence measurements of these parasites in animal populations are complicated by mixed infections of trypanosomes within individual hosts, low parasite densities and difficulties in conducting field studies. Many Polymerase Chain Reaction (PCR) based diagnostic tools are available to characterise and quantify infection in animals. These are important for assessing the contribution of infections in animal reservoirs and the risk posed to humans from zoonotic trypanosome species. New matrices for DNA capture have simplified large scale field PCR analyses but few studies have examined the impact of these techniques on prevalence estimations. The Whatman FTA matrix has been evaluated using a random sample of 35 village zebu cattle from a population naturally exposed to trypanosome infection. Using a generic trypanosome-specific PCR, prevalence was systematically evaluated. Multiple PCR samples taken from single FTA cards demonstrated that a single punch from an FTA card is not sufficient to confirm the infectivity status of an individual animal as parasite DNA is unevenly distributed across the card. At low parasite densities in the host, this stochastic sampling effect results in underestimation of prevalence based on single punch PCR testing. Repeated testing increased the estimated prevalence of all Trypanosoma spp. from 9.7% to 86%. Using repeat testing, a very high prevalence of pathogenic trypanosomes was detected in these local village cattle: T. brucei (34.3%), T. congolense (42.9%) and T. vivax (22.9%). These results show that, despite the convenience of Whatman FTA cards and specific PCR based detection tools, the chronically low parasitaemias in

Estimating HIV Prevalence in Zimbabwe Using Population-Based Survey Data

PubMed Central

Chinomona, Amos; Mwambi, Henry Godwell

2015-01-01

Estimates of HIV prevalence computed using data obtained from sampling a subgroup of the national population may lack the representativeness of all the relevant domains of the population. These estimates are often computed on the assumption that HIV prevalence is uniform across all domains of the population. Use of appropriate statistical methods together with population-based survey data can enhance better estimation of national and subgroup level HIV prevalence and can provide improved explanations of the variation in HIV prevalence across different domains of the population. In this study we computed design-consistent estimates of HIV prevalence, and their respective 95% confidence intervals at both the national and subgroup levels. In addition, we provided a multivariable survey logistic regression model from a generalized linear modelling perspective for explaining the variation in HIV prevalence using demographic, socio-economic, socio-cultural and behavioural factors. Essentially, this study borrows from the proximate determinants conceptual framework which provides guiding principles upon which socio-economic and socio-cultural variables affect HIV prevalence through biological behavioural factors. We utilize the 2010–11 Zimbabwe Demographic and Health Survey (2010–11 ZDHS) data (which are population based) to estimate HIV prevalence in different categories of the population and for constructing the logistic regression model. It was established that HIV prevalence varies greatly with age, gender, marital status, place of residence, literacy level, belief on whether condom use can reduce the risk of contracting HIV and level of recent sexual activity whereas there was no marked variation in HIV prevalence with social status (measured using a wealth index), method of contraceptive and an individual’s level of education. PMID:26624280

Estimating micro area behavioural risk factor prevalence from large population-based surveys: a full Bayesian approach.

PubMed

Seliske, L; Norwood, T A; McLaughlin, J R; Wang, S; Palleschi, C; Holowaty, E

2016-06-07

An important public health goal is to decrease the prevalence of key behavioural risk factors, such as tobacco use and obesity. Survey information is often available at the regional level, but heterogeneity within large geographic regions cannot be assessed. Advanced spatial analysis techniques are demonstrated to produce sensible micro area estimates of behavioural risk factors that enable identification of areas with high prevalence. A spatial Bayesian hierarchical model was used to estimate the micro area prevalence of current smoking and excess bodyweight for the Erie-St. Clair region in southwestern Ontario. Estimates were mapped for male and female respondents of five cycles of the Canadian Community Health Survey (CCHS). The micro areas were 2006 Census Dissemination Areas, with an average population of 400-700 people. Two individual-level models were specified: one controlled for survey cycle and age group (model 1), and one controlled for survey cycle, age group and micro area median household income (model 2). Post-stratification was used to derive micro area behavioural risk factor estimates weighted to the population structure. SaTScan analyses were conducted on the granular, postal-code level CCHS data to corroborate findings of elevated prevalence. Current smoking was elevated in two urban areas for both sexes (Sarnia and Windsor), and an additional small community (Chatham) for males only. Areas of excess bodyweight were prevalent in an urban core (Windsor) among males, but not females. Precision of the posterior post-stratified current smoking estimates was improved in model 2, as indicated by narrower credible intervals and a lower coefficient of variation. For excess bodyweight, both models had similar precision. Aggregation of the micro area estimates to CCHS design-based estimates validated the findings. This is among the first studies to apply a full Bayesian model to complex sample survey data to identify micro areas with variation in risk

[Asthma prevalence estimated using a standard algorithm based on electronic health data in various areas of Italy].

PubMed

Tessari, Roberta; Migliore, Enrica; Balzi, Daniela; Barchielli, Alessandro; Canova, Cristina; Faustini, Annunziata; Galassi, Claudia; Simonato, Lorenzo

2008-01-01

development of an algorithm to estimate asthma prevalence by record linkage of different health databases: causes of death (CM), hospital discharges (SDO), drug prescriptions archive (PF), health tax exemptions (ET) in three Italian areas. Venezia AULSS 12, city of Torino, Firenze ASL 10. residents aged between 0 and 34 years in the above three centres in the three year period 2002-2004, for a total of 661,275 inhabitants on 30 June 2003. annual crude and standardized prevalence (per 100 inhabitants) with 95% confidence intervals by gender and age groups (0-14, 15-34, total: 0-34 years). for each year of interest, we selected the following: cases with asthma as primary cause of death from CM; all persons discharged from hospitals with diagnosis (primary or secondary) of asthma (ICD9-CM code = 493*); selected prescriptions of anti-asthma drugs (ATC code = R03A, R03CC02, R03CC04, R03CK, R03DC01, R03DC03), and health-tax exemptions for asthma (code = 007.493) from ET. We defined as prevalent case a subject who was present every single year in at least one of four health databases. We reported the absolute and relative contribution of each information system by area, age, gender and year of interest. A sensitivity analysis using more restrictive criteria to identify prevalent cases (two or more prescriptions per year) was also performed. the PF archive is the most important information source in identifying prevalent cases (from 92.5% of Torino to 95.4% of Firenze). The standardized prevalence of asthma in 0-34 years of age is higher in Venezia (6.37%; 2003 year) than in the other two areas, which show similar values (4.01% in Firenze, 3.77% in Torino; 2003 year). In both genders, the standardized prevalence of asthma is, for all centers, clearly higher in the 0-14 age group than in the 15-34 age group. However, Venezia has a prevalence almost twice (11.21%) that of Firenze (6.20%) and Torino (5.60%) in the 0-14years age group. The use of more restrictive criteria in

Estimated hepatitis C prevalence and key population sizes in San Francisco: A foundation for elimination.

PubMed

Facente, Shelley N; Grebe, Eduard; Burk, Katie; Morris, Meghan D; Murphy, Edward L; Mirzazadeh, Ali; Smith, Aaron A; Sanchez, Melissa A; Evans, Jennifer L; Nishimura, Amy; Raymond, Henry F

2018-01-01

Initiated in 2016, End Hep C SF is a comprehensive initiative to eliminate hepatitis C (HCV) infection in San Francisco. The introduction of direct-acting antivirals to treat and cure HCV provides an opportunity for elimination. To properly measure progress, an estimate of baseline HCV prevalence, and of the number of people in various subpopulations with active HCV infection, is required to target and measure the impact of interventions. Our analysis was designed to incorporate multiple relevant data sources and estimate HCV burden for the San Francisco population as a whole, including specific key populations at higher risk of infection. Our estimates are based on triangulation of data found in case registries, medical records, observational studies, and published literature from 2010 through 2017. We examined subpopulations based on sex, age and/or HCV risk group. When multiple sources of data were available for subpopulation estimates, we calculated a weighted average using inverse variance weighting. Credible ranges (CRs) were derived from 95% confidence intervals of population size and prevalence estimates. We estimate that 21,758 residents of San Francisco are HCV seropositive (CR: 10,274-42,067), representing an overall seroprevalence of 2.5% (CR: 1.2%- 4.9%). Of these, 16,408 are estimated to be viremic (CR: 6,505-37,407), though this estimate includes treated cases; up to 12,257 of these (CR: 2,354-33,256) are people who are untreated and infectious. People who injected drugs in the last year represent 67.9% of viremic HCV infections. We estimated approximately 7,400 (51%) more HCV seropositive cases than are included in San Francisco's HCV surveillance case registry. Our estimate provides a useful baseline against which the impact of End Hep C SF can be measured.

Combination of five diagnostic tests to estimate the prevalence of hookworm infection among school-aged children from a rural area of colombia.

PubMed

Barreto, Rafael E; Narváez, Javier; Sepúlveda, Natalia A; Velásquez, Fabián C; Díaz, Sandra C; López, Myriam Consuelo; Reyes, Patricia; Moncada, Ligia I

2017-09-01

Public health programs for the control of soil-transmitted helminthiases require valid diagnostic tests for surveillance and parasitic control evaluation. However, there is currently no agreement about what test should be used as a gold standard for the diagnosis of hookworm infection. Still, in presence of concurrent data for multiple tests it is possible to use statistical models to estimate measures of test performance and prevalence. The aim of this study was to estimate the diagnostic accuracy of five parallel tests (direct microscopic examination, Kato-Katz, Harada-Mori, modified Ritchie-Frick, and culture in agar plate) to detect hookworm infections in a sample of school-aged children from a rural area in Colombia. We used both, a frequentist approach, and Bayesian latent class models to estimate the sensitivity and specificity of five tests for hookworm detection, and to estimate the prevalence of hookworm infection in absence of a Gold Standard. The Kato-Katz and agar plate methods had an overall agreement of 95% and kappa coefficient of 0.76. Different models estimated a sensitivity between 76% and 92% for the agar plate technique, and 52% to 87% for the Kato-Katz technique. The other tests had lower sensitivity. All tests had specificity between 95% and 98%. The prevalence estimated by the Kato-Katz and Agar plate methods for different subpopulations varied between 10% and 14%, and was consistent with the prevalence estimated from the combination of all tests. The Harada-Mori, Ritchie-Frick and direct examination techniques resulted in lower and disparate prevalence estimates. Bayesian approaches assuming imperfect specificity resulted in lower prevalence estimates than the frequentist approach. Copyright © 2017 Elsevier B.V. All rights reserved.

Comfort in big numbers: Does over-estimation of doping prevalence in others indicate self-involvement?

PubMed Central

Petróczi, Andrea; Mazanov, Jason; Nepusz, Tamás; Backhouse, Susan H; Naughton, Declan P

2008-01-01

Background The 'False Consensus Effect' (FCE), by which people perceive their own actions as relatively common behaviour, might be exploited to gauge whether a person engages in controversial behaviour, such as performance enhancing drug (PED) use. Hypothesis It is assumed that people's own behaviour, owing to the FCE, affects their estimation of the prevalence of that behaviour. It is further hypothesised that a person's estimate of PED population use is a reliable indicator of the doping behaviour of that person, in lieu of self-reports. Testing the hypothesis Over- or underestimation is calculated from investigating known groups (i.e. users vs. non-users), using a short questionnaire, and a known prevalence rate from official reports or sample evidence. It is proposed that sample evidence from self-reported behaviour should be verified using objective biochemical analyses. In order to find proofs of concept for the existence of false consensus, a pilot study was conducted. Data were collected among competitive UK student-athletes (n = 124) using a web-based anonymous questionnaire. User (n = 9) vs. non-user (n = 76) groups were established using self-reported information on doping use and intention to use PEDs in hypothetical situations. Observed differences in the mean estimation of doping made by the user group exceeded the estimation made by the non-user group (35.11% vs. 15.34% for general doping and 34.25% vs. 26.30% in hypothetical situations, respectively), thus providing preliminary evidence in support of the FCE concept in relation to doping. Implications of the hypothesis The presence of the FCE in estimating doping prevalence or behaviour in others suggests that the FCE based approach may be an avenue for developing an indirect self-report mechanism for PED use behaviour. The method may be successfully adapted to the estimation of prevalence of behaviours where direct self-reports are assumed to be distorted by socially desirable responding. Thus this

Constraints to estimating the prevalence of trypanosome infections in East African zebu cattle

PubMed Central

2010-01-01

Background In East Africa, animal trypanosomiasis is caused by many tsetse transmitted protozoan parasites including Trypanosoma vivax, T. congolense and subspecies of T. brucei s.l. (T. b. brucei and zoonotic human infective T. b. rhodesiense) that may co-circulate in domestic and wild animals. Accurate species-specific prevalence measurements of these parasites in animal populations are complicated by mixed infections of trypanosomes within individual hosts, low parasite densities and difficulties in conducting field studies. Many Polymerase Chain Reaction (PCR) based diagnostic tools are available to characterise and quantify infection in animals. These are important for assessing the contribution of infections in animal reservoirs and the risk posed to humans from zoonotic trypanosome species. New matrices for DNA capture have simplified large scale field PCR analyses but few studies have examined the impact of these techniques on prevalence estimations. Results The Whatman FTA matrix has been evaluated using a random sample of 35 village zebu cattle from a population naturally exposed to trypanosome infection. Using a generic trypanosome-specific PCR, prevalence was systematically evaluated. Multiple PCR samples taken from single FTA cards demonstrated that a single punch from an FTA card is not sufficient to confirm the infectivity status of an individual animal as parasite DNA is unevenly distributed across the card. At low parasite densities in the host, this stochastic sampling effect results in underestimation of prevalence based on single punch PCR testing. Repeated testing increased the estimated prevalence of all Trypanosoma spp. from 9.7% to 86%. Using repeat testing, a very high prevalence of pathogenic trypanosomes was detected in these local village cattle: T. brucei (34.3%), T. congolense (42.9%) and T. vivax (22.9%). Conclusions These results show that, despite the convenience of Whatman FTA cards and specific PCR based detection tools, the

Calculation of prevalence estimates through differential equations: application to stroke-related disability.

PubMed

Mar, Javier; Sainz-Ezkerra, María; Moler-Cuiral, Jose Antonio

2008-01-01

Neurological diseases now make up 6.3% of the global burden of disease mainly because they cause disability. To assess disability, prevalence estimates are needed. The objective of this study is to apply a method based on differential equations to calculate the prevalence of stroke-related disability. On the basis of a flow diagram, a set of differential equations for each age group was constructed. The linear system was solved analytically and numerically. The parameters of the system were obtained from the literature. The model was validated and calibrated by comparison with previous results. The stroke prevalence rate per 100,000 men was 828, and the rate for stroke-related disability was 331. The rates steadily rose with age, but the group between the ages of 65 and 74 years had the highest total number of individuals. Differential equations are useful to represent the natural history of neurological diseases and to make possible the calculation of the prevalence for the various states of disability. In our experience, when compared with the results obtained by Markov models, the benefit of the continuous use of time outweighs the mathematical requirements of our model. (c) 2008 S. Karger AG, Basel.

Prevalence of hepatitis B virus infection among Iranian high risk groups: a systematic review and meta-analysis

PubMed Central

Almasi-Hashiani, Amir; Ayubi, Erfan; Mansori, Kamyar; Salehi-Vaziri, Mostafa; Moradi, Yousef; Gholamaliei, Behzad; Khazaei, Salman

2018-01-01

Aim: Present study aimed to systematically review and quantitatively synthesize published data about the prevalence of Hepatitis B Virus (HBV) infection among high risk groups in Iran. Background: Determining true burden of Hepatitis B Virus (HBV) infection among high-risk groups relies on knowledge of occurrence measures such as prevalence rate. There is no conclusive and comprehensive data regarding to prevalence of HBV infection among high risk groups in Iran. Methods: Relevant studies were searched in PubMed, Scopus, Web of Knowledge and local databases. In addition, reference lists of relevant studies were searched manually. Two independent authors reviewed the eligibility of retrieved studies and extracted the required data. Studies reporting HBV infection among high risk groups were included in the meta-analysis using random effects models. Meta regression and sub-group analysis were considered as additional analyses. Results: The initial search yielded 566 citations. After the primary screen, 37 studies were selected for review. Meta-analysis results showed that pooled prevalence of HBV infection among high risk groups in Iran was 4.8% (95% confidence interval: 3.6%-6.1%), with the highest prevalence among in prisoners (5%; 3%-6%), and in central regions of Iran (7%; 4%-11%). Year of study may affect the observed heterogeneity in the estimated prevalence of HBV infection among injection drug users (IDUs) and prisoners. Conclusion: Our results indicate that prevalence of HBV infection among high risk groups was seemingly high in Iran. Health policy decision makers should be aware of prevalence of HBV infection among different high risk groups and in different regions of Iran.

[Chronic obstructive pulmonary disease prevalence estimated using a standard algorithm based on electronic health data in various areas of Italy].

PubMed

Faustini, Annunziata; Cascini, Silvia; Arcà, Massimo; Balzi, Daniela; Barchielli, Alessandro; Canova, Cristina; Galassi, Claudia; Migliore, Enrica; Minerba, Sante; Protti, Maria Angela; Romanelli, Anna; Tessari, Roberta; Vigotti, Maria Angela; Simonato, Lorenzo

2008-01-01

to estimate the prevalence of chronic obstructive pulmonary disease (COPD) by integrating various administrative health information systems. prevalent COPD cases were defined as those reported in the hospital discharge registry (HDR) and cause of mortality registry (CMR) with codes 490*, 491*, 492*, 494* and 496* of the International diseases classification 9th revision. Annual prevalence was estimated in 35+ year-old residents in six Italian areas ofb different sizes, in the period 2002-2004. We included cases observed in the previous four years who were alive at the beginning of each year. in 2003, age-standardized prevalence rates varied from 1.6% in Venice to 5% in Taranto. Prevalence was higher in males and increased with age. The highest rates were observed in central (Rome) and southern (Taranto) cities, especially in the 35-64 age group. HDR contributed 91% of cases. Health-tax exemption registry would increase the prevalence estimate by 0.2% if used as a third data source. with respect to the National Health Status survey, COPD prevalence is underestimated by 1%-3%; this can partly be due to the selection of severe and exacerbated COPD by the algorithm used. However, age, gender and geographical characteristics of prevalent cases were comparable to national estimates. Including cases observed in previous years (longitudinal estimates) increased the point estimate (yearly) of prevalence two or three times in each area.

The prevalence of specific dental anomalies in a group of Saudi cleft lip and palate patients.

PubMed

Al-Kharboush, Ghada H; Al-Balkhi, Khalid M; Al-Moammar, Khalid

2015-04-01

The aims of this study were to investigate the prevalence and distribution of dental anomalies in a group of Saudi subjects with cleft lip and palate (CLP), to examine potential sex-based associations of these anomalies, and to compare dental anomalies in Saudi subjects with CLP with published data from other population groups. This retrospective study involved the examination of pre-treatment records obtained from three CLP centers in Riyadh, Saudi Arabia, in February and March 2010. The pre-treatment records of 184 subjects with cleft lip and palate were identified and included in this study. Pre-treatment maxillary occlusal radiographs of the cleft region, panoramic radiographs, and orthodontic study models of subjects with CLP were analyzed for dental anomalies. Orthopantomographs and occlusal radiographs may not be reliable for the accurate evaluation of root malformation anomalies. A total of 265 dental anomalies were observed in the 184 study subjects. Hypodontia was observed most commonly (66.8%), followed by microdontia (45.6%), intra-oral ectopic eruption (12.5%), supernumerary teeth (12.5%), intra-nasal ectopic eruption (3.2), and macrodontia (3.2%). No gender difference in the prevalence of these anomalies was observed. Dental anomalies were common in Saudi subjects with CLP type. This will complicate the health care required for the CL/P subjects. This study was conducted to epidemiologically explore the prevalence of dental anomalies among Saudi Arabian subjects with CLP.

Estimated prevalence of dementia based on analysis of drug databases in the Region of Madrid (Spain).

PubMed

de Hoyos-Alonso, M C; Bonis, J; Tapias-Merino, E; Castell, M V; Otero, A

2016-01-01

The progressive rise in dementia prevalence increases the need for rapid methods that complement population-based prevalence studies. To estimate the prevalence of dementia in the population aged 65 and older based on use of cholinesterase inhibitors and memantine. Descriptive study of use and prescription of cholinesterase inhibitors and/or memantine in 2011 according to 2 databases: Farm@drid (pharmacy billing records for the Region of Madrid) and BIFAP (database for pharmacoepidemiology research in primary care, with diagnosis and prescription records). We tested the comparability of drug use results from each database using the chi-square test and prevalence ratios. The prevalence of dementia in Madrid was estimated based on the dose per 100 inhabitants/day, adjusting the result for data obtained from BIFAP on combination treatment in the general population (0.37%) and the percentage of dementia patients undergoing treatment (41.13%). Cholinesterase inhibitors and memantine were taken by 2.08% and 0.72% of Madrid residents aged 65 and older was respectively. Both databases displayed similar results for use of these drugs. The estimated prevalence of dementia in individuals aged 65 and older is 5.91% (95% CI%, 5.85-5.95) (52 287 people), and it is higher in women (7.16%) than in men (4.00%). The estimated prevalence of dementia is similar to that found in population-based studies. Analysing consumption of specific dementia drugs can be a reliable and inexpensive means of updating prevalence data periodically and helping rationalise healthcare resources. Copyright © 2014 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

The Prevalence of Multiple Sclerosis in the Metropolitan Area of Rome: A Capture-Recapture Analysis.

PubMed

Farcomeni, Alessio; Cortese, Antonio; Sgarlata, Eleonora; Alunni Fegatelli, Danilo; Marfia, Gerolama Alessandra; Buttari, Fabio; Mirabella, Massimiliano; De Fino, Chiara; Prosperini, Luca; Pozzilli, Carlo; Grasso, Maria Grazia; Iasevoli, Luigi; Di Battista, Giancarlo; Millefiorini, Enrico

2018-03-02

Limited data are available on the prevalence of multiple sclerosis (MS) in central Italy. The objective of this study is to estimate MS prevalence in the metropolitan area of Rome. We used the capture-recapture method to calculate prevalence estimates in the study area. The selected prevalence day was December 31, 2015. A total of 1,007 patients, with a definite diagnosis of MS according to the revised McDonald's criteria, were considered for crude, age- and sex-specific prevalence estimation. The overall crude prevalence rate was 146.2 cases per 100,000 (95% CI 119.9-172.5). A higher prevalence rate was recorded in females (194.1, 95% CI 149.6-238.6) than in males (93.0, 95% CI 67.2-118.8) with a female to male ratio of 1.8. Age-specific prevalence peaked in the 25-34 , 35-44 and 45-54 years class; moreover, it was found to increase up to the 45-54 years age group in females and the 35-44 years age group in males, decreasing thereafter. The results confirm that the metropolitan area of Rome is a high-risk area for MS. © 2018 S. Karger AG, Basel.

Prevalence of Group C Streptococcus and Fusobacterium Necrophorum in Patients With Sore Throat: A Meta-Analysis.

PubMed

Marchello, Christian; Ebell, Mark H

2016-11-01

The prevalence of Group C beta-hemolytic streptococcus and Fusobacterium necrophorum among patients with sore throat in the outpatient setting has not been previously summarized. We set out to derive prevalence information from the existing literature. We performed a systematic review of MEDLINE for studies reporting the prevalence of F necrophorum or Group C streptococcus or both in prospective, consecutive series of outpatients with sore throat, as well as laboratory-based studies of throat cultures submitted from primary care. We limited searches to studies where the majority of data was collected after January 1, 2000, to reflect contemporary microbiological methods and prevalences. Each author independently reviewed the articles for inclusion and abstraction of data; we resolved discrepancies by consensus discussion. We then performed a meta-analysis to calculate the pooled prevalence estimates using a random effects model of raw proportions. A total of 16 studies met our inclusion criteria. The overall prevalences of Group C streptococcus and F necrophorum were 6.1% (95% CI, 3.2%-9.0%) and 18.9% (95% CI, 10.5%-27.2%), respectively. When stratified by study type, the prevalences of Group C streptococcus and F necrophorum in laboratory-based studies were 6.6% (95% CI, -1.0% to 14.2%) and 18.8% (95% CI, 6.5%-31.1%), respectively. In primary care patients with sore throat, Group C streptococcus had a prevalence of 6.1% (95% CI, 3.1%-9.2%), while F necrophorum had a prevalence of 19.4% (95% CI, 14.7%-24.1%). Group C streptococcus and Fusobacterium necrophorum are commonly detected in patients with acute pharyngitis. Research is needed, however, to determine whether these bacteria are truly pathogenic in patients with pharyngitis and whether antibiotics reduce the duration of symptoms or the likelihood of complications. © 2016 Annals of Family Medicine, Inc.

Validation of Diagnostic Groups Based on Health Care Utilization Data Should Adjust for Sampling Strategy.

PubMed

Cadieux, Geneviève; Tamblyn, Robyn; Buckeridge, David L; Dendukuri, Nandini

2017-08-01

Valid measurement of outcomes such as disease prevalence using health care utilization data is fundamental to the implementation of a "learning health system." Definitions of such outcomes can be complex, based on multiple diagnostic codes. The literature on validating such data demonstrates a lack of awareness of the need for a stratified sampling design and corresponding statistical methods. We propose a method for validating the measurement of diagnostic groups that have: (1) different prevalences of diagnostic codes within the group; and (2) low prevalence. We describe an estimation method whereby: (1) low-prevalence diagnostic codes are oversampled, and the positive predictive value (PPV) of the diagnostic group is estimated as a weighted average of the PPV of each diagnostic code; and (2) claims that fall within a low-prevalence diagnostic group are oversampled relative to claims that are not, and bias-adjusted estimators of sensitivity and specificity are generated. We illustrate our proposed method using an example from population health surveillance in which diagnostic groups are applied to physician claims to identify cases of acute respiratory illness. Failure to account for the prevalence of each diagnostic code within a diagnostic group leads to the underestimation of the PPV, because low-prevalence diagnostic codes are more likely to be false positives. Failure to adjust for oversampling of claims that fall within the low-prevalence diagnostic group relative to those that do not leads to the overestimation of sensitivity and underestimation of specificity.

Estimating phylogenetic relationships despite discordant gene trees across loci: the species tree of a diverse species group of feather mites (Acari: Proctophyllodidae).

PubMed

Knowles, Lacey L; Klimov, Pavel B

2011-11-01

With the increased availability of multilocus sequence data, the lack of concordance of gene trees estimated for independent loci has focused attention on both the biological processes producing the discord and the methodologies used to estimate phylogenetic relationships. What has emerged is a suite of new analytical tools for phylogenetic inference--species tree approaches. In contrast to traditional phylogenetic methods that are stymied by the idiosyncrasies of gene trees, approaches for estimating species trees explicitly take into account the cause of discord among loci and, in the process, provides a direct estimate of phylogenetic history (i.e. the history of species divergence, not divergence of specific loci). We illustrate the utility of species tree estimates with an analysis of a diverse group of feather mites, the pinnatus species group (genus Proctophyllodes). Discord among four sequenced nuclear loci is consistent with theoretical expectations, given the short time separating speciation events (as evident by short internodes relative to terminal branch lengths in the trees). Nevertheless, many of the relationships are well resolved in a Bayesian estimate of the species tree; the analysis also highlights ambiguous aspects of the phylogeny that require additional loci. The broad utility of species tree approaches is discussed, and specifically, their application to groups with high speciation rates--a history of diversification with particular prevalence in host/parasite systems where species interactions can drive rapid diversification.

Geostatistical Model-Based Estimates of Schistosomiasis Prevalence among Individuals Aged ≤20 Years in West Africa

PubMed Central

Schur, Nadine; Hürlimann, Eveline; Garba, Amadou; Traoré, Mamadou S.; Ndir, Omar; Ratard, Raoult C.; Tchuem Tchuenté, Louis-Albert; Kristensen, Thomas K.; Utzinger, Jürg; Vounatsou, Penelope

2011-01-01

Background Schistosomiasis is a water-based disease that is believed to affect over 200 million people with an estimated 97% of the infections concentrated in Africa. However, these statistics are largely based on population re-adjusted data originally published by Utroska and colleagues more than 20 years ago. Hence, these estimates are outdated due to large-scale preventive chemotherapy programs, improved sanitation, water resources development and management, among other reasons. For planning, coordination, and evaluation of control activities, it is essential to possess reliable schistosomiasis prevalence maps. Methodology We analyzed survey data compiled on a newly established open-access global neglected tropical diseases database (i) to create smooth empirical prevalence maps for Schistosoma mansoni and S. haematobium for individuals aged ≤20 years in West Africa, including Cameroon, and (ii) to derive country-specific prevalence estimates. We used Bayesian geostatistical models based on environmental predictors to take into account potential clustering due to common spatially structured exposures. Prediction at unobserved locations was facilitated by joint kriging. Principal Findings Our models revealed that 50.8 million individuals aged ≤20 years in West Africa are infected with either S. mansoni, or S. haematobium, or both species concurrently. The country prevalence estimates ranged between 0.5% (The Gambia) and 37.1% (Liberia) for S. mansoni, and between 17.6% (The Gambia) and 51.6% (Sierra Leone) for S. haematobium. We observed that the combined prevalence for both schistosome species is two-fold lower in Gambia than previously reported, while we found an almost two-fold higher estimate for Liberia (58.3%) than reported before (30.0%). Our predictions are likely to overestimate overall country prevalence, since modeling was based on children and adolescents up to the age of 20 years who are at highest risk of infection. Conclusion/Significance We

Integrating environmental and self-report data to refine cannabis prevalence estimates in a major urban area of Switzerland.

PubMed

Been, Frederic; Schneider, Christian; Zobel, Frank; Delémont, Olivier; Esseiva, Pierre

2016-10-01

Cannabis consumption is a topical subject because of discussions about reviewing current regulations. In this context, having a more comprehensive approach to assess and monitor prevalence and consumption is highly relevant. The objective of this work was to refine current estimates about prevalence of cannabis use by combining self-report data and results derived from wastewater analysis. Self-report data was retrieved from surveys conducted in Switzerland and Europe. Wastewater samples were collected at the wastewater treatment plant of Lausanne, western Switzerland, over a 15 months period. The occurrence of 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH), a specific metabolite of delta-9-tetrahydrocannabinol (THC), was monitored. Bayesian hierarchical models were used to estimate consumption, prevalence and number of cannabis users in the investigated area. According to survey data, 12-months prevalence in western Switzerland was estimated to 6.2% of the population aged 15 or older, with an estimated daily cannabis consumption of 8.1gday(-1)·1000inhab(-1) (at 11.2% purity). The integrative model comprising self-report and wastewater data substantially reduced the uncertainty in the estimates and suggested a last-year prevalence of 9.4%, with a daily cannabis consumption of 14.0gday(-1)·1000inhab(-1). Although in the same order of magnitude, consumption and prevalence estimates obtained with the integrative model were 78% and 52% higher compared to self-report figures, respectively. Interestingly, these figures are similar to discrepancies observed when comparing self-reported alcohol consumption and sales or tax data. The suggested integrative model allowed to account for known sources of uncertainty and provided refined estimates of cannabis prevalence in a major urban area of Switzerland. Copyright © 2016 Elsevier B.V. All rights reserved.

The prevalence of disability among children: paradigms and estimates.

PubMed

Mudrick, Nancy R

2002-11-01

Every examination of disability among children must first grapple with definition of disability. The challenges to identifying disability among children involve not only determining the appropriate paradigm for defining disability, but also applying that paradigm to children in a meaningful way. This discussion of the prevalence of disability among children starts by examining the various paradigms utilized to identify disability and how they are interpreted when applied to children. Estimates of the prevalence of childhood disability, under different definitions of disability are presented. The goal of the discussion is to illustrate the sensitivity of the estimates of disability prevalence to the particular definition and data set used. Finally, the potential influence of the choice of paradigm on further measurement and service delivery is outlined.

Joint use of epidemiological and hospital medico-administrative data to estimate prevalence. Application to French data on breast cancer.

PubMed

Colonna, Marc; Mitton, Nicolas; Schott, Anne-Marie; Remontet, Laurent; Olive, Frédéric; Gomez, Frédéric; Iwaz, Jean; Polazzi, Stéphanie; Bossard, Nadine; Trombert, Béatrice

2012-04-01

Estimate complete, limited-duration, and hospital prevalence of breast cancer in a French Département covered by a population-based cancer registry and in whole France using complementary information sources. Incidence data from a cancer registry, national incidence estimations for France, mortality data, and hospital medico-administrative data were used to estimate the three prevalence indices. The methods included a modelling of epidemiological data and a specific process of data extraction from medico-administrative databases. Limited-duration prevalence at 33 years was a proxy for complete prevalence only in patients aged less than 70 years. In 2007 and in women older than 15 years, the limited-duration prevalence at 33 years rate per 100,000 women was estimated at 2372 for Département Isère and 2354 for whole France. The latter rate corresponded to 613,000 women. The highest rate corresponded to women aged 65-74 years (6161 per 100,000 in whole France). About one third of the 33-year limited-duration prevalence cases were diagnosed five years before and about one fourth were hospitalized for breast-cancer-related care (i.e., hospital prevalence). In 2007, the rate of hospitalized women was 557 per 100,000 in whole France. Among the 120,310 women hospitalized for breast-cancer-related care in 2007, about 13% were diagnosed before 2004. Limited-duration prevalence (long- and short-term), and hospital prevalence are complementary indices of cancer prevalence. Their efficient direct or indirect estimations are essential to reflect the burden of the disease and forecast median- and long-term medical, economic, and social patient needs, especially after the initial treatment. Copyright © 2011 Elsevier Ltd. All rights reserved.

Missing the Mark? A Two Time Point Cohort Study Estimating Intestinal Parasite Prevalence in Informal Settlements in Lima, Peru.

PubMed

Cooper, Michael Townsend; Searing, Rapha A; Thompson, David M; Bard, David; Carabin, Hélène; Gonzales, Carlos; Zavala, Carmen; Woodson, Kyle; Naifeh, Monique

2017-01-01

Objectives: The World Health Organization's (WHO) recommendations list Peru as potentially needing prevention of soil-transmitted helminthiasis (STH). Prevalence of STH varies regionally and remains understudied in the newest informal settlements of the capital city, Lima. The purpose of this study was to evaluate the need for Mass Drug Administration (MDA) of antiparasitic drugs in the newest informal settlements of Lima. The aim of this study was to estimate the season-specific prevalence of STH to determine if these prevalence estimates met the WHO threshold for MDA in 3 informal settlements. Methods : A 2 time point cohort study was conducted among a sample of 140 children aged 1 to 10 years living in 3 purposively sampled informal settlements of Lima, Peru. Children were asked to provide 2 stool samples that were analyzed with the spontaneous sedimentation in tube technique. The season-specific prevalence proportions of MDA-targeted STH were estimated using a hidden (latent) Markov modeling approach to adjust for repeated measurements over the 2 seasons and the imperfect validity of the screening tests. Results : The prevalence of MDA targeted STH was low at 2.2% (95% confidence interval = 0.3% to 6%) and 3.8% (95% confidence interval = 0.7% to 9.3%) among children sampled in the summer and winter months, respectively, when using the most conservative estimate of test sensitivity. These estimates were below the WHO threshold for MDA (20%). Conclusions : Empiric treatment for STH by organizations active in the newest informal settlements is not supported by the data and could contribute to unnecessary medication exposures and poor allocation of resources.

Missing the Mark? A Two Time Point Cohort Study Estimating Intestinal Parasite Prevalence in Informal Settlements in Lima, Peru

PubMed Central

Cooper, Michael Townsend; Searing, Rapha A.; Thompson, David M.; Bard, David; Carabin, Hélène; Gonzales, Carlos; Zavala, Carmen; Woodson, Kyle; Naifeh, Monique

2017-01-01

Objectives: The World Health Organization’s (WHO) recommendations list Peru as potentially needing prevention of soil-transmitted helminthiasis (STH). Prevalence of STH varies regionally and remains understudied in the newest informal settlements of the capital city, Lima. The purpose of this study was to evaluate the need for Mass Drug Administration (MDA) of antiparasitic drugs in the newest informal settlements of Lima. The aim of this study was to estimate the season-specific prevalence of STH to determine if these prevalence estimates met the WHO threshold for MDA in 3 informal settlements. Methods: A 2 time point cohort study was conducted among a sample of 140 children aged 1 to 10 years living in 3 purposively sampled informal settlements of Lima, Peru. Children were asked to provide 2 stool samples that were analyzed with the spontaneous sedimentation in tube technique. The season-specific prevalence proportions of MDA-targeted STH were estimated using a hidden (latent) Markov modeling approach to adjust for repeated measurements over the 2 seasons and the imperfect validity of the screening tests. Results: The prevalence of MDA targeted STH was low at 2.2% (95% confidence interval = 0.3% to 6%) and 3.8% (95% confidence interval = 0.7% to 9.3%) among children sampled in the summer and winter months, respectively, when using the most conservative estimate of test sensitivity. These estimates were below the WHO threshold for MDA (20%). Conclusions: Empiric treatment for STH by organizations active in the newest informal settlements is not supported by the data and could contribute to unnecessary medication exposures and poor allocation of resources. PMID:29152541

Estimating age-specific reproductive numbers-A comparison of methods.

PubMed

Moser, Carlee B; White, Laura F

2016-01-01

Large outbreaks, such as those caused by influenza, put a strain on resources necessary for their control. In particular, children have been shown to play a key role in influenza transmission during recent outbreaks, and targeted interventions, such as school closures, could positively impact the course of emerging epidemics. As an outbreak is unfolding, it is important to be able to estimate reproductive numbers that incorporate this heterogeneity and to use surveillance data that is routinely collected to more effectively target interventions and obtain an accurate understanding of transmission dynamics. There are a growing number of methods that estimate age-group specific reproductive numbers with limited data that build on methods assuming a homogenously mixing population. In this article, we introduce a new approach that is flexible and improves on many aspects of existing methods. We apply this method to influenza data from two outbreaks, the 2009 H1N1 outbreaks in South Africa and Japan, to estimate age-group specific reproductive numbers and compare it to three other methods that also use existing data from social mixing surveys to quantify contact rates among different age groups. In this exercise, all estimates of the reproductive numbers for children exceeded the critical threshold of one and in most cases exceeded those of adults. We introduce a flexible new method to estimate reproductive numbers that describe heterogeneity in the population.

[Estimated prevalence of autism spectrum disorders in the Canary Islands].

PubMed

Fortea Sevilla, M S; Escandell Bermúdez, M O; Castro Sánchez, J J

2013-12-01

To make an initial estimate of the prevalence of autism spectrum disorders (ASDs) among children in the province of Las Palmas (Spain). Descriptive study was conducted on 1,796 children between the ages of 18 and 30 months of age, all part of the Child Health Surveillance of the Canary Islands, more specifically the province of Las Palmas, with a population of 1,090,605. The parents of children involved completed the Spanish version of the Modified Checklist for Autism in Toddlers (M-CHAT/ES) in the paediatric clinic. The positive cases were then diagnosed by experts by means of the Autism Diagnostic Interview-Revised (ADIR) and the Autism Diagnostic Observation Schedule (ADOS). A 0.61% prevalence of ASDs was determined, similar to that reported in previous studies using the same tools. The ratio was six girls for every five boys. This was contrary to the results of previous studies which suggested more boys than girls were affected. This may have been due to the sample size, which will have to be increased in future studies to confirm this outcome. An increased sample size and also spread to other age ranges should be used in order to obtain a more reliable estimate of prevalence. As regards the gender ratio, this could be a result of the small size of the sample researched, and should therefore be confirmed by further studies. Copyright © 2012 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Estimates of the population prevalence of injection drug users among hispanic residents of large US metropolitan areas.

PubMed

Pouget, Enrique R; Friedman, Samuel R; Cleland, Charles M; Tempalski, Barbara; Cooper, Hannah L F

2012-06-01

Little information exists on the population prevalence or geographic distribution of injection drug users (IDUs) who are Hispanic in the USA. Here, we present yearly estimates of IDU population prevalence among Hispanic residents of the 96 most populated US metropolitan statistical areas (MSAs) for 1992-2002. First, yearly estimates of the proportion of IDUs who were Hispanic in each MSA were created by combining data on (1) IDUs receiving drug treatment services in Substance Abuse and Mental Health Services Administration (SAMHSA)'s Treatment Entry Data System, (2) IDUs being tested in the Centers for Disease Control and Prevention (CDC) HIV-Counseling and Testing System, and (3) incident AIDS diagnoses among IDUs, supplemented by (4) data on IDUs who were living with AIDS. Then, the resulting proportions were multiplied by published yearly estimates of the number of IDUs of all racial/ethnic groups in each MSA to produce Hispanic IDU population estimates. These were divided by Hispanic population data to produce population prevalence rates. Time trends were tested using mixed-effects regression models. Hispanic IDU prevalence declined significantly on average (1992 mean = 192, median = 133; 2002 mean = 144, median = 93; units are per 10,000 Hispanics aged 15-64). The highest prevalence rates across time tended to be in smaller northeastern MSAs. Comparing the last three study years to the first three, prevalence decreased in 82% of MSAs and increased in 18%. Comparisons with data on drug-related mortality and hepatitis C mortality supported the validity of the estimates. Generally, estimates of Hispanic IDU population prevalence were higher than published estimates for non-Hispanic White residents and lower than published estimates for non-Hispanic Black residents. Further analysis indicated that the proportion of IDUs that was Hispanic decreased in 52% and increased in 48% of MSAs between 2002 and 2007. The estimates resulting from this study can

Anxiety and dysthymia: local prevalence estimates based on drug prescriptions by general practitioners in Turin (Italy).

PubMed

Mamo, C; Farina, E; Cicio, R; Fanì, M

2014-01-01

The aim of the study was to obtain local estimates of the prevalence of anxiety and dysthymic disorders among attendees of primary care at local level, useful to pursue a better management of the health care services. The study was conducted in the Health District no. 2 of Turin (industrial town in northwest Italy). The criteria for identification of cases were based on the drugs prescriptions made by general practitioners (GPs), selected in order to assure high specificity. The study involved 86 physicians (with 87,885 attendees). As expected, the crude and standardized prevalences were higher in women (anxiety: 2.9% vs 1.3% in men; dysthymia: 3.8% vs 1.7% in men), with a peak in women aged over 75 yrs (anxiety: 4.8%; dysthymia: 6.2%). In comparison to male GPs, female GPs had an higher prevalence of patients with anxious disorders, whereas the prevalences of dysthymia were similar. Despite the discussed limitations, the used methodology allows to obtain sufficiently reliable estimates of prevalence of common mental disorders at local level, providing informations useful for organizing the primary care in the Health district.

Clustered Regularly Interspaced Short Palindromic Repeats Are emm Type-Specific in Highly Prevalent Group A Streptococci.

PubMed

Zheng, Po-Xing; Chan, Yuen-Chi; Chiou, Chien-Shun; Chiang-Ni, Chuan; Wang, Shu-Ying; Tsai, Pei-Jane; Chuang, Woei-Jer; Lin, Yee-Shin; Liu, Ching-Chuan; Wu, Jiunn-Jong

2015-01-01

Clustered regularly interspaced short palindromic repeats (CRISPR) are the bacterial adaptive immune system against foreign nucleic acids. Given the variable nature of CRISPR, it could be a good marker for molecular epidemiology. Group A streptococcus is one of the major human pathogens. It has two CRISPR loci, including CRISPR01 and CRISPR02. The aim of this study was to analyze the distribution of CRISPR-associated gene cassettes (cas) and CRISPR arrays in highly prevalent emm types. The cas cassette and CRISPR array in two CRISPR loci were analyzed in a total of 332 strains, including emm1, emm3, emm4, emm12, and emm28 strains. The CRISPR type was defined by the spacer content of each CRISPR array. All strains had at least one cas cassette or CRISPR array. More than 90% of the spacers were found in one emm type, specifically. Comparing the consistency between emm and CRISPR types by Simpson's index of diversity and the adjusted Wallace coefficient, CRISPR01 type was concordant to emm type, and CRISPR02 showed unidirectional congruence to emm type, suggesting that at least for the majority of isolates causing infection in high income countries, the emm type can be inferred from CRISPR analysis, which can further discriminate isolates sharing the same emm type.

Effect of degree of urbanisation on age and sex-specific asthma prevalence in Swedish preschool children.

PubMed

Bröms, Kristina; Norbäck, Dan; Eriksson, Margaretha; Sundelin, Claes; Svärdsudd, Kurt

2009-08-20

There are few studies on age and sex-specific asthma prevalence in the age range 1-6 years. The purpose of this report was to estimate age and sex specific asthma prevalence in preschool children and to analyse the influence of possible demographic and geographic determinants. All 70 allergen avoidance day-care centres and 140 matched ordinary day-care centres across Sweden were sampled. The parents of all 8,757 children attending these day-care centres received the International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire, supplemented with questions on medical treatment, physician assessed asthma diagnosis, and other asthma related questions. The response rate was 68%. The age specific asthma prevalence, adjusted for the underlying municipality population size, was among boys 9.7% at age 1, 11.1% at age 2, 11.4 at age 3, 10.5 at age 4, 8.7 at age 5, and 6.4 at age 6. The corresponding proportions among girls were 8.9%, 9.9%, 9.8%, 8.8%, 7.0%, and 5.0%, on average 9.6% for boys and 8.2% for girls, altogether 8.9%. In addition to age and sex the prevalence increased by municipality population density, a proxy for degree of urbanisation. Moreover, there was a remaining weak geographical gradient with increasing prevalence towards the north and the west. The age-specific asthma prevalence was curvilinear with a peak around age 3 and somewhat higher for boys than for girls. The asthma prevalence increased in a slowly accelerating pace by municipality population density as a proxy for degree of urbanisation.

Prevalence Estimates of Combat-Related PTSD: A Critical Review

PubMed Central

Richardson, Lisa K.; Frueh, B. Christopher; Acierno, Ronald

2010-01-01

Objective To provide a critical review of prevalence estimates of combat-related PTSD among military personnel and veterans, and of the relevant factors that may account for the variability of estimates within and across cohorts, including methodological and conceptual factors accounting for differences in prevalence rates across nations, conflicts/wars, and studies. Method We examined MEDLINE and PsycINFO databases for literature on combat-related PTSD. The following terms were used independently and in combinations in this search: PTSD, combat, veterans, military, epidemiology, prevalence. Results The point prevalence of combat-related PTSD in US military veterans since the Vietnam War ranges from about 2 – 17%. Studies of recent conflicts suggest that combat-related PTSD afflicts between 4 – 17% of US Iraq War veterans, but only 3 – 6% of returning UK Iraq War veterans. Thus, the prevalence range is narrower and tends to have a lower ceiling among combat veterans of non-US Western nations. Variability in prevalence is likely due to differences in sampling strategies; measurement strategies; inclusion and measurement of the DSM-IV clinically significant impairment criterion; timing and latency of assessment and potential for recall bias; and combat experiences. Prevalence rates are also likely affected by issues related to PTSD course, chronicity, and comorbidity; symptom overlap with other psychiatric disorders; and sociopolitical and cultural factors that may vary over time and by nation. Conclusions The disorder represents a significant and costly illness to veterans, their families, and society as a whole. However, further carefully conceptualized research is needed to advance our understanding of disorder prevalence, as well as associated information on course, phenomenology, protective factors, treatment, and economic costs. PMID:20073563

Estimated prevalence of dengue viremia in Puerto Rican blood donations, 1995 through 2010.

PubMed

Petersen, Lyle R; Tomashek, Kay M; Biggerstaff, Brad J

2012-08-01

Dengue virus (DENV) nucleic acid amplification testing of blood donations during epidemics in endemic locations, including Puerto Rico, has suggested possible sizable transfusion transmission risk. Estimates of the long-term prevalence of DENV viremic donations will help evaluate the potential magnitude of this risk in Puerto Rico. Estimates of the prevalence of DENV viremia in the Puerto Rican population at large from 1995 through 2010 were derived from dengue case reports and their onset dates obtained from islandwide surveillance, estimates of case underreporting, and extant data on the duration of DENV viremia and the unapparent-to-apparent dengue infection ratio. Under the assumptions that viremia prevalence in blood donors was similar to that of the population at large and that symptomatic persons do not donate, statistical resampling methods were used to estimate the prevalence of dengue viremia in blood donations. Over the 16-year period, the maximum and mean daily prevalences of dengue viremia (per 10,000) in blood donations in Puerto Rico were estimated at 45.0 (95% confidence interval [CI], 36.5-55.4) and 7.0 (95% CI, 3.9-10.1), respectively. Prevalence varied considerably by season and year. These data suggest a substantial prevalence of DENV viremia in Puerto Rican blood donations, particularly during outbreaks. © 2012 American Association of Blood Banks.

Ecological association between HIV and concurrency point-prevalence in South Africa's ethnic groups.

PubMed

Kenyon, Chris

2013-11-01

HIV prevalence between different ethnic groups within South Africa exhibits considerable variation. Numerous authors believe that elevated sexual partner concurrency rates are important in the spread of HIV. Few studies have, however, investigated if differential concurrency rates could explain differential HIV spread within ethnic groups in South Africa. This ecological analysis, explores how much of the variation in HIV prevalence by ethnic group is explained by differential concurrency rates. Using a nationally representative survey (the South African National HIV Prevalence, HIV Incidence, Behaviour and Communication Survey, 2005) the HIV prevalence in each of eight major ethnic groups was calculated. Linear regression analysis was used to assess the association between an ethnic group's HIV prevalence and the point-prevalence of concurrency. Results showed that HIV prevalence rates varied considerably between South Africa's ethnic groups. This applied to both different racial groups and to different ethnic groups within the black group. The point-prevalence of concurrency by ethnic group was strongly associated with HIV prevalence (R(2) = 0.83; p = 0.001). Tackling the key drivers of high HIV transmission in this population may benefit from more emphasis on partner reduction interventions.

Prevalence of Chronic Hypoparathyroidism in a Mediterranean Region as Estimated by the Analysis of Anonymous Healthcare Database.

PubMed

Cianferotti, Luisella; Parri, Simone; Gronchi, Giorgio; Marcucci, Gemma; Cipriani, Cristiana; Pepe, Jessica; Raglianti, Marco; Minisola, Salvatore; Brandi, Maria Luisa

2018-03-08

Epidemiological data on prevalence and incidence of chronic hypoparathyroidism are still scarce. This study aimed to establish prevalence of chronic hypoparathyroidism and incidence of surgical hypoparathyroidism using the analysis of electronic anonymous public health care database. Data referred to a 5-year period (2009-2013, Region of Tuscany, Italy, as a sample representative of the whole Mediterranean/European population, estimated mean population: 3,750,000 inhabitants) were retrieved by the analysis of pharmaceutical distribution dataset, containing data related to drugs reimbursed by public health system, hospital discharge and procedures codes, and ICD9 exemption codes for chronic diseases. The application of a specific algorithm was applied to indirectly identify people with chronic hypoparathyroidism as assuming chronic therapy with active vitamin D metabolites (AVDM). The number of people taking AVDM for a period equal to or longer than 6 months till the end of the study period, with ICD9 exemption code for hypoparathyroidism, and with a disease-related discharge code were identified. Within this restricted group, patients with chronic kidney disease and osteoporosis were excluded. The indirect estimate of chronic hypoparathyroidism in a European Mediterranean subpopulation by means of the analysis of chronic therapy with AVDM was 27/100,000 inhabitants (female:male ratio = 2.2:1), with a mean age of 63.5 ± 16.7 years. The risk of developing hypoparathyroidism after neck surgery was 1.5%. While the epidemiological approaches based on disease code and hospital discharge code greatly underestimates the prevalence of hypoparathyroidism, the indirect estimate of this disease through the analysis of prescriptions of AVDM in a European region is in line with the results of studies performed in other regions of the world.

Estimation of the Prevalence of Autism Spectrum Disorder in South Korea, Revisited

ERIC Educational Resources Information Center

Pantelis, Peter C.; Kennedy, Daniel P.

2016-01-01

Two-phase designs in epidemiological studies of autism prevalence introduce methodological complications that can severely limit the precision of resulting estimates. If the assumptions used to derive the prevalence estimate are invalid or if the uncertainty surrounding these assumptions is not properly accounted for in the statistical inference…

Prevalence, Duration and Severity of Parkinson's Disease in Germany: A Combined Meta-Analysis from Literature Data and Outpatient Samples.

PubMed

Enders, Dirk; Balzer-Geldsetzer, Monika; Riedel, Oliver; Dodel, Richard; Wittchen, Hans-Ulrich; Sensken, Sven-Christian; Wolff, Björn; Reese, Jens-Peter

2017-01-01

Epidemiological data on the prevalence of Parkinson's disease (PD) in Germany are limited. The aims of this study were to estimate the age- and gender-specific prevalence of PD in Germany as well as the severity and illness duration. A systematic literature search was performed in 5 different databases. European studies were included if they reported age- and gender-specific numbers of prevalence rates of PD. Meta-analytic approaches were applied to derive age- and gender-specific pooled prevalence estimates. Data of 4 German outpatient samples were incorporated to calculate the proportion of patients with PD in Germany grouped by Hoehn and Yahr (HY) stages and disease duration. In the German population, 178,169 cases of PD were estimated (prevalence: 217.22/100,000). The estimated relative illness duration was 40% with less than 5 years, 31% with 5-9 years, and 29% with more than 9 years. The proportions for different HY stages were estimated at 13% (I), 30% (II), 35% (III), 17% (IV), and 4% (V), respectively. Key Message: We provide an up-to-date estimation of age- and gender-specific as well as severity-based prevalence figures for PD in Germany. Further community studies are needed to estimate population-based severity distributions and distributions of non-motor symptoms in PD. © 2017 S. Karger AG, Basel.

Predictors and Impact of Self-Reported Suboptimal Effort on Estimates of Prevalence of HIV-Associated Neurocognitive Disorders.

PubMed

Levine, Andrew J; Martin, Eileen; Sacktor, Ned; Munro, Cynthia; Becker, James

2017-06-01

Prevalence estimates of HIV-associated neurocognitive disorders (HAND) may be inflated. Estimates are determined via cohort studies in which participants may apply suboptimal effort on neurocognitive testing, thereby inflating estimates. Additionally, fluctuating HAND severity over time may be related to inconsistent effort. To address these hypotheses, we characterized effort in the Multicenter AIDS Cohort Study. After neurocognitive testing, 935 participants (525 HIV- and 410 HIV+) completed the visual analog effort scale (VAES), rating their effort from 0% to 100%. Those with <100% then indicated the reason(s) for suboptimal effort. K-means cluster analysis established 3 groups: high (mean = 97%), moderate (79%), and low effort (51%). Rates of HAND and other characteristics were compared between the groups. Linear regression examined the predictors of VAES score. Data from 57 participants who completed the VAES at 2 visits were analyzed to characterize the longitudinal relationship between effort and HAND severity. Fifty-two percent of participants reported suboptimal effort (<100%), with no difference between serostatus groups. Common reasons included "tired" (43%) and "distracted" (36%). The lowest effort group had greater asymptomatic neurocognitive impairment and minor neurocognitive disorder diagnosis (25% and 33%) as compared with the moderate (23% and 15%) and the high (12% and 9%) effort groups. Predictors of suboptimal effort were self-reported memory impairment, African American race, and cocaine use. Change in effort between baseline and follow-up correlated with change in HAND severity. Suboptimal effort seems to inflate estimated HAND prevalence and explain fluctuation of severity over time. A simple modification of study protocols to optimize effort is indicated by the results.

Comparison of type 2 diabetes prevalence estimates in Saudi Arabia from a validated Markov model against the International Diabetes Federation and other modelling studies

PubMed Central

Al-Quwaidhi, Abdulkareem J.; Pearce, Mark S.; Sobngwi, Eugene; Critchley, Julia A.; O’Flaherty, Martin

2014-01-01

Aims To compare the estimates and projections of type 2 diabetes mellitus (T2DM) prevalence in Saudi Arabia from a validated Markov model against other modelling estimates, such as those produced by the International Diabetes Federation (IDF) Diabetes Atlas and the Global Burden of Disease (GBD) project. Methods A discrete-state Markov model was developed and validated that integrates data on population, obesity and smoking prevalence trends in adult Saudis aged ≥25 years to estimate the trends in T2DM prevalence (annually from 1992 to 2022). The model was validated by comparing the age- and sex-specific prevalence estimates against a national survey conducted in 2005. Results Prevalence estimates from this new Markov model were consistent with the 2005 national survey and very similar to the GBD study estimates. Prevalence in men and women in 2000 was estimated by the GBD model respectively at 17.5% and 17.7%, compared to 17.7% and 16.4% in this study. The IDF estimates of the total diabetes prevalence were considerably lower at 16.7% in 2011 and 20.8% in 2030, compared with 29.2% in 2011 and 44.1% in 2022 in this study. Conclusion In contrast to other modelling studies, both the Saudi IMPACT Diabetes Forecast Model and the GBD model directly incorporated the trends in obesity prevalence and/or body mass index (BMI) to inform T2DM prevalence estimates. It appears that such a direct incorporation of obesity trends in modelling studies results in higher estimates of the future prevalence of T2DM, at least in countries where obesity has been rapidly increasing. PMID:24447810

Prevalence of Transgender Depends on the "Case" Definition: A Systematic Review.

PubMed

Collin, Lindsay; Reisner, Sari L; Tangpricha, Vin; Goodman, Michael

2016-04-01

A systematic review and meta-analysis was conducted to evaluate how various definitions of transgender affect prevalence estimates. To evaluate the epidemiology of transgender and examine how various definitions of transgender affect prevalence estimates and to compare findings across studies that used different methodologies, in different countries, and over different periods. PubMed, EMBASE, and Medline were searched to identify studies reporting prevalence estimates of transgender in a population. All studies were grouped based on the case definition applied to the numerator. Summary estimates were derived using a random-effects model for total prevalence of transgender and for male-to-female and female-to-male subgroups. Overall and stratum-specific meta-prevalence estimates (mPs) and 95% confidence intervals (CIs) were accompanied by tests for heterogeneity and meta-regressions to assess sources of heterogeneity. The main outcome measure was population prevalence of transgender. Secondary outcomes included gender-specific prevalence estimates for male-to-female and female to male subgroups. Thirty-two studies met the inclusion criteria for systematic review. Of those, 27 studies provided necessary data for a meta-analysis. Overall mP estimates per 100,000 population were 9.2 (95% CI = 4.9-13.6) for surgical or hormonal gender affirmation therapy and 6.8 (95% CI = 4.6-9.1) for transgender-related diagnoses. Of studies assessing self-reported transgender identity, the mP was 871 (95% CI = 519-1,224); however, this result was influenced by a single outlier study. After removal of that study, the mP changed to 355 (95% CI = 144-566). Significant heterogeneity was observed in most analyses. The empirical literature on the prevalence of transgender highlights the importance of adhering to specific case definitions because the results can range by orders of magnitude. Standardized and routine collection of data on transgender status and gender identity is

Decision-model estimation of the age-specific disability weight for schistosomiasis japonica: a systematic review of the literature.

PubMed

Finkelstein, Julia L; Schleinitz, Mark D; Carabin, Hélène; McGarvey, Stephen T

2008-03-05

Schistosomiasis is among the most prevalent parasitic infections worldwide. However, current Global Burden of Disease (GBD) disability-adjusted life year estimates indicate that its population-level impact is negligible. Recent studies suggest that GBD methodologies may significantly underestimate the burden of parasitic diseases, including schistosomiasis. Furthermore, strain-specific disability weights have not been established for schistosomiasis, and the magnitude of human disease burden due to Schistosoma japonicum remains controversial. We used a decision model to quantify an alternative disability weight estimate of the burden of human disease due to S. japonicum. We reviewed S. japonicum morbidity data, and constructed decision trees for all infected persons and two age-specific strata, <15 years (y) and > or =15 y. We conducted stochastic and probabilistic sensitivity analyses for each model. Infection with S. japonicum was associated with an average disability weight of 0.132, with age-specific disability weights of 0.098 (<15 y) and 0.186 (> or =15 y). Re-estimated disability weights were seven to 46 times greater than current GBD measures; no simulations produced disability weight estimates lower than 0.009. Nutritional morbidities had the greatest contribution to the S. japonicum disability weight in the <15 y model, whereas major organ pathologies were the most critical variables in the older age group. GBD disability weights for schistosomiasis urgently need to be revised, and species-specific disability weights should be established. Even a marginal increase in current estimates would result in a substantial rise in the estimated global burden of schistosomiasis, and have considerable implications for public health prioritization and resource allocation for schistosomiasis research, monitoring, and control.

Decision-Model Estimation of the Age-Specific Disability Weight for Schistosomiasis Japonica: A Systematic Review of the Literature

PubMed Central

Finkelstein, Julia L.; Schleinitz, Mark D.; Carabin, Hélène; McGarvey, Stephen T.

2008-01-01

Schistosomiasis is among the most prevalent parasitic infections worldwide. However, current Global Burden of Disease (GBD) disability-adjusted life year estimates indicate that its population-level impact is negligible. Recent studies suggest that GBD methodologies may significantly underestimate the burden of parasitic diseases, including schistosomiasis. Furthermore, strain-specific disability weights have not been established for schistosomiasis, and the magnitude of human disease burden due to Schistosoma japonicum remains controversial. We used a decision model to quantify an alternative disability weight estimate of the burden of human disease due to S. japonicum. We reviewed S. japonicum morbidity data, and constructed decision trees for all infected persons and two age-specific strata, <15 years (y) and ≥15 y. We conducted stochastic and probabilistic sensitivity analyses for each model. Infection with S. japonicum was associated with an average disability weight of 0.132, with age-specific disability weights of 0.098 (<15 y) and 0.186 (≥15 y). Re-estimated disability weights were seven to 46 times greater than current GBD measures; no simulations produced disability weight estimates lower than 0.009. Nutritional morbidities had the greatest contribution to the S. japonicum disability weight in the <15 y model, whereas major organ pathologies were the most critical variables in the older age group. GBD disability weights for schistosomiasis urgently need to be revised, and species-specific disability weights should be established. Even a marginal increase in current estimates would result in a substantial rise in the estimated global burden of schistosomiasis, and have considerable implications for public health prioritization and resource allocation for schistosomiasis research, monitoring, and control. PMID:18320018

Refusal bias in HIV prevalence estimates from nationally representative seroprevalence surveys.

PubMed

Reniers, Georges; Eaton, Jeffrey

2009-03-13

To assess the relationship between prior knowledge of one's HIV status and the likelihood to refuse HIV testing in populations-based surveys and explore its potential for producing bias in HIV prevalence estimates. Using longitudinal survey data from Malawi, we estimate the relationship between prior knowledge of HIV-positive status and subsequent refusal of an HIV test. We use that parameter to develop a heuristic model of refusal bias that is applied to six Demographic and Health Surveys, in which refusal by HIV status is not observed. The model only adjusts for refusal bias conditional on a completed interview. Ecologically, HIV prevalence, prior testing rates and refusal for HIV testing are highly correlated. Malawian data further suggest that amongst individuals who know their status, HIV-positive individuals are 4.62 (95% confidence interval, 2.60-8.21) times more likely to refuse testing than HIV-negative ones. On the basis of that parameter and other inputs from the Demographic and Health Surveys, our model predicts downward bias in national HIV prevalence estimates ranging from 1.5% (95% confidence interval, 0.7-2.9) for Senegal to 13.3% (95% confidence interval, 7.2-19.6) for Malawi. In absolute terms, bias in HIV prevalence estimates is negligible for Senegal but 1.6 (95% confidence interval, 0.8-2.3) percentage points for Malawi. Downward bias is more severe in urban populations. Because refusal rates are higher in men, seroprevalence surveys also tend to overestimate the female-to-male ratio of infections. Prior knowledge of HIV status informs decisions to participate in seroprevalence surveys. Informed refusals may produce bias in estimates of HIV prevalence and the sex ratio of infections.

Clustered Regularly Interspaced Short Palindromic Repeats Are emm Type-Specific in Highly Prevalent Group A Streptococci

PubMed Central

Zheng, Po-Xing; Chan, Yuen-Chi; Chiou, Chien-Shun; Chiang-Ni, Chuan; Wang, Shu-Ying; Tsai, Pei-Jane; Chuang, Woei-Jer; Lin, Yee-Shin; Liu, Ching-Chuan; Wu, Jiunn-Jong

2015-01-01

Clustered regularly interspaced short palindromic repeats (CRISPR) are the bacterial adaptive immune system against foreign nucleic acids. Given the variable nature of CRISPR, it could be a good marker for molecular epidemiology. Group A streptococcus is one of the major human pathogens. It has two CRISPR loci, including CRISPR01 and CRISPR02. The aim of this study was to analyze the distribution of CRISPR-associated gene cassettes (cas) and CRISPR arrays in highly prevalent emm types. The cas cassette and CRISPR array in two CRISPR loci were analyzed in a total of 332 strains, including emm1, emm3, emm4, emm12, and emm28 strains. The CRISPR type was defined by the spacer content of each CRISPR array. All strains had at least one cas cassette or CRISPR array. More than 90% of the spacers were found in one emm type, specifically. Comparing the consistency between emm and CRISPR types by Simpson’s index of diversity and the adjusted Wallace coefficient, CRISPR01 type was concordant to emm type, and CRISPR02 showed unidirectional congruence to emm type, suggesting that at least for the majority of isolates causing infection in high income countries, the emm type can be inferred from CRISPR analysis, which can further discriminate isolates sharing the same emm type. PMID:26710228

Prevalence of dilated cardiomyopathy in Doberman Pinschers in various age groups.

PubMed

Wess, G; Schulze, A; Butz, V; Simak, J; Killich, M; Keller, L J M; Maeurer, J; Hartmann, K

2010-01-01

Dilated cardiomyopathy (DCM) in Doberman Pinschers is an autosomal dominant inherited disease. The prevalence of DCM in Doberman Pinschers of various age groups in Europe is currently unknown, but this information would be important to develop recommendations for screening programs. To evaluate the prevalence of cardiomyopathy in various age groups of Dobermans. Seven hundred and seventy-five examinations in 412 Doberman Pinschers. Dogs were included in a prospective longitudinal cohort study. Each examination included echocardiography and 24-hour ECG (Holter) examination. A cut-off value of >100 ventricular premature contractions (VPCs) per 24 hours on Holter examination or abnormal echocardiography was considered diagnostic for cardiomyopathy. The cumulative prevalence included all dogs with DCM and healthy dogs >7 years of age. DCM prevalence in various age groups was as follows: age group 1 (1 to <2 years) 3.3%, age group 2 (2 to <4 years) 9.9%, age group 3 (4 to <6 years) 12.5%, age group 4 (6 to <8 years) 43.6%, and age group 5 (>8 years) 44.1%. The cumulative prevalence of Doberman Pinscher cardiomyopathy was 58.2%. There was an equal sex distribution, but male dogs showed earlier echocardiographic changes than did female dogs, which had significantly more VPCs. The prevalence of Doberman cardiomyopathy is very high in Europe. Disease manifestation and progression are different between male and female dogs. Yearly screening for DCM by Holter examination and echocardiography is recommended, starting at 2 years of age.

Estimating time-dependent ROC curves using data under prevalent sampling.

PubMed

Li, Shanshan

2017-04-15

Prevalent sampling is frequently a convenient and economical sampling technique for the collection of time-to-event data and thus is commonly used in studies of the natural history of a disease. However, it is biased by design because it tends to recruit individuals with longer survival times. This paper considers estimation of time-dependent receiver operating characteristic curves when data are collected under prevalent sampling. To correct the sampling bias, we develop both nonparametric and semiparametric estimators using extended risk sets and the inverse probability weighting techniques. The proposed estimators are consistent and converge to Gaussian processes, while substantial bias may arise if standard estimators for right-censored data are used. To illustrate our method, we analyze data from an ovarian cancer study and estimate receiver operating characteristic curves that assess the accuracy of the composite markers in distinguishing subjects who died within 3-5 years from subjects who remained alive. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A Novel Group-Fused Sparse Partial Correlation Method for Simultaneous Estimation of Functional Networks in Group Comparison Studies.

PubMed

Liang, Xiaoyun; Vaughan, David N; Connelly, Alan; Calamante, Fernando

2018-05-01

The conventional way to estimate functional networks is primarily based on Pearson correlation along with classic Fisher Z test. In general, networks are usually calculated at the individual-level and subsequently aggregated to obtain group-level networks. However, such estimated networks are inevitably affected by the inherent large inter-subject variability. A joint graphical model with Stability Selection (JGMSS) method was recently shown to effectively reduce inter-subject variability, mainly caused by confounding variations, by simultaneously estimating individual-level networks from a group. However, its benefits might be compromised when two groups are being compared, given that JGMSS is blinded to other groups when it is applied to estimate networks from a given group. We propose a novel method for robustly estimating networks from two groups by using group-fused multiple graphical-lasso combined with stability selection, named GMGLASS. Specifically, by simultaneously estimating similar within-group networks and between-group difference, it is possible to address inter-subject variability of estimated individual networks inherently related with existing methods such as Fisher Z test, and issues related to JGMSS ignoring between-group information in group comparisons. To evaluate the performance of GMGLASS in terms of a few key network metrics, as well as to compare with JGMSS and Fisher Z test, they are applied to both simulated and in vivo data. As a method aiming for group comparison studies, our study involves two groups for each case, i.e., normal control and patient groups; for in vivo data, we focus on a group of patients with right mesial temporal lobe epilepsy.

Estimating the Prevalence of Childhood Obesity in Alaska Using Partial, Nonrandom Measurement Data

PubMed Central

Boles, Myde; Fink, Karol; Topol, Rebecca; Fenaughty, Andrea

2016-01-01

Although monitoring childhood obesity prevalence is critical for state public health programs to assess trends and the effectiveness of interventions, few states have comprehensive body mass index measurement systems in place. In some states, however, assorted school districts collect measurements on student height and weight as part of annual health screenings. To estimate childhood obesity prevalence in Alaska, we created a logistic regression model using such annual measurements along with public data on demographics and socioeconomic status. Our mixed-effects model-generated prevalence estimates validated well against weighted estimates, with 95% confidence intervals overlapping between methodologies among 7 of 8 participating school districts. Our methodology accounts for variation in school-level and student-level demographic factors across the state, and the approach we describe can be applied by other states that have existing nonrandom student measurement data to estimate childhood obesity prevalence. PMID:27010843

Cancer prevalence in Italian cancer registry areas: the ITAPREVAL study. ITAPREVAL Working Group.

PubMed

Micheli, A; Francisci, S; Krogh, V; Rossi, A G; Crosignani, P

1999-01-01

To present data on cancer prevalence for the areas covered by Italian cancer registries, by using a standardized set of data collection and elaboration criteria, and a single method of data analysis. Data on over 250,000 patients with cancer, diagnosed between 1978 and 1992, from 11 Italian cancer registries covering about 12% of the Italian population were collected, validated and analyzed according to the unified protocol of the ITAPREVAL project. The method implemented in the PREVAL computer program was used to provide prevalence estimates for the period covered by cancer registration. The total prevalence for each registry and for the pool of all registries was then estimated by correcting for incomplete observations due to the period in which the registration was not yet activated. All prevalence estimates were for 1992. Prevalence figures are presented by cancer site, age, sex, years from diagnosis and registry area. For all malignancies combined, total prevalence ranged from 1,350 per 100,000 inhabitants in Ragusa to 3,650 per 100,000 inhabitants in Romagna, the ratio between these two extremes being 2.7. For the pool of the areas covered by registration cancer prevalence was 3,100 per 100,000 females and 2,250 per 100,000 males. About a third of the total female cases and about half the male cases were diagnosed in the previous five years. Among those aged over 75 years, total prevalence was higher for males than for females: 11,300 versus 8,900 per 100,000 respectively. This is the first large-scale estimate of the burden of cancer in Italy. It is also one of the first studies in the world which was aimed to study cancer prevalence in detail. These data are necessary for predicting health service needs and help in the evaluation of differences in health service demand by sex, age and Italian regions.

Use of Pathogen-Specific Antibody Biomarkers to Estimate Waterborne Infections in Population-Based Settings.

PubMed

Exum, Natalie G; Pisanic, Nora; Granger, Douglas A; Schwab, Kellogg J; Detrick, Barbara; Kosek, Margaret; Egorov, Andrey I; Griffin, Shannon M; Heaney, Christopher D

2016-09-01

This review discusses the utility of pathogen-specific antibody biomarkers for improving estimates of the population burden of waterborne infections, assessing the fraction of infections that can be prevented by specific water treatments, and understanding transmission routes and the natural history and ecology of disease in different populations (including asymptomatic infection rates). We review recent literature on the application of pathogen-specific antibody response data to estimate incidence and prevalence of acute infections and their utility to assess the contributions of waterborne transmission pathways. Advantages and technical challenges associated with the use of serum versus minimally invasive salivary antibody biomarkers in cross-sectional and prospective surveys are discussed. We highlight recent advances and challenges and outline future directions for research, development, and application of antibody-based and other immunological biomarkers of waterborne infections.

The impact of proposed changes to ICD-11 on estimates of PTSD prevalence and comorbidity.

PubMed

Wisco, Blair E; Miller, Mark W; Wolf, Erika J; Kilpatrick, Dean; Resnick, Heidi S; Badour, Christal L; Marx, Brian P; Keane, Terence M; Rosen, Raymond C; Friedman, Matthew J

2016-06-30

The World Health Organization's posttraumatic stress disorder (PTSD) work group has published a proposal for the forthcoming edition of the International Classification of Diseases (ICD-11) that would yield a very different diagnosis relative to DSM-5. This study examined the impact of the proposed ICD-11 changes on PTSD prevalence relative to the ICD-10 and DSM-5 definitions and also evaluated the extent to which these changes would accomplish the stated aim of reducing the comorbidity associated with PTSD. Diagnostic prevalence estimates were compared using a U.S. national community sample and two U.S. Department of Veterans Affairs clinical samples. The ICD-11 definition yielded prevalence estimates 10-30% lower than DSM-5 and 25% and 50% lower than ICD-10 with no reduction in the prevalence of common comorbidities. Findings suggest that by constraining the diagnosis to a narrower set of symptoms, the proposed ICD-11 criteria set would substantially reduce the number of individuals with the disorder. These findings raise doubt about the extent to which the ICD-11 proposal would achieve the aim of reducing comorbidity associated with PTSD and highlight the public health and policy implications of such a redefinition. Published by Elsevier Ireland Ltd.

Evaluation of test-strategies for estimating probability of low prevalence of paratuberculosis in Danish dairy herds.

PubMed

Sergeant, E S G; Nielsen, S S; Toft, N

2008-06-15

Paratuberculosis is a chronic infection affecting cattle and other ruminants. In the dairy industry, losses due to paratuberculosis can be substantial in infected herds and several countries have implemented national programmes based on herd-classification to manage the disease. The aim of this study was to develop a method to estimate the probability of low within-herd prevalence of paratuberculosis for Danish dairy herds. A stochastic simulation model was developed using the R programming environment. Features of this model included: use of age-specific estimates of test-sensitivity and specificity; use of a distribution of observed values (rather than a fixed, low value) for design prevalence; and estimates of the probability of low prevalence (PrLow) based on a specific number of test-positive animals, rather than for a result less than or equal to a specified cut-point number of reactors. Using this model, five herd-testing strategies were evaluated: (1) milk-ELISA on all lactating cows; (2) milk-ELISA on lactating cows4 years old; (4) faecal culture on all lactating cows; and (5) milk-ELISA plus faecal culture in series on all lactating cows. The five testing strategies were evaluated using observed milk-ELISA results from 19 Danish dairy herds as well as for simulated results from the same herds assuming that they were uninfected. Whole-herd milk-ELISA was the preferred strategy, and considered the most cost-effective strategy of the five alternatives. The five strategies were all efficient in detecting infection, i.e. estimating a low PrLow in infected herds, however, PrLow estimates for milk-ELISA on age-cohorts were too low in simulated uninfected herds and the strategies involving faecal culture were too expensive to be of practical interest. For simulated uninfected herds, whole-herd milk-ELISA resulted in median PrLow values>0.9 for most herds, depending on herd size and age-structure. None of the

Incidence and prevalence of Toxoplasma gondii infection in women in France, 1980-2020: model-based estimation.

PubMed

Nogareda, F; Le Strat, Y; Villena, I; De Valk, H; Goulet, V

2014-08-01

Toxoplasmosis is a worldwide zoonosis due to Toxoplasma gondii, a ubiquitous protozoan parasite of warm-blooded animals including humans. In pregnant women, primary infection can cause congenital toxoplasmosis resulting in severe malformations in the newborn. Since 1978, public health authorities in France have implemented a congenital toxoplasmosis prevention programme, including monthly serological screening of all seronegative pregnant women, and treatment in case of seroconversion. However, this programme does not produce systematic surveillance data on incidence and prevalence. Our objective was to estimate the incidence and prevalence of T. gondii infection, and the incidence of seroconversion during pregnancy in women in France. We used a catalytic model to estimate incidence and prevalence of Toxoplasma infection between 1980 and 2020 in women of childbearing age. We used age- and time-specific seroprevalence data obtained from the National Perinatal Surveys (NPS) conducted in 1995, 2003 and 2010. We assumed that incidence depends both on age and calendar time, and can be expressed as the product of two unknown functions. We also estimated incidence of seroconversion during pregnancy in 2010 from the NPS and the National Surveillance of Congenital Toxoplasmosis (ToxoSurv). We combined data of 42208 women aged 15-45 years with serology available from the three NPS. For women aged 30 years the modelled incidence decreased from 7·5/1000 susceptible women in 1980 to 3·5/1000 in 2000. In 2010 the incidence was 2·4/1000. The predicted incidence and prevalence for 2020 was 1·6/1000 and 27%, respectively. The incidence of seroconversion during pregnancy in 2010 was estimated at 2·1/1000 susceptible pregnant women (95% CI 1·3-3·1) from the NPS and 1·9 (95% CI 1·8-2·1) from ToxoSurv. Incidence and prevalence of Toxoplasma infection has decreased markedly during the last 30 years. This decrease may be explained by a lower exposure to the parasite by changes

The impact of fecal sample processing on prevalence estimates for antibiotic-resistant Escherichia coli.

PubMed

Omulo, Sylvia; Lofgren, Eric T; Mugoh, Maina; Alando, Moshe; Obiya, Joshua; Kipyegon, Korir; Kikwai, Gilbert; Gumbi, Wilson; Kariuki, Samuel; Call, Douglas R

2017-05-01

Investigators often rely on studies of Escherichia coli to characterize the burden of antibiotic resistance in a clinical or community setting. To determine if prevalence estimates for antibiotic resistance are sensitive to sample handling and interpretive criteria, we collected presumptive E. coli isolates (24 or 95 per stool sample) from a community in an urban informal settlement in Kenya. Isolates were tested for susceptibility to nine antibiotics using agar breakpoint assays and results were analyzed using generalized linear mixed models. We observed a <3-fold difference between prevalence estimates based on freshly isolated bacteria when compared to isolates collected from unprocessed fecal samples or fecal slurries that had been stored at 4°C for up to 7days. No time-dependence was evident (P>0.1). Prevalence estimates did not differ for five distinct E. coli colony morphologies on MacConkey agar plates (P>0.2). Successive re-plating of samples for up to five consecutive days had little to no impact on prevalence estimates. Finally, culturing E. coli under different conditions (with 5% CO 2 or micro-aerobic) did not affect estimates of prevalence. For the conditions tested in these experiments, minor modifications in sample processing protocols are unlikely to bias estimates of the prevalence of antibiotic-resistance for fecal E. coli. Copyright © 2017 Elsevier B.V. All rights reserved.

Bayesian Hierarchical Grouping: perceptual grouping as mixture estimation

PubMed Central

Froyen, Vicky; Feldman, Jacob; Singh, Manish

2015-01-01

We propose a novel framework for perceptual grouping based on the idea of mixture models, called Bayesian Hierarchical Grouping (BHG). In BHG we assume that the configuration of image elements is generated by a mixture of distinct objects, each of which generates image elements according to some generative assumptions. Grouping, in this framework, means estimating the number and the parameters of the mixture components that generated the image, including estimating which image elements are “owned” by which objects. We present a tractable implementation of the framework, based on the hierarchical clustering approach of Heller and Ghahramani (2005). We illustrate it with examples drawn from a number of classical perceptual grouping problems, including dot clustering, contour integration, and part decomposition. Our approach yields an intuitive hierarchical representation of image elements, giving an explicit decomposition of the image into mixture components, along with estimates of the probability of various candidate decompositions. We show that BHG accounts well for a diverse range of empirical data drawn from the literature. Because BHG provides a principled quantification of the plausibility of grouping interpretations over a wide range of grouping problems, we argue that it provides an appealing unifying account of the elusive Gestalt notion of Prägnanz. PMID:26322548

Defining Risk Groups to Yellow Fever Vaccine-Associated Viscerotropic Disease in the Absence of Denominator Data

PubMed Central

Seligman, Stephen J.; Cohen, Joel E.; Itan, Yuval; Casanova, Jean-Laurent; Pezzullo, John C.

2014-01-01

Several risk groups are known for the rare but serious, frequently fatal, viscerotropic reactions following live yellow fever virus vaccine (YEL-AVD). Establishing additional risk groups is hampered by ignorance of the numbers of vaccinees in factor-specific risk groups thus preventing their use as denominators in odds ratios (ORs). Here, we use an equation to calculate ORs using the prevalence of the factor-specific risk group in the population who remain well. The 95% confidence limits and P values can also be calculated. Moreover, if the estimate of the prevalence is imprecise, discrimination analysis can indicate the prevalence at which the confidence interval results in an OR of ∼1 revealing if the prevalence might be higher without yielding a non-significant result. These methods confirm some potential risk groups for YEL-AVD and cast doubt on another. They should prove useful in situations in which factor-specific risk group denominator data are not available. PMID:24394480

Defining risk groups to yellow fever vaccine-associated viscerotropic disease in the absence of denominator data.

PubMed

Seligman, Stephen J; Cohen, Joel E; Itan, Yuval; Casanova, Jean-Laurent; Pezzullo, John C

2014-02-01

Several risk groups are known for the rare but serious, frequently fatal, viscerotropic reactions following live yellow fever virus vaccine (YEL-AVD). Establishing additional risk groups is hampered by ignorance of the numbers of vaccinees in factor-specific risk groups thus preventing their use as denominators in odds ratios (ORs). Here, we use an equation to calculate ORs using the prevalence of the factor-specific risk group in the population who remain well. The 95% confidence limits and P values can also be calculated. Moreover, if the estimate of the prevalence is imprecise, discrimination analysis can indicate the prevalence at which the confidence interval results in an OR of ∼1 revealing if the prevalence might be higher without yielding a non-significant result. These methods confirm some potential risk groups for YEL-AVD and cast doubt on another. They should prove useful in situations in which factor-specific risk group denominator data are not available.

Prevalence of Estimated GFR Reporting Among US Clinical Laboratories

PubMed Central

Accetta, Nancy A.; Gladstone, Elisa H.; DiSogra, Charles; Wright, Elizabeth C.; Briggs, Michael; Narva, Andrew S.

2008-01-01

Background Routine laboratory reporting of estimated glomerular filtration rate (eGFR) may help clinicians detect kidney disease. The current national prevalence of eGFR reporting among clinical laboratories is unknown, thus the extent of the situation of laboratories not routinely reporting eGFR with serum creatinine (SCr) results is not quantified. Design Observational analysis. Setting National Kidney Disease Education Program survey of clinical laboratory conducted in 2006-7 by mail, Web, and telephone follow up. Participants A national random sample, 6,350 clinical laboratories, drawn from the Federal Clinical Laboratory Improvement Amendments database and stratified by six major laboratory types/groupings. Predictors Laboratory reports SCr results. Outcomes Reporting eGFR values along with SCr results. Measurements Percent of laboratories reporting eGFR along with reporting SCr, reporting protocol, eGFR formula used, and style of reporting cutoff values. Results Among laboratories reporting SCr, 38.4% report eGFR (physician offices, 25.8%; hospitals, 43.6%; independents, 38.9%; community clinics, 47.2%; health fair/insurance/public health, 45.5%; others, 43.2%). Physician office laboratories have a reporting prevalence lower than other laboratory types (p < 0.001). Among laboratories reporting eGFR, 66.7% do so routinely with all adult SCr determinations; 71.6% use the 4-variable Modification of Diet in Renal Disease Study equation; and 45.3% use the “>60 mL/min/1.73 m2” reporting convention. Independent laboratories are least likely to routinely report eGFR, (50.6%, p < .05) and most likely to report only when specifically requested (45.4%, p < 0.05). High-volume laboratories across all strata are more likely to report eGFR (p < 0.001). Limitations Self-reporting by laboratories, Federal database did not have names of laboratory directors/managers (intended respondents), assumed accuracy of Federal database for sample purposes. Conclusions Routine e

Interpreting ambiguous 'trace' results in Schistosoma mansoni CCA Tests: Estimating sensitivity and specificity of ambiguous results with no gold standard.

PubMed

Clements, Michelle N; Donnelly, Christl A; Fenwick, Alan; Kabatereine, Narcis B; Knowles, Sarah C L; Meité, Aboulaye; N'Goran, Eliézer K; Nalule, Yolisa; Nogaro, Sarah; Phillips, Anna E; Tukahebwa, Edridah Muheki; Fleming, Fiona M

2017-12-01

The development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous 'trace' result between 'positive' and 'negative', and much debate has focused on interpretation of traces results. We show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both Côte d'Ivoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population. Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries. Incorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence.

Composite Partial Likelihood Estimation Under Length-Biased Sampling, With Application to a Prevalent Cohort Study of Dementia

PubMed Central

Huang, Chiung-Yu; Qin, Jing

2013-01-01

The Canadian Study of Health and Aging (CSHA) employed a prevalent cohort design to study survival after onset of dementia, where patients with dementia were sampled and the onset time of dementia was determined retrospectively. The prevalent cohort sampling scheme favors individuals who survive longer. Thus, the observed survival times are subject to length bias. In recent years, there has been a rising interest in developing estimation procedures for prevalent cohort survival data that not only account for length bias but also actually exploit the incidence distribution of the disease to improve efficiency. This article considers semiparametric estimation of the Cox model for the time from dementia onset to death under a stationarity assumption with respect to the disease incidence. Under the stationarity condition, the semiparametric maximum likelihood estimation is expected to be fully efficient yet difficult to perform for statistical practitioners, as the likelihood depends on the baseline hazard function in a complicated way. Moreover, the asymptotic properties of the semiparametric maximum likelihood estimator are not well-studied. Motivated by the composite likelihood method (Besag 1974), we develop a composite partial likelihood method that retains the simplicity of the popular partial likelihood estimator and can be easily performed using standard statistical software. When applied to the CSHA data, the proposed method estimates a significant difference in survival between the vascular dementia group and the possible Alzheimer’s disease group, while the partial likelihood method for left-truncated and right-censored data yields a greater standard error and a 95% confidence interval covering 0, thus highlighting the practical value of employing a more efficient methodology. To check the assumption of stable disease for the CSHA data, we also present new graphical and numerical tests in the article. The R code used to obtain the maximum composite partial

Estimates of global prevalence of childhood underweight in 1990 and 2015.

PubMed

de Onis, Mercedes; Blössner, Monika; Borghi, Elaine; Frongillo, Edward A; Morris, Richard

2004-06-02

One key target of the United Nations Millennium Development goals is to reduce the prevalence of underweight among children younger than 5 years by half between 1990 and 2015. To estimate trends in childhood underweight by geographic regions of the world. Time series study of prevalence of underweight, defined as weight 2 SDs below the mean weight for age of the National Center for Health Statistics and World Health Organization (WHO) reference population. National prevalence rates derived from the WHO Global Database on Child Growth and Malnutrition, which includes data on approximately 31 million children younger than 5 years who participated in 419 national nutritional surveys in 139 countries from 1965 through 2002. Linear mixed-effects modeling was used to estimate prevalence rates and numbers of underweight children by region in 1990 and 2015 and to calculate the changes (ie, increase or decrease) to these values between 1990 and 2015. Worldwide, underweight prevalence was projected to decline from 26.5% in 1990 to 17.6% in 2015, a change of -34% (95% confidence interval [CI], -43% to -23%). In developed countries, the prevalence was estimated to decrease from 1.6% to 0.9%, a change of -41% (95% CI, -92% to 343%). In developing regions, the prevalence was forecasted to decline from 30.2% to 19.3%, a change of -36% (95% CI, -45% to -26%). In Africa, the prevalence of underweight was forecasted to increase from 24.0% to 26.8%, a change of 12% (95% CI, 8%-16%). In Asia, the prevalence was estimated to decrease from 35.1% to 18.5%, a change of -47% (95% CI, -58% to -34%). Worldwide, the number of underweight children was projected to decline from 163.8 million in 1990 to 113.4 million in 2015, a change of -31% (95% CI, -40% to -20%). Numbers are projected to decrease in all subregions except the subregions of sub-Saharan, Eastern, Middle, and Western Africa, which are expected to experience substantial increases in the number of underweight children. An overall

Use of Pathogen-Specific Antibody Biomarkers to Estimate Waterborne Infections in Population-Based Settings

PubMed Central

Exum, Natalie G.; Pisanic, Nora; Granger, Douglas A.; Schwab, Kellogg J.; Detrick, Barbara; Kosek, Margaret; Egorov, Andrey I.; Griffin, Shannon M.; Heaney, Christopher D.

2016-01-01

Purpose of review This review discusses the utility of pathogen-specific antibody biomarkers for improving estimates of the population burden of waterborne infections, assessing the fraction of infections that can be prevented by specific water treatments, and understanding transmission routes and the natural history and ecology of disease in different populations (including asymptomatic infection rates). Recent findings We review recent literature on the application of pathogen-specific antibody response data to estimate incidence and prevalence of acute infections and their utility to assess the contributions of waterborne transmission pathways. Advantages and technical challenges associated with the use of serum versus minimally invasive salivary antibody biomarkers in cross-sectional and prospective surveys are discussed. Summary We highlight recent advances and challenges and outline future directions for research, development, and application of antibody-based and other immunological biomarkers of waterborne infections. PMID:27352014

Spatially Interpolated Disease Prevalence Estimation Using Collateral Indicators of Morbidity and Ecological Risk

PubMed Central

Congdon, Peter

2013-01-01

This paper considers estimation of disease prevalence for small areas (neighbourhoods) when the available observations on prevalence are for an alternative partition of a region, such as service areas. Interpolation to neighbourhoods uses a kernel method extended to take account of two types of collateral information. The first is morbidity and service use data, such as hospital admissions, observed for neighbourhoods. Variations in morbidity and service use are expected to reflect prevalence. The second type of collateral information is ecological risk factors (e.g., pollution indices) that are expected to explain variability in prevalence in service areas, but are typically observed only for neighbourhoods. An application involves estimating neighbourhood asthma prevalence in a London health region involving 562 neighbourhoods and 189 service (primary care) areas. PMID:24129116

Spatially interpolated disease prevalence estimation using collateral indicators of morbidity and ecological risk.

PubMed

Congdon, Peter

2013-10-14

This paper considers estimation of disease prevalence for small areas (neighbourhoods) when the available observations on prevalence are for an alternative partition of a region, such as service areas. Interpolation to neighbourhoods uses a kernel method extended to take account of two types of collateral information. The first is morbidity and service use data, such as hospital admissions, observed for neighbourhoods. Variations in morbidity and service use are expected to reflect prevalence. The second type of collateral information is ecological risk factors (e.g., pollution indices) that are expected to explain variability in prevalence in service areas, but are typically observed only for neighbourhoods. An application involves estimating neighbourhood asthma prevalence in a London health region involving 562 neighbourhoods and 189 service (primary care) areas.

Prevalence of hepatitis C virus infection among high-risk groups in Iran: a systematic review and meta-analysis.

PubMed

Nematollahi, S; Ayubi, E; Almasi-Hashiani, A; Mansori, K; Moradi, Y; Veisani, Y; Jenabi, E; Gholamaliei, B; Khazaei, S

2018-06-20

Determination of the true burden of hepatitis C virus (HCV) infection among high-risk groups relies heavily on occurrence measures such as prevalence, which are vital for implementation of preventive action plans. Nevertheless, up-to-date data on the prevalence of HCV infection remain scarce in Iran. This study aimed to review the relevant literature systematically and determine the pooled prevalence of HCV infection among high-risk groups in Iran. Systematic review & meta-analysis. In 2016, electronic scientific databases including PubMed, Scopus, Web of Science and local databases were searched using a detailed search strategy with language restricted to English and Farsi. The reference lists of the studies included in this review were also screened. Data were reviewed and extracted independently by two authors. A random effects model was used to estimate the pooled prevalence. Sources of heterogeneity among the studies were determined using subgroup analysis and meta-regression. In total, 1817 records were identified in the initial search, and 46 records were included in the meta-analysis. The overall prevalence of HCV among high-risk groups was 32.3%. The prevalence was 41.3% in injection drug users (IDUs), 22.9% in prisoners, 16.2% in drug-dependent individuals and 24.6% in drug-dependent prisoners. Subgroup and meta-regression analyses revealed that geographical location and year of publication were the probable sources of heterogeneity. This meta-analysis found a high prevalence of HCV among high-risk groups in Iran, particularly among IDUs. There is a need for prevention strategies to reduce the burden of HCV infection among high-risk groups, particularly IDUs. Copyright © 2018 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Causes and prevalence of visual impairment among adults in the United States.

PubMed

Congdon, Nathan; O'Colmain, Benita; Klaver, Caroline C W; Klein, Ronald; Muñoz, Beatriz; Friedman, David S; Kempen, John; Taylor, Hugh R; Mitchell, Paul

2004-04-01

To estimate the cause-specific prevalence and distribution of blindness and low vision in the United States by age, race/ethnicity, and gender, and to estimate the change in these prevalence figures over the next 20 years. Summary prevalence estimates of blindness (both according to the US definition of < or =6/60 [< or =20/200] best-corrected visual acuity in the better-seeing eye and the World Health Organization standard of < 6/120 [< 20/400]) and low vision (< 6/12 [< 20/40] best-corrected vision in the better-seeing eye) were prepared separately for black, Hispanic, and white persons in 5-year age intervals starting at 40 years. The estimated prevalences were based on recent population-based studies in the United States, Australia, and Europe. These estimates were applied to 2000 US Census data, and to projected US population figures for 2020, to estimate the number of Americans with visual impairment. Cause-specific prevalences of blindness and low vision were also estimated for the different racial/ethnic groups. Based on demographics from the 2000 US Census, an estimated 937 000 (0.78%) Americans older than 40 years were blind (US definition). An additional 2.4 million Americans (1.98%) had low vision. The leading cause of blindness among white persons was age-related macular degeneration (54.4% of the cases), while among black persons, cataract and glaucoma accounted for more than 60% of blindness. Cataract was the leading cause of low vision, responsible for approximately 50% of bilateral vision worse than 6/12 (20/40) among white, black, and Hispanic persons. The number of blind persons in the US is projected to increase by 70% to 1.6 million by 2020, with a similar rise projected for low vision. Blindness or low vision affects approximately 1 in 28 Americans older than 40 years. The specific causes of visual impairment, and especially blindness, vary greatly by race/ethnicity. The prevalence of visual disabilities will increase markedly during the next

Estimation of HPV prevalence in young women in Scotland; monitoring of future vaccine impact

PubMed Central

2013-01-01

Background Estimation of pre-immunisation prevalence of HPV and distribution of HPV types is fundamental to understanding the subsequent impact of HPV vaccination. We describe the type specific prevalence of HPV in females aged 20–21 in Scotland who attended or defaulted from cervical screening using three specimen types; from attenders liquid based cytology and from defaulters urine or self-taken swabs. Methods Residual liquid based cytology samples (n = 2148), collected from women aged 20–21 attending for their first smear were genotyped for HPV. A sample (n = 709) from women who had defaulted from screening was also made available for HPV testing through the use of postal testing kits (either urine samples (n = 378) or self-taken swabs (n = 331)). Estimates of prevalence weighted by deprivation, and for the postal testing kit, also by reminder status and specimen type were calculated for each HPV type. The distribution of HPV types were compared between specimen types and the occurrence of multiple high-risk infections examined. The influence of demographic factors on high-risk HPV positivity and multiple infections was examined via logistic regression. Results The prevalence of any HPV in young women aged 20–21 was 32.2% for urine, 39.5% for self-taken swab, and 49.4% for LBC specimens. Infection with vaccine specific types (HPV 16, 18) or those associated with cross-protection (HPV 31, 33, 45, 51) was common. Individuals were more likely to test positive for high-risk HPV if they resided in an area of high deprivation or in a rural area. The overall distribution of HPV types did not vary between defaulters and attenders. Multiple infections occurred in 48.1% of high-risk HPV positive individuals. Excluding vaccine types the most common pairing was HPV 56 and 66. Conclusions Understanding of the pre-immunisation prevalence of HPV in young women puts Scotland in a prime position to assess the early effect of vaccination as the first highly

Estimation of HPV prevalence in young women in Scotland; monitoring of future vaccine impact.

PubMed

Kavanagh, Kimberley; Sinka, Katy; Cuschieri, Kate; Love, John; Potts, Alison; Pollock, Kevin G J; Cubie, Heather; Donaghy, Martin; Robertson, Chris

2013-11-05

Estimation of pre-immunisation prevalence of HPV and distribution of HPV types is fundamental to understanding the subsequent impact of HPV vaccination. We describe the type specific prevalence of HPV in females aged 20-21 in Scotland who attended or defaulted from cervical screening using three specimen types; from attenders liquid based cytology and from defaulters urine or self-taken swabs. Residual liquid based cytology samples (n = 2148), collected from women aged 20-21 attending for their first smear were genotyped for HPV. A sample (n = 709) from women who had defaulted from screening was also made available for HPV testing through the use of postal testing kits (either urine samples (n = 378) or self-taken swabs (n = 331)). Estimates of prevalence weighted by deprivation, and for the postal testing kit, also by reminder status and specimen type were calculated for each HPV type. The distribution of HPV types were compared between specimen types and the occurrence of multiple high-risk infections examined. The influence of demographic factors on high-risk HPV positivity and multiple infections was examined via logistic regression. The prevalence of any HPV in young women aged 20-21 was 32.2% for urine, 39.5% for self-taken swab, and 49.4% for LBC specimens. Infection with vaccine specific types (HPV 16, 18) or those associated with cross-protection (HPV 31, 33, 45, 51) was common. Individuals were more likely to test positive for high-risk HPV if they resided in an area of high deprivation or in a rural area. The overall distribution of HPV types did not vary between defaulters and attenders. Multiple infections occurred in 48.1% of high-risk HPV positive individuals. Excluding vaccine types the most common pairing was HPV 56 and 66. Understanding of the pre-immunisation prevalence of HPV in young women puts Scotland in a prime position to assess the early effect of vaccination as the first highly vaccinated cohorts of individuals enter the screening

Estimating Contraceptive Prevalence Using Logistics Data for Short-Acting Methods: Analysis Across 30 Countries.

PubMed

Cunningham, Marc; Bock, Ariella; Brown, Niquelle; Sacher, Suzy; Hatch, Benjamin; Inglis, Andrew; Aronovich, Dana

2015-09-01

Contraceptive prevalence rate (CPR) is a vital indicator used by country governments, international donors, and other stakeholders for measuring progress in family planning programs against country targets and global initiatives as well as for estimating health outcomes. Because of the need for more frequent CPR estimates than population-based surveys currently provide, alternative approaches for estimating CPRs are being explored, including using contraceptive logistics data. Using data from the Demographic and Health Surveys (DHS) in 30 countries, population data from the United States Census Bureau International Database, and logistics data from the Procurement Planning and Monitoring Report (PPMR) and the Pipeline Monitoring and Procurement Planning System (PipeLine), we developed and evaluated 3 models to generate country-level, public-sector contraceptive prevalence estimates for injectable contraceptives, oral contraceptives, and male condoms. Models included: direct estimation through existing couple-years of protection (CYP) conversion factors, bivariate linear regression, and multivariate linear regression. Model evaluation consisted of comparing the referent DHS prevalence rates for each short-acting method with the model-generated prevalence rate using multiple metrics, including mean absolute error and proportion of countries where the modeled prevalence rate for each method was within 1, 2, or 5 percentage points of the DHS referent value. For the methods studied, family planning use estimates from public-sector logistics data were correlated with those from the DHS, validating the quality and accuracy of current public-sector logistics data. Logistics data for oral and injectable contraceptives were significantly associated (P<.05) with the referent DHS values for both bivariate and multivariate models. For condoms, however, that association was only significant for the bivariate model. With the exception of the CYP-based model for condoms, models

Estimating Contraceptive Prevalence Using Logistics Data for Short-Acting Methods: Analysis Across 30 Countries

PubMed Central

Cunningham, Marc; Brown, Niquelle; Sacher, Suzy; Hatch, Benjamin; Inglis, Andrew; Aronovich, Dana

2015-01-01

Background: Contraceptive prevalence rate (CPR) is a vital indicator used by country governments, international donors, and other stakeholders for measuring progress in family planning programs against country targets and global initiatives as well as for estimating health outcomes. Because of the need for more frequent CPR estimates than population-based surveys currently provide, alternative approaches for estimating CPRs are being explored, including using contraceptive logistics data. Methods: Using data from the Demographic and Health Surveys (DHS) in 30 countries, population data from the United States Census Bureau International Database, and logistics data from the Procurement Planning and Monitoring Report (PPMR) and the Pipeline Monitoring and Procurement Planning System (PipeLine), we developed and evaluated 3 models to generate country-level, public-sector contraceptive prevalence estimates for injectable contraceptives, oral contraceptives, and male condoms. Models included: direct estimation through existing couple-years of protection (CYP) conversion factors, bivariate linear regression, and multivariate linear regression. Model evaluation consisted of comparing the referent DHS prevalence rates for each short-acting method with the model-generated prevalence rate using multiple metrics, including mean absolute error and proportion of countries where the modeled prevalence rate for each method was within 1, 2, or 5 percentage points of the DHS referent value. Results: For the methods studied, family planning use estimates from public-sector logistics data were correlated with those from the DHS, validating the quality and accuracy of current public-sector logistics data. Logistics data for oral and injectable contraceptives were significantly associated (P<.05) with the referent DHS values for both bivariate and multivariate models. For condoms, however, that association was only significant for the bivariate model. With the exception of the CYP

Prevalence estimates for primary brain tumors in the United States by age, gender, behavior, and histology.

PubMed

Porter, Kimberly R; McCarthy, Bridget J; Freels, Sally; Kim, Yoonsang; Davis, Faith G

2010-06-01

Prevalence is the best indicator of cancer survivorship in the population, but few studies have focused on brain tumor prevalence because of previous data limitations. Hence, the full impact of primary brain tumors on the healthcare system in the United States is not completely described. The present study provides an estimate of the prevalence of disease in the United States, updating an earlier prevalence study. Incidence data for 2004 and survival data for 1985-2005 were obtained by the Central Brain Tumor Registry of the United States from selected regions, modeled under 2 different survival assumptions, to estimate prevalence rates for the year 2004 and projected estimates for 2010. The overall incidence rate for primary brain tumors was 18.1 per 100 000 person-years with 2-, 5-, 10-, and 20-year observed survival rates of 62%, 54%, 45%, and 30%, respectively. On the basis of the sum of nonmalignant and averaged malignant estimates, the overall prevalence rate of individuals with a brain tumor was estimated to be 209.0 per 100 000 in 2004 and 221.8 per 100 000 in 2010. The female prevalence rate (264.8 per 100 000) was higher than that in males (158.7 per 100 000). The averaged prevalence rate for malignant tumors (42.5 per 100 000) was lower than the prevalence for nonmalignant tumors (166.5 per 100 000). This study provides estimates of the 2004 (n = 612 770) and 2010 (n = 688 096) expected number of individuals living with primary brain tumor diagnoses in the United States, providing more current and robust estimates for aiding healthcare planning and patient advocacy for an aging US population.

Prevalence of traumatic brain injury in incarcerated groups compared to the general population: a meta-analysis.

PubMed

Farrer, Thomas J; Hedges, Dawson W

2011-03-30

Traumatic brain injury can cause numerous behavioral abnormalities including aggression, violence, impulsivity, and apathy, factors that can be associated with criminal behavior and incarceration. To better characterize the association between traumatic brain injury and incarceration, we pooled reported frequencies of lifetime traumatic brain injury of any severity among incarcerated samples and compared the pooled frequency to estimates of the lifetime prevalence of traumatic brain injury in the general population. We found a significantly higher prevalence of traumatic brain injury in the incarcerated groups compared to the general population. As such, there appears to be an association between traumatic brain injury and incarceration. Copyright © 2011 Elsevier Inc. All rights reserved.

Republic of Georgia estimates for prevalence of drug use: Randomized response techniques suggest under-estimation.

PubMed

Kirtadze, Irma; Otiashvili, David; Tabatadze, Mzia; Vardanashvili, Irina; Sturua, Lela; Zabransky, Tomas; Anthony, James C

2018-06-01

Validity of responses in surveys is an important research concern, especially in emerging market economies where surveys in the general population are a novelty, and the level of social control is traditionally higher. The Randomized Response Technique (RRT) can be used as a check on response validity when the study aim is to estimate population prevalence of drug experiences and other socially sensitive and/or illegal behaviors. To apply RRT and to study potential under-reporting of drug use in a nation-scale, population-based general population survey of alcohol and other drug use. For this first-ever household survey on addictive substances for the Country of Georgia, we used the multi-stage probability sampling of 18-to-64-year-old household residents of 111 urban and 49 rural areas. During the interviewer-administered assessments, RRT involved pairing of sensitive and non-sensitive questions about drug experiences. Based upon the standard household self-report survey estimate, an estimated 17.3% [95% confidence interval, CI: 15.5%, 19.1%] of Georgian household residents have tried cannabis. The corresponding RRT estimate was 29.9% [95% CI: 24.9%, 34.9%]. The RRT estimates for other drugs such as heroin also were larger than the standard self-report estimates. We remain unsure about what is the "true" value for prevalence of using illegal psychotropic drugs in the Republic of Georgia study population. Our RRT results suggest that standard non-RRT approaches might produce 'under-estimates' or at best, highly conservative, lower-end estimates. Copyright © 2018 Elsevier B.V. All rights reserved.

Overall and income specific effect on prevalence of overweight and obesity of 20% sugar sweetened drink tax in UK: econometric and comparative risk assessment modelling study

PubMed Central

Briggs, Adam D M; Mytton, Oliver T; Kehlbacher, Ariane; Tiffin, Richard; Scarborough, Peter

2013-01-01

Objective To model the overall and income specific effect of a 20% tax on sugar sweetened drinks on the prevalence of overweight and obesity in the UK. Design Econometric and comparative risk assessment modelling study. Setting United Kingdom. Population Adults aged 16 and over. Intervention A 20% tax on sugar sweetened drinks. Main outcome measures The primary outcomes were the overall and income specific changes in the number and percentage of overweight (body mass index ≥25) and obese (≥30) adults in the UK following the implementation of the tax. Secondary outcomes were the effect by age group (16-29, 30-49, and ≥50 years) and by UK constituent country. The revenue generated from the tax and the income specific changes in weekly expenditure on drinks were also estimated. Results A 20% tax on sugar sweetened drinks was estimated to reduce the number of obese adults in the UK by 1.3% (95% credible interval 0.8% to 1.7%) or 180 000 (110 000 to 247 000) people and the number who are overweight by 0.9% (0.6% to 1.1%) or 285 000 (201 000 to 364 000) people. The predicted reductions in prevalence of obesity for income thirds 1 (lowest income), 2, and 3 (highest income) were 1.3% (0.3% to 2.0%), 0.9% (0.1% to 1.6%), and 2.1% (1.3% to 2.9%). The effect on obesity declined with age. Predicted annual revenue was £276m (£272m to £279m), with estimated increases in total expenditure on drinks for income thirds 1, 2, and 3 of 2.1% (1.4% to 3.0%), 1.7% (1.2% to 2.2%), and 0.8% (0.4% to 1.2%). Conclusions A 20% tax on sugar sweetened drinks would lead to a reduction in the prevalence of obesity in the UK of 1.3% (around 180 000 people). The greatest effects may occur in young people, with no significant differences between income groups. Both effects warrant further exploration. Taxation of sugar sweetened drinks is a promising population measure to target population obesity, particularly among younger adults. PMID:24179043

Overall and income specific effect on prevalence of overweight and obesity of 20% sugar sweetened drink tax in UK: econometric and comparative risk assessment modelling study.

PubMed

Briggs, Adam D M; Mytton, Oliver T; Kehlbacher, Ariane; Tiffin, Richard; Rayner, Mike; Scarborough, Peter

2013-10-31

To model the overall and income specific effect of a 20% tax on sugar sweetened drinks on the prevalence of overweight and obesity in the UK. Econometric and comparative risk assessment modelling study. United Kingdom. Adults aged 16 and over. A 20% tax on sugar sweetened drinks. The primary outcomes were the overall and income specific changes in the number and percentage of overweight (body mass index ≥ 25) and obese (≥ 30) adults in the UK following the implementation of the tax. Secondary outcomes were the effect by age group (16-29, 30-49, and ≥ 50 years) and by UK constituent country. The revenue generated from the tax and the income specific changes in weekly expenditure on drinks were also estimated. A 20% tax on sugar sweetened drinks was estimated to reduce the number of obese adults in the UK by 1.3% (95% credible interval 0.8% to 1.7%) or 180,000 (110,000 to 247,000) people and the number who are overweight by 0.9% (0.6% to 1.1%) or 285,000 (201,000 to 364,000) people. The predicted reductions in prevalence of obesity for income thirds 1 (lowest income), 2, and 3 (highest income) were 1.3% (0.3% to 2.0%), 0.9% (0.1% to 1.6%), and 2.1% (1.3% to 2.9%). The effect on obesity declined with age. Predicted annual revenue was £276m (£272m to £279m), with estimated increases in total expenditure on drinks for income thirds 1, 2, and 3 of 2.1% (1.4% to 3.0%), 1.7% (1.2% to 2.2%), and 0.8% (0.4% to 1.2%). A 20% tax on sugar sweetened drinks would lead to a reduction in the prevalence of obesity in the UK of 1.3% (around 180,000 people). The greatest effects may occur in young people, with no significant differences between income groups. Both effects warrant further exploration. Taxation of sugar sweetened drinks is a promising population measure to target population obesity, particularly among younger adults.

Overview of Celiac Disease in Russia: Regional Data and Estimated Prevalence

PubMed Central

Erdes, Svetlana I.; Antishin, Anton S.

2017-01-01

Celiac disease (CD) is an autoimmune enteropathy triggered by the ingestion of dietary gluten from some cereals mainly in individuals carrying the HLA-DQ2 and/or HLA-DQ8 haplotypes. As an autoimmune disease, CD is manifested in the small intestine in the form of a progressive and reversible inflammatory lesion due to immune response to self-antigens. Indeed, CD is one of the most challenging medicosocial problems in current gastroenterology. At present, the global CD prevalence is estimated at approximately 1% based on data sent from different locations and available CD screening strategies used. However, it is impossible to estimate global CD prevalence without all the data from the world, including Russia. In this review, we summarize the data on the incidence and prevalence of CD across geographically distinct regions of Russia, which are mostly present in local Russian scientific sources. Our conclusion is that the situation of CD prevalence in Russia is higher than is commonly believed and follows global tendencies that correspond to the epidemiologic situation in Europe, America, and Southwest Asia. PMID:28316996

Overview of Celiac Disease in Russia: Regional Data and Estimated Prevalence.

PubMed

Savvateeva, Lyudmila V; Erdes, Svetlana I; Antishin, Anton S; Zamyatnin, Andrey A

2017-01-01

Celiac disease (CD) is an autoimmune enteropathy triggered by the ingestion of dietary gluten from some cereals mainly in individuals carrying the HLA-DQ2 and/or HLA-DQ8 haplotypes. As an autoimmune disease, CD is manifested in the small intestine in the form of a progressive and reversible inflammatory lesion due to immune response to self-antigens. Indeed, CD is one of the most challenging medicosocial problems in current gastroenterology. At present, the global CD prevalence is estimated at approximately 1% based on data sent from different locations and available CD screening strategies used. However, it is impossible to estimate global CD prevalence without all the data from the world, including Russia. In this review, we summarize the data on the incidence and prevalence of CD across geographically distinct regions of Russia, which are mostly present in local Russian scientific sources. Our conclusion is that the situation of CD prevalence in Russia is higher than is commonly believed and follows global tendencies that correspond to the epidemiologic situation in Europe, America, and Southwest Asia.

The prevalence of stuttering, voice, and speech-sound disorders in primary school students in Australia.

PubMed

McKinnon, David H; McLeod, Sharynne; Reilly, Sheena

2007-01-01

The aims of this study were threefold: to report teachers' estimates of the prevalence of speech disorders (specifically, stuttering, voice, and speech-sound disorders); to consider correspondence between the prevalence of speech disorders and gender, grade level, and socioeconomic status; and to describe the level of support provided to schoolchildren with speech disorders. Students with speech disorders were identified from 10,425 students in Australia using a 4-stage process: training in the data collection process, teacher identification, confirmation by a speech-language pathologist, and consultation with district special needs advisors. The prevalence of students with speech disorders was estimated; specifically, 0.33% of students were identified as stuttering, 0.12% as having a voice disorder, and 1.06% as having a speech-sound disorder. There was a higher prevalence of speech disorders in males than in females. As grade level increased, the prevalence of speech disorders decreased. There was no significant difference in the pattern of prevalence across the three speech disorders and four socioeconomic groups; however, students who were identified with a speech disorder were more likely to be in the higher socioeconomic groups. Finally, there was a difference between the perceived and actual level of support that was provided to these students. These prevalence figures are lower than those using initial identification by speech-language pathologists and similar to those using parent report.

The Problem of Rarity: Estimation of Prevalence in Rare Disease.

PubMed

Auvin, Stéphane; Irwin, John; Abi-Aad, Paul; Battersby, Alysia

2018-05-01

From a disease's first description to its wider recognition, factors such as changes over time in diagnostic criteria, available therapies, and subsequent mortality rates may influence diagnosed prevalence of rare diseases. To propose a novel methodology for estimating the true prevalence of rare diseases using current incidence adjusted to changing diagnostic practice over time. This article focuses on rare diseases whose diagnosis may have changed over time, and raises the hypothesis that prevalence calculated from current incidence may be higher than diagnosed prevalence, which may lag behind the current disease definition and diagnostic methods. A rare epileptic encephalopathy, Dravet syndrome (DS), is explored as an illustrative example. A targeted literature review was performed for DS to identify all reported incidence, prevalence, and mortality and depict how diagnostic practice has evolved over time. A conceptual model was developed to calculate prevalence derived from current incidence figures alone (incidence-derived prevalence) or incidence adjusted with factors that cause a diagnostic drag (diagnostic awareness-adjusted prevalence). We identified sufficient publications of incidence and prevalence to test the conceptual model. For pediatric patients with DS, diagnosed prevalence in the field (as reported in current literature) matches incidence-derived prevalence, whereas for adult patients, it is overestimated by incidence-derived prevalence, but not by diagnostic awareness-adjusted prevalence. Care should be taken with current incidence-derived prevalence figures to not overstate the prevalence in rare diseases, as methodological challenges in counting small populations, coupled with advances in rare disease discovery, may cause discrepancies. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Lifetime and 12-month prevalence estimates for mental disorders in northeastern Germany: findings from the Study of Health in Pomerania.

PubMed

Asselmann, E; Beesdo-Baum, K; Hamm, A; Schmidt, C O; Hertel, J; Grabe, H J; Pané-Farré, C A

2018-06-15

Few epidemiological studies presented 12-month and lifetime prevalence estimates for DSM-IV mental disorders in the adult general population by sex and age up to very old age. From 2007 to 2010, DSM-IV mental disorders were assessed with the DIA-X/M-CIDI among N = 2400 participants (aged 29-89 years) from the Study of Health in Pomerania, an epidemiological study based on a two-stage stratified cluster sample randomly drawn from the adult general population in northeastern Germany. 36.3% of the sample was affected by any 12-month and 54.8% by any lifetime mental disorder. The most frequent diagnostic groups were anxiety (12-month: 14.8%, lifetime: 23.4%), substance use (12-month: 14.5%, lifetime: 25.0%), somatoform (12-month: 12.9%, lifetime: 20.4%) and depressive (12-month: 7.3%, lifetime: 18.6%) disorders. Except for substance use (higher prevalence in men) and bipolar disorders (comparable prevalence in men and women), higher 12-month and lifetime prevalence estimates were found in women vs. men. Moreover, lower 12-month and lifetime prevalence estimates were found in older (aged 60-74 or 75-89 years) vs. younger (aged 29-44 or 45-59 years) age groups. 22.6% (men: 21.1%, women: 23.9%) of those affected by any 12-month disorder met criteria for two and 13.6% (men: 9.6%, women: 16.9%) for three or more 12-month diagnoses. Similarly, 26.4% (men: 25.7%, women: 26.9%) of those affected by any lifetime disorder met criteria for two and 22.7% (men: 19.6%, women: 25.2%) for three or more lifetime diagnoses. Our findings demonstrate the frequency of mental disorders in northeastern Germany and emphasize the need for continued prevention and intervention efforts.

Smoking and smokeless tobacco use in nine South and Southeast Asian countries: prevalence estimates and social determinants from Demographic and Health Surveys.

PubMed

Sreeramareddy, Chandrashekhar T; Pradhan, Pranil Man Singh; Mir, Imtiyaz Ali; Sin, Shwe

2014-01-01

In South and Southeast Asian countries, tobacco is consumed in diverse forms, and smoking among women is very low. We aimed to provide national estimates of prevalence and social determinants of smoking and smokeless tobacco use among men and women separately. Data from Demographic and Health Surveys completed in nine countries (India, Pakistan, Nepal, Bangladesh, Maldives, Philippines, Cambodia, Indonesia, and Timor Leste) were analyzed. Current smoking or smokeless tobacco use was assessed as response "yes" to one or more of three questions, such as "Do you currently smoke cigarettes?" Weighted country-level prevalence rates for socio-economic subgroups were calculated for smoking and smokeless tobacco use. Binary logistic regression analyses were done on STATA/IC (version 10) by 'svy' command. Prevalence and type of tobacco use among men and women varied across the countries and among socio-economic sub groups. Smoking prevalence was much lower in women than men in all countries. Smoking among men was very high in Indonesia, Maldives, and Bangladesh. Smokeless tobacco (mainly chewable) was used in diverse forms, particularly in India, among both men and women. Chewing tobacco was common in Nepal, Bangladesh, Maldives, and Cambodia. Both smoking and smokeless tobacco use were associated with higher age, lower education, and poverty, but their association with place of residence and marital status was not uniform between men and women across the countries. Policymakers should consider type of tobacco consumption and their differentials among various population subgroups to implement country-specific tobacco control policies and target the vulnerable groups. Smokeless tobacco use should also be prioritized in tobacco control efforts.

On the influence of latency estimation on dynamic group communication using overlays

NASA Astrophysics Data System (ADS)

Vik, Knut-Helge; Griwodz, Carsten; Halvorsen, Pål

2009-01-01

Distributed interactive applications tend to have stringent latency requirements and some may have high bandwidth demands. Many of them have also very dynamic user groups for which all-to-all communication is needed. In online multiplayer games, for example, such groups are determined through region-of-interest management in the application. We have investigated a variety of group management approaches for overlay networks in earlier work and shown that several useful tree heuristics exist. However, these heuristics require full knowledge of all overlay link latencies. Since this is not scalable, we investigate the effects that latency estimation techqniues have ton the quality of overlay tree constructions. We do this by evaluating one example of our group management approaches in Planetlab and examing how latency estimation techqniues influence their quality. Specifically, we investigate how two well-known latency estimation techniques, Vivaldi and Netvigator, affect the quality of tree building.

Prevalence of diabetes across different immigrant groups in North-eastern Italy.

PubMed

Fedeli, U; Casotto, V; Ferroni, E; Saugo, M; Targher, G; Zoppini, G

2015-10-01

Type 2 diabetes, one of the most important non-communicable diseases, represents a major health problem worldwide. Immigrants may contribute relevantly to the increase in diabetes. The aim of the study was to investigate variability in diabetes prevalence across different immigrant groups in the Veneto Region (northeastern Italy). Diabetic subjects on January 2013 were identified by record linkage of hospital discharge records, drug prescriptions, and exemptions from medical charges for diabetes. Immigrant groups were identified based on citizenship. Age-standardized prevalence rates were obtained for residents aged 20-59 years by the direct method, taking the whole regional population as reference. Prevalence rate ratios (RR) with 95% Confidence Intervals (CI) were computed with respect to Italian citizens. Among residents aged 20-59 years, 45280 Italian and 7782 foreign subjects affected by diabetes were identified. Prevalence rates were highest among immigrants from South-East Asia, RR 4.9 (CI 4.7-5.1) among males, and 7.6 (7.2-8.1) among females, followed by residents from both North and Sub-Saharan Africa. Citizens from Eastern Europe (the largest immigrant group) showed rates similar to Italians. Most South-Asian patients aged 20-39 years were not insulin-treated, suggesting a very high risk of early onset type 2 diabetes in this ethnic group. Large variations in diabetes prevalence by ethnicity should prompt tailored strategies for primary prevention, diabetes screening, and disease control. An increased demand for prevention and health care in selected population groups should guide appropriate resource allocation. Copyright © 2015 Elsevier B.V. All rights reserved.

Prevalence estimates of combat-related post-traumatic stress disorder: critical review.

PubMed

Richardson, Lisa K; Frueh, B Christopher; Acierno, Ronald

2010-01-01

The aim of the present study was to provide a critical review of prevalence estimates of combat-related post-traumatic stress disorder (PTSD) among military personnel and veterans, and of the relevant factors that may account for the variability of estimates within and across cohorts, including methodological and conceptual factors accounting for differences in prevalence rates across nations, conflicts/wars, and studies. MEDLINE and PsycINFO databases were examined for literature on combat-related PTSD. The following terms were used independently and in combinations in this search: PTSD, combat, veterans, military, epidemiology, prevalence. The point prevalence of combat-related PTSD in US military veterans since the Vietnam War ranged from approximately 2% to 17%. Studies of recent conflicts suggest that combat-related PTSD afflicts between 4% and 17% of US Iraq War veterans, but only 3-6% of returning UK Iraq War veterans. Thus, the prevalence range is narrower and tends to have a lower ceiling among combat veterans of non-US Western nations. Variability in prevalence is likely due to differences in sampling strategies; measurement strategies; inclusion and measurement of the DSM-IV clinically significant impairment criterion; timing and latency of assessment and potential for recall bias; and combat experiences. Prevalence rates are also likely affected by issues related to PTSD course, chronicity, and comorbidity; symptom overlap with other psychiatric disorders; and sociopolitical and cultural factors that may vary over time and by nation. The disorder represents a significant and costly illness to veterans, their families, and society as a whole. Further carefully conceptualized research, however, is needed to advance our understanding of disorder prevalence, as well as associated information on course, phenomenology, protective factors, treatment, and economic costs.

Interpreting ambiguous ‘trace’ results in Schistosoma mansoni CCA Tests: Estimating sensitivity and specificity of ambiguous results with no gold standard

PubMed Central

Donnelly, Christl A.; Fenwick, Alan; Kabatereine, Narcis B.; Knowles, Sarah C. L.; Meité, Aboulaye; N'Goran, Eliézer K.; Nalule, Yolisa; Nogaro, Sarah; Phillips, Anna E.; Tukahebwa, Edridah Muheki; Fleming, Fiona M.

2017-01-01

Background The development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous ‘trace’ result between ‘positive’ and ‘negative’, and much debate has focused on interpretation of traces results. Methodology/Principle findings We show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both Côte d’Ivoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population. Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries. Conclusions Incorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence. PMID:29220354

Prevalence of antibodies to Chlamydia trachomatis in healthy population groups in Manitoba.

PubMed Central

Kordová, N.; Wilt, J. C.; Sekla, L.; Hannan, C.; Williams, T. W.; Stackiw, W.; Herchl, R.; Feltham, S.

1983-01-01

The prevalence of antibodies to Chlamydia trachomatis was determined in 1877 serum samples from healthy population groups of Caucasians, native Indians and recent Vietnamese immigrants in Manitoba. Testing was done with a commercially available immunofluorescence kit containing C. trachomatis antigen. The presence of antibodies was age-related; a progressive increase in prevalence was observed in children aged 1 to 15 years, and the overall prevalence was higher in female Caucasian blood donors and female Vietnamese immigrants than in males in both groups. However, there was no sex-related difference in prevalence among the subjects undergoing premarital testing or among the native Indians. Antibodies were more prevalent (p less than 0.001) in pregnant than in nonpregnant women matched for race and age, and a relatively high prevalence (66.6%) was found in the cord serum of newborns. The overall prevalence rate of antibodies in all Manitobans was 48.8% (44.9% in men, 55.9% in women and 35.3% in children. PMID:6627171

Estimating the prevalence of heterozygous familial hypercholesterolaemia: a systematic review and meta-analysis

PubMed Central

Akioyamen, Leo E; Genest, Jacques; Shan, Shubham D; Reel, Rachel L; Albaum, Jordan M; Chu, Anna; Tu, Jack V

2017-01-01

Objectives Heterozygous familial hypercholesterolaemia (FH) confers a significant risk for premature cardiovascular disease (CVD). However, the estimated prevalence of FH varies substantially among studies. We aimed to provide a summary estimate of FH prevalence in the general population and assess variations in frequency across different sociodemographic characteristics. Setting, participants and outcome measures We searched MEDLINE, EMBASE, Global Health, the Cochrane Library, PsycINFO and PubMed for peer-reviewed literature using validated strategies. Results were limited to studies published in English between January 1990 and January 2017. Studies were eligible if they determined FH prevalence using clinical criteria or DNA-based analyses. We determined a pooled point prevalence of FH in adults and children and assessed the variation of the pooled frequency by age, sex, geographical location, diagnostic method, study quality and year of publication. Estimates were pooled using random-effects meta-analysis. Differences by study-level characteristics were investigated through subgroups, meta-regression and sensitivity analyses. Results The pooled prevalence of FH from 19 studies including 2 458 456 unique individuals was 0.40% (95% CI 0.29% to 0.52%) which corresponds to a frequency of 1 in 250 individuals. FH prevalence was found to vary by age and geographical location but not by any other covariates. Results were consistent in sensitivity analyses. Conclusions Our systematic review suggests that FH is a common disorder, affecting 1 in 250 individuals. These findings underscore the need for early detection and management to decrease CVD risk. PMID:28864697

Endoparasite prevalence and recurrence across different age groups of dogs and cats

PubMed Central

Gates, Maureen C.; Nolan, Thomas J.

2009-01-01

The apparent prevalence of endoparasite infections across different age groups was calculated from 6,555 dogs and 1,566 cats that had a fecal examination performed upon presentation to the Veterinary Hospital of the University of Pennsylvania between 1997 and 2007. Based on notations from the medical history indicating prior parasite infections, estimates of recurrence were generated for each common group of parasites, including Trichuris, Giardia, ascarids, hookworms, Cystoisospora, and tapeworms. Endoparasitism was predominantly a disease of younger animals, with peak prevalence observed almost uniformly in dogs under 6 months old, with the exception of Trichuris with its longer pre-patent period, and in cats less than 18 months old. Furthermore, nearly 50% of dogs under 6 months old with a history of parasites, were diagnosed with at least one species of parasite on subsequent fecal examination. The percentage dropped to 18.4% in animals aged 1 – 4 years, but again increased to 31.5% in animals over 10 years old. There was no reported recurrence of Giardia or Cystoisospora from canine or feline patients older than 1 year. The recurrence of whipworm rose steadily with age, while hookworm and roundworm recurrence peaked in patients 1 - 4 years old. Findings from the study emphasize the importance of follow up fecal examinations and treatments in patients diagnosed with endoparasites. PMID:19709815

Prevalence of diabetic retinopathy in various ethnic groups: a worldwide perspective.

PubMed

Sivaprasad, Sobha; Gupta, Bhaskar; Crosby-Nwaobi, Roxanne; Evans, Jennifer

2012-01-01

The alarming rise in diabetes prevalence is a global public health and economic problem. Diabetic retinopathy is the most common complication of diabetes and the leading cause of blindness among working-age populations in the Western world. Screening and prompt treatment of diabetic retinopathy are not top priorities in many regions of the world, because the impacts of other causes of preventable blindness remain an issue. Ethnicity is a complex, independent risk factor for diabetic retinopathy. Observations from white populations cannot be extrapolated fully to other ethnic groups. The prevalence of diabetic retinopathy, sight-threatening diabetic retinopathy, and clinically significant macular edema are higher in people of South Asian, African, Latin American, and indigenous tribal descent compared to the white population. Although all ethnic groups are susceptible to the established risk factors of diabetic retinopathy-such as length of exposure and severity of hyperglycemia, hypertension, and hyperlipidemia-ethnic-specific risk factors also may influence these rates. Such risk factors may include differential susceptibility to conventional risk factors, insulin resistance, differences in anthropometric measurements, truncal obesity, urbanization, variations in access to healthcare systems, genetic susceptibility, and epigenetics. The rates of nonproliferative diabetic retinopathy appear to be declining in the United States, supporting the observation that better medical management of diabetes and prompt treatment of sight-threatening diabetic retinopathy substantially improve the long-term diabetic retinopathy incidence; studies from other parts of the world are limited and do not mirror this finding, however. We examine the ethnicity and region-based prevalence of diabetic retinopathy around the world and highlight the need to reinforce ethnicity-based screening and treatment thresholds in diabetic retinopathy. Copyright © 2012 Elsevier Inc. All rights

Prevalence of Gingivitis in a Group of 35- to 70-Year-Olds Residing in Puerto Rico.

PubMed

Elías-Boneta, Augusto R; Encarnación, Angeliz; Rivas-Tumanyan, Sona; Berríos-Ouslán, Beatriz C; García-Godoy, Bayardo; Murillo, Margarita; Diaz-Nicolas, Jomar; Lugo, Ferdinand; Toro, Milagros J

2017-09-01

Gingivitis, an inflammation of the gingival tissues, typically progresses to periodontitis. The objective of this study is to estimate the prevalence of gingivitis in 35- to 70-year-olds residing in San Juan, Puerto Rico, and assess the differences in gingivitis distribution between age and gender groups. A cross-sectional epidemiological study was conducted with a sample of patients from a private practice and patients/employees of the Puerto Rico Medical Center. Participants completed a medical history questionnaire and received soft/hard tissue and gingival assessments based on a modified Löe-Silness index. Descriptive statistics were employed to estimate the overall gingivitis prevalence, severity (mild, moderate, severe), and mean gingival index (GI). Bleeding on probing (BOP) prevalence and the mean percentage of BOP sites were calculated by gender and age. Multinomial logistic regression was used to evaluate the associations between age, gender, and severity in 3 categories; multivariate logistic regression was used for having >=40% sites with BOP (vs. having <40% sites with BOP as reference). Odds ratios were also estimated. All 300 participants (52% women; 48% men) had gingivitis. The mean GI was 1.38. Moderate gingivitis was detected in 83% of the participants, mild in 7.3%, and severe in 9.3%. BOP was observed in 99% of the subjects (mean % BOP sites = 34%). After adjusting for age, men had significantly higher odds of moderate (OR = 4.66) and severe gingivitis (OR =10.06), compared to women, as well as 1.76 times higher odds of having 40% or more sites with BOP. Gingivitis was observed in all participants. Men had significantly higher GI, compared to women. The prevalence of gingivitis was higher in Puerto Rico than in the US.

Estimated prevalence of hearing loss and provision of hearing services in Pacific Island nations.

PubMed

Sanders, Michael; Houghton, Natasha; Dewes, Ofa; McCool, Judith; Thorne, Peter R

2015-03-01

Hearing impairment (HI) affects an estimated 538 million people worldwide, with 80% of these living in developing countries. Untreated HI in childhood may lead to developmental delay and in adults results in social isolation, inability to find or maintain employment, and dependency. Early intervention and support programmes can significantly reduce the negative effects of HI. To estimate HI prevalence and identify available hearing services in some Pacific countries - Cook Islands, Fiji, Niue, Samoa, Tokelau, Tonga. Data were collected through literature review and correspondence with service providers. Prevalence estimates were based on census data and previously published regional estimates. Estimates indicate 20-23% of the population may have at least a mild HI, with up to 11% having a moderate impairment or worse. Estimated incidence of chronic otitis media in Pacific Island nations is 3-5 times greater than other Australasian countries in children under 10 years old. Permanent HI from otitis media is substantially more likely in children and adults in Pacific Island nations. Several organisations and individuals provide some limited hearing services in a few Pacific Island nations, but the majority of people with HI are largely underserved. Although accurate information on HI prevalence is lacking, prevalence estimates of HI and ear disease suggest they are significant health conditions in Pacific Island nations. There is relatively little support for people with HI or ear disease in the Pacific region. An investment in initiatives to both identify and support people with hearing loss in the Pacific is necessary.

Prevalence of Individuals Experiencing the Effects of Stroke in Canada: Trends and Projections.

PubMed

Krueger, Hans; Koot, Jacqueline; Hall, Ruth E; O'Callaghan, Christina; Bayley, Mark; Corbett, Dale

2015-08-01

Previous estimates of the number and prevalence of individuals experiencing the effects of stroke in Canada are out of date and exclude critical population groups. It is essential to have complete data that report on stroke disability for monitoring and planning purposes. The objective was to provide an updated estimate of the number of individuals experiencing the effects of stroke in Canada (and its regions), trending since 2000 and forecasted prevalence to 2038. The prevalence, trends, and projected number of individuals experiencing the effects of stroke were estimated using region-specific survey data and adjusted to account for children aged <12 years and individuals living in homes for the aged. In 2013, we estimate that there were 405 000 individuals experiencing the effects of stroke in Canada, yielding a prevalence of 1.15%. This value is expected to increase to between 654 000 and 726 000 by 2038. Trends in stroke data between 2000 and 2012 suggest a nonsignificant decrease in stroke prevalence, but a substantial and rising increase in the number of individuals experiencing the effects of stroke. Stroke prevalence varied considerably between regions. Previous estimates of stroke prevalence have underestimated the true number of individuals experiencing the effects of stroke in Canada. Furthermore, the projected increases that will result from population growth and demographic changes highlight the importance of maintaining up-to-date estimates. © 2015 American Heart Association, Inc.

The prevalence of food allergy: a meta-analysis.

PubMed

Rona, Roberto J; Keil, Thomas; Summers, Colin; Gislason, David; Zuidmeer, Laurian; Sodergren, Eva; Sigurdardottir, Sigurveig T; Lindner, Titia; Goldhahn, Klaus; Dahlstrom, Jorgen; McBride, Doreen; Madsen, Charlotte

2007-09-01

There is uncertainty about the prevalence of food allergy in communities. To assess the prevalence of food allergy by performing a meta-analysis according to the method of assessment used. The foods assessed were cow's milk, hen's egg, peanut, fish, shellfish, and an overall estimate of food allergy. We summarized the information in 5 categories: self-reported symptoms, specific IgE positive, specific skin prick test positive, symptoms combined with sensitization, and food challenge studies. We systematically searched MEDLINE and EMBASE for publications since 1990. The meta-analysis included only original studies. They were stratified by age groups: infant/preschool, school children, and adults. A total of 934 articles were identified, but only 51 were considered appropriate for inclusion. The prevalence of self-reported food allergy was very high compared with objective measures. There was marked heterogeneity between studies regardless of type of assessment or food item considered, and in most analyses this persisted after age stratification. Self-reported prevalence of food allergy varied from 1.2% to 17% for milk, 0.2% to 7% for egg, 0% to 2% for peanuts and fish, 0% to 10% for shellfish, and 3% to 35% for any food. There is a marked heterogeneity in the prevalence of food allergy that could be a result of differences in study design or methodology, or differences between populations. We recommend that measurements be made by using standardized methods, if possible food challenge. We need to be cautious in estimates of prevalence based only on self-reported food allergy.

Adult current smoking: differences in definitions and prevalence estimates--NHIS and NSDUH, 2008.

PubMed

Ryan, Heather; Trosclair, Angela; Gfroerer, Joe

2012-01-01

To compare prevalence estimates and assess issues related to the measurement of adult cigarette smoking in the National Health Interview Survey (NHIS) and the National Survey on Drug Use and Health (NSDUH). 2008 data on current cigarette smoking and current daily cigarette smoking among adults ≥18 years were compared. The standard NHIS current smoking definition, which screens for lifetime smoking ≥100 cigarettes, was used. For NSDUH, both the standard current smoking definition, which does not screen, and a modified definition applying the NHIS current smoking definition (i.e., with screen) were used. NSDUH consistently yielded higher current cigarette smoking estimates than NHIS and lower daily smoking estimates. However, with use of the modified NSDUH current smoking definition, a notable number of subpopulation estimates became comparable between surveys. Younger adults and racial/ethnic minorities were most impacted by the lifetime smoking screen, with Hispanics being the most sensitive to differences in smoking variable definitions among all subgroups. Differences in current cigarette smoking definitions appear to have a greater impact on smoking estimates in some sub-populations than others. Survey mode differences may also limit intersurvey comparisons and trend analyses. Investigators are cautioned to use data most appropriate for their specific research questions.

Estimated numbers of men and women infected with HIV/AIDS in Tijuana, Mexico.

PubMed

Brouwer, Kimberly C; Strathdee, Steffanie A; Magis-Rodríguez, Carlos; Bravo-García, Enrique; Gayet, Cecilia; Patterson, Thomas L; Bertozzi, Stefano M; Hogg, Robert S

2006-03-01

Tijuana, Mexico, just south of San Diego, California, is located by the busiest land border crossing in the world. Although UNAIDS considers Mexico to be a country of "low prevalence, high risk," recent surveillance data among sentinel populations in Tijuana suggests HIV prevalence is increasing. The aim of this study was to estimate the number of men and women aged 15 to 49 years infected with HIV in Tijuana. Gender and age-specific estimates of the Tijuana population were obtained from the 2000 Mexican census. Population and HIV prevalence estimates for at-risk groups were obtained from published reports, community based studies, and data from the Centro Nacional para la Prevención y Control del VIH/SIDA (CENSIDA). Age-specific fertility rates for Mexico were used to derive the number of low and high-risk pregnant women. Numbers of HIV-positive men and women were estimated for each at-risk group and then aggregated. A high growth scenario based on current HIV prevalence and a conservative, low growth estimate were determined. A total of 686,600 men and women in Tijuana were aged 15 to 49 years at the time of the 2000 census. Considering both scenarios, the number of infected persons ranged from 1,803 to 5,472 (HIV prevalence: 0.26 to 0.80%). The majority of these persons were men (>70%). The largest number of infected persons were MSM (N = 1,146 to 3,300) and IDUs (N = 147 to 650). Our data suggest that up to one in every 125 persons aged 15-49 years in Tijuana is HIV-infected. Interventions to reduce ongoing spread of HIV are urgently needed.

Estimating prevalence of coronary heart disease for small areas using collateral indicators of morbidity.

PubMed

Congdon, Peter

2010-01-01

Different indicators of morbidity for chronic disease may not necessarily be available at a disaggregated spatial scale (e.g., for small areas with populations under 10 thousand). Instead certain indicators may only be available at a more highly aggregated spatial scale; for example, deaths may be recorded for small areas, but disease prevalence only at a considerably higher spatial scale. Nevertheless prevalence estimates at small area level are important for assessing health need. An instance is provided by England where deaths and hospital admissions for coronary heart disease are available for small areas known as wards, but prevalence is only available for relatively large health authority areas. To estimate CHD prevalence at small area level in such a situation, a shared random effect method is proposed that pools information regarding spatial morbidity contrasts over different indicators (deaths, hospitalizations, prevalence). The shared random effect approach also incorporates differences between small areas in known risk factors (e.g., income, ethnic structure). A Poisson-multinomial equivalence may be used to ensure small area prevalence estimates sum to the known higher area total. An illustration is provided by data for London using hospital admissions and CHD deaths at ward level, together with CHD prevalence totals for considerably larger local health authority areas. The shared random effect involved a spatially correlated common factor, that accounts for clustering in latent risk factors, and also provides a summary measure of small area CHD morbidity.

Estimating Prevalence of Coronary Heart Disease for Small Areas Using Collateral Indicators of Morbidity

PubMed Central

Congdon, Peter

2010-01-01

Different indicators of morbidity for chronic disease may not necessarily be available at a disaggregated spatial scale (e.g., for small areas with populations under 10 thousand). Instead certain indicators may only be available at a more highly aggregated spatial scale; for example, deaths may be recorded for small areas, but disease prevalence only at a considerably higher spatial scale. Nevertheless prevalence estimates at small area level are important for assessing health need. An instance is provided by England where deaths and hospital admissions for coronary heart disease are available for small areas known as wards, but prevalence is only available for relatively large health authority areas. To estimate CHD prevalence at small area level in such a situation, a shared random effect method is proposed that pools information regarding spatial morbidity contrasts over different indicators (deaths, hospitalizations, prevalence). The shared random effect approach also incorporates differences between small areas in known risk factors (e.g., income, ethnic structure). A Poisson-multinomial equivalence may be used to ensure small area prevalence estimates sum to the known higher area total. An illustration is provided by data for London using hospital admissions and CHD deaths at ward level, together with CHD prevalence totals for considerably larger local health authority areas. The shared random effect involved a spatially correlated common factor, that accounts for clustering in latent risk factors, and also provides a summary measure of small area CHD morbidity. PMID:20195439

Estimated prevalence and incidence of diagnosed ADHD and health care utilization in adults in Sweden - a longitudinal population-based register study.

PubMed

Polyzoi, Maria; Ahnemark, Ewa; Medin, Emma; Ginsberg, Ylva

2018-01-01

Although the worldwide prevalence of attention-deficit/hyperactivity disorder (ADHD) in adults is estimated to be between 2% and 5%, it is considered to be underdiagnosed. This register study explored the prevalence of diagnosed ADHD and incidence of newly diagnosed ADHD in Swedish adults over time, and assessed comorbidities and pharmacologic treatment. National Patient Register data were used to estimate the overall prevalence of adults (≥18 years) with a registered ADHD diagnosis from 2006 to 2011, and the incidence of newly registered diagnoses from 2007 to 2011. Data from the Prescribed Drug Register were used to estimate the mean dose of the most frequently prescribed ADHD medication. The estimated annual prevalence (N=44,364) of diagnosed ADHD increased from 0.58 per 1,000 persons in 2006 to 3.54 per 1,000 persons in 2011. The estimated annual incidence of newly diagnosed ADHD (N=24,921) increased from 0.39 per 1,000 persons to 0.90 per 1,000 persons between 2007 and 2011. At least one comorbidity was diagnosed in 52.6% of adults with ADHD (54.0% of newly diagnosed adults), with anxiety, substance use disorders, and depression being the most common. Among all adults with ADHD, 78.9% (65.7% of newly diagnosed adults) were prescribed ADHD medication and one-third were prescribed more than one add-on medication. Osmotic release oral system methylphenidate was the most commonly used medication. The mean daily dose was 51.5 mg, and was significantly higher in males, patients with substance use disorders, patients with drug holidays, and patients with at least one add-on medication. The most frequent concomitant medications were anxiolytics and hypnotics. In Sweden, the number of adults diagnosed with ADHD increased between 2006 and 2011, and the majority of patients were prescribed ADHD-specific medication. Over one-half of patients had psychiatric comorbidities; one-third were prescribed more than one add-on medication. Consumption of pharmacologic ADHD

Potential Impact of DSM-5 Criteria on Autism Spectrum Disorder Prevalence Estimates

PubMed Central

Maenner, Matthew J.; Rice, Catherine E.; Arneson, Carrie L.; Cunniff, Christopher; Schieve, Laura A.; Carpenter, Laura A.; Van Naarden Braun, Kim; Kirby, Russell S.; Bakian, Amanda V.; Durkin, Maureen S.

2014-01-01

IMPORTANCE The DSM-5 contains revised diagnostic criteria for autism spectrum disorder (ASD) from the DSM-IV-TR. Potential impacts of the new criteria on ASD prevalence are unclear. OBJECTIVE To assess potential effects of the DSM-5 ASD criteria on ASD prevalence estimation by retrospectively applying the new criteria to population-based surveillance data collected for previous ASD prevalence estimation. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional, population-based ASD surveillance based on clinician review of coded behaviors documented in children’s medical and educational evaluations from 14 geographically defined areas in the United States participating in the Autism and Developmental Disabilities Monitoring (ADDM) Network in 2006 and 2008. This study included 8-year-old children living in ADDM Network study areas in 2006 or 2008, including 644 883 children under surveillance, of whom 6577 met surveillance ASD case status based on the DSM-IV-TR. MAIN OUTCOMES AND MEASURES Proportion of children meeting ADDM Network ASD criteria based on the DSM-IV-TR who also met DSM-5 criteria; overall prevalence of ASD using DSM-5 criteria. RESULTS Among the 6577 children classified by the ADDM Network as having ASD based on the DSM-IV-TR, 5339 (81.2%) met DSM-5 ASD criteria. This percentage was similar for boys and girls but higher for those with than without intellectual disability (86.6% and 72.5%, respectively; P < .001). A total of 304 children met DSM-5 ASD criteria but not current ADDM Network ASD case status. Based on these findings, ASD prevalence per 1000 for 2008 would have been 10.0 (95% CI, 9.6–10.3) using DSM-5 criteria compared with the reported prevalence based on DSM-IV-TR criteria of 11.3 (95% CI, 11.0–11.7). CONCLUSIONS AND RELEVANCE Autism spectrum disorder prevalence estimates will likely be lower under DSM-5 than under DSM-IV-TR diagnostic criteria, although this effect could be tempered by future adaptation of diagnostic practices and

The estimated risk for coronary heart disease and prevalence of dyslipidemia among workers of information technology industries in Taiwan.

PubMed

Yang, Shao-Chi; Chien, Kuo-Liong; Tsai, Wei-I; Ho, Yi-Lwun; Chen, Ming-Fong

2011-03-18

Individuals working in information technology (IT) industries suffer from high work stress, possibly causing adverse impacts on their health. However, studies of cardiovascular risk factors among these workers are lacking. The aims of this study were to evaluate the estimated risk for coronary heart disease (CHD) and prevalence of dyslipidemia among IT workers. A total of 941 employees from 11 IT companies were enrolled and the anthropometrics and serum lipid profiles were measured. The 10-year risk for CHD was calculated based on the Framingham risk score. Compared with lipid profiles in a representative sample (n=6589), IT workers had a significantly higher prevalence of obesity, hypercholesterolemia, low level of HDL-C, and high level of LDL-C in each age group. Their overall estimated 10-year risk for CHD was higher than the average risk of an age- and gender-matched population (2.91% vs. 2.79%, p=0.027). Working for more than 10h/day was associated with a higher estimated CHD risk (3.62% vs. 2.54%, p<0.01). A higher prevalence of hyperlipidemia was noted among IT workers. Their estimated 10-year CHD risk was also higher than average. More aggressive interventions to reduce the risk of CHD in this population are needed. Copyright © 2010 Elsevier B.V. All rights reserved.

[Evaluation of estimation of prevalence ratio using bayesian log-binomial regression model].

PubMed

Gao, W L; Lin, H; Liu, X N; Ren, X W; Li, J S; Shen, X P; Zhu, S L

2017-03-10

To evaluate the estimation of prevalence ratio ( PR ) by using bayesian log-binomial regression model and its application, we estimated the PR of medical care-seeking prevalence to caregivers' recognition of risk signs of diarrhea in their infants by using bayesian log-binomial regression model in Openbugs software. The results showed that caregivers' recognition of infant' s risk signs of diarrhea was associated significantly with a 13% increase of medical care-seeking. Meanwhile, we compared the differences in PR 's point estimation and its interval estimation of medical care-seeking prevalence to caregivers' recognition of risk signs of diarrhea and convergence of three models (model 1: not adjusting for the covariates; model 2: adjusting for duration of caregivers' education, model 3: adjusting for distance between village and township and child month-age based on model 2) between bayesian log-binomial regression model and conventional log-binomial regression model. The results showed that all three bayesian log-binomial regression models were convergence and the estimated PRs were 1.130(95 %CI : 1.005-1.265), 1.128(95 %CI : 1.001-1.264) and 1.132(95 %CI : 1.004-1.267), respectively. Conventional log-binomial regression model 1 and model 2 were convergence and their PRs were 1.130(95 % CI : 1.055-1.206) and 1.126(95 % CI : 1.051-1.203), respectively, but the model 3 was misconvergence, so COPY method was used to estimate PR , which was 1.125 (95 %CI : 1.051-1.200). In addition, the point estimation and interval estimation of PRs from three bayesian log-binomial regression models differed slightly from those of PRs from conventional log-binomial regression model, but they had a good consistency in estimating PR . Therefore, bayesian log-binomial regression model can effectively estimate PR with less misconvergence and have more advantages in application compared with conventional log-binomial regression model.

Estimating the prevalence of 26 health-related indicators at neighbourhood level in the Netherlands using structured additive regression.

PubMed

van de Kassteele, Jan; Zwakhals, Laurens; Breugelmans, Oscar; Ameling, Caroline; van den Brink, Carolien

2017-07-01

Local policy makers increasingly need information on health-related indicators at smaller geographic levels like districts or neighbourhoods. Although more large data sources have become available, direct estimates of the prevalence of a health-related indicator cannot be produced for neighbourhoods for which only small samples or no samples are available. Small area estimation provides a solution, but unit-level models for binary-valued outcomes that can handle both non-linear effects of the predictors and spatially correlated random effects in a unified framework are rarely encountered. We used data on 26 binary-valued health-related indicators collected on 387,195 persons in the Netherlands. We associated the health-related indicators at the individual level with a set of 12 predictors obtained from national registry data. We formulated a structured additive regression model for small area estimation. The model captured potential non-linear relations between the predictors and the outcome through additive terms in a functional form using penalized splines and included a term that accounted for spatially correlated heterogeneity between neighbourhoods. The registry data were used to predict individual outcomes which in turn are aggregated into higher geographical levels, i.e. neighbourhoods. We validated our method by comparing the estimated prevalences with observed prevalences at the individual level and by comparing the estimated prevalences with direct estimates obtained by weighting methods at municipality level. We estimated the prevalence of the 26 health-related indicators for 415 municipalities, 2599 districts and 11,432 neighbourhoods in the Netherlands. We illustrate our method on overweight data and show that there are distinct geographic patterns in the overweight prevalence. Calibration plots show that the estimated prevalences agree very well with observed prevalences at the individual level. The estimated prevalences agree reasonably well with the

Differences between the prevalence of obesity and weight exceded estimated according to reported or direct measurement in adult people of Valencian Region

PubMed

Jiménez-Talamantes, Raquel; Rizk Hernández, Jennifer; Quiles Izquierdo, Joan

2017-02-01

Introduction: The assessment of obesity in health surveys includes the study of the physical characteristics of human body. Anthropometrical dates can be obtained by measurement or by interview. According the method that we were used we can estimate different values for frequencies of this problem. Objectives: Measure the discrepancies of the frequency of obesity and overweight estimated with data of height and weight obtained by interview respect to those measured in a population survey. Methods: Cross-sectional survey of a sample of 1,153 adult subjects, where height and weight data reported and measured were compared by Pearson correlation. It was estimated the prevalence of obesity and overweight by two methods and we calculated the Kappa’s index, the sensitivity and specifi city for to define the predictive capacity of reported data. Results: The values of weight, height and BMI by declared and measured data presented a correlation of 0.96, 0.93 and 0.91, respectively. The prevalence of obesity was 16.4% with declared data and 23.3% for measured data (kappa = 0.68), sensitivity 63.2% and specifi city 97.9%. The prevalence of excess of weight was 51.4% with declared data and 61.1% for measured data (kappa = 0.73), sensitivity 81.3% and specificity 95.3%. These differences were statistically signifi cant. Conclusions: There is an underestimation of the prevalence of obesity and excess of weight in populations when anthropometric data were used but in good agreement and specificity was found when measured data are used.

Low Estimated Glomerular Filtration Rate Is Prevalent among North Korean Refugees in South Korea

PubMed Central

Song, Young-Soo

2018-01-01

Background The number of North Korean refugees entering South Korea is rising. Few studies have investigated the risk of non-communicable disease in North Korean refugees. Moreover, kidney insufficiency, a risk factor for cardiovascular disease, has not been studied in this population. We compared the prevalence of non-communicable disease and kidney function in North Korean refugees and South Koreans. Methods Our study was conducted using a case-control design. We enrolled 118 North Korean refugees from the Hana Center and selected 472 randomly sampled South Korean individuals as controls, who were age- and sex-matched with the North Korean refugees in a ratio of 1:4, from the 2014 Korea National Health and Nutrition Examination Survey database. Results The prevalence of non-communicable disease did not differ significantly between the groups; however, a low estimated glomerular filtration rate (eGFR; <90 mL/min per 1.73 m2) was more prevalent in the North Korean refugees than in the South Korean population (52.1% vs. 29.9%, P<0.001). After adjusting for covariates and weight gain after escape, the prevalence of a low eGFR was associated with the length of residence in South Korea (odds ratio, 2.84; 95% confidence interval, 1.02–7.89). Conclusion The prevalence of non-communicable disease did not differ between North Korean refugees and the South Korean population, while a low eGFR was more prevalent in North Korean refugees than in South Koreans. Moreover, after adjusting for other covariates, the prevalence of a low eGFR in North Korean refugees was associated with the length of residence in South Korea. PMID:29788704

Low Estimated Glomerular Filtration Rate Is Prevalent among North Korean Refugees in South Korea.

PubMed

Song, Young-Soo; Choi, Seong-Woo

2018-05-01

The number of North Korean refugees entering South Korea is rising. Few studies have investigated the risk of non-communicable disease in North Korean refugees. Moreover, kidney insufficiency, a risk factor for cardiovascular disease, has not been studied in this population. We compared the prevalence of non-communicable disease and kidney function in North Korean refugees and South Koreans. Our study was conducted using a case-control design. We enrolled 118 North Korean refugees from the Hana Center and selected 472 randomly sampled South Korean individuals as controls, who were age- and sex-matched with the North Korean refugees in a ratio of 1:4, from the 2014 Korea National Health and Nutrition Examination Survey database. The prevalence of non-communicable disease did not differ significantly between the groups; however, a low estimated glomerular filtration rate (eGFR; <90 mL/min per 1.73 m 2 ) was more prevalent in the North Korean refugees than in the South Korean population (52.1% vs. 29.9%, P<0.001). After adjusting for covariates and weight gain after escape, the prevalence of a low eGFR was associated with the length of residence in South Korea (odds ratio, 2.84; 95% confidence interval, 1.02-7.89). The prevalence of non-communicable disease did not differ between North Korean refugees and the South Korean population, while a low eGFR was more prevalent in North Korean refugees than in South Koreans. Moreover, after adjusting for other covariates, the prevalence of a low eGFR in North Korean refugees was associated with the length of residence in South Korea.

Prevalence of Transgender Depends on the “Case” Definition: A Systematic Review

PubMed Central

Collin, Lindsay; Reisner, Sari L.; Tangpricha, Vin; Goodman, Michael

2016-01-01

Background We conducted a systematic review and meta-analysis to evaluate how various definitions of “transgender” may affect prevalence estimates. Methods PubMed, Embase, and Medline were searched to identify studies reporting prevalence estimates of transgender in a population. All studies were grouped based on the case definition applied to the numerator. Summary estimates were derived using a random-effects model for total prevalence of transgender and for male-to-female (MTF) and female-to-male (FTM) subgroups. Overall and stratum-specific meta-prevalence estimates (mPs) and 95% confidence intervals (CIs) were accompanied by tests for heterogeneity, and meta-regressions to assess sources of heterogeneity. Results A total of 32 studies met the inclusion criteria for the systematic review. Of those, 27 studies provided necessary data for a meta-analysis. Overall mP (95% CI) per 100,000 population was 9.2 (4.9, 13.6) for surgical or hormonal gender affirmation therapy and 6.8 (4.6–9.1) for transgender-related diagnoses. Among studies assessing self-reported transgender identity, the mP was 871 (95% 519, 1224); however this result was influenced by a single outlier study. After removal of that study, the mP changed to 355 (95% CI 144, 566). Significant heterogeneity was observed in most analyses. Conclusions The empirical literature on the prevalence of transgender highlights the importance of adhering to specific case definitions because the results may range by orders of magnitude. Standardized and routine collection of transgender data is recommended. PMID:27045261

Estimated prevalence of compulsive buying behavior in the United States.

PubMed

Koran, Lorrin M; Faber, Ronald J; Aboujaoude, Elias; Large, Michael D; Serpe, Richard T

2006-10-01

Compulsive buying (uncontrolled urges to buy, with resulting significant adverse consequences) has been estimated to affect from 1.8% to 16% of the adult U.S. population. To the authors' knowledge, no study has used a large general population sample to estimate its prevalence. The authors conducted a random sample, national household telephone survey in the spring and summer of 2004 and interviewed 2,513 adults. The interviews addressed buying attitudes and behaviors, their consequences, and the respondents' financial and demographic data. The authors used a clinically validated screening instrument, the Compulsive Buying Scale, to classify respondents as either compulsive buyers or not. The rate of response was 56.3%, which compares favorably with rates in federal national health surveys. The cooperation rate was 97.6%. Respondents included a higher percentage of women and people ages 55 and older than the U.S. adult population. The estimated point prevalence of compulsive buying among respondents was 5.8% (by gender: 6.0% for women, 5.5% for men). The gender-adjusted prevalence rate was 5.8%. Compared with other respondents, compulsive buyers were younger, and a greater proportion reported incomes under 50,000 US dollars. They exhibited more maladaptive responses on most consumer behavior measures and were more than four times less likely to pay off credit card balances in full. A study using clinically valid interviews is needed to evaluate these results. The emotional and functional toll of compulsive buying and the frequency of comorbid psychiatric disorders suggests that studies of treatments and social interventions are warranted.

The impact of measurement differences on cross-country depression prevalence estimates: A latent transition analysis.

PubMed

Scorza, Pamela; Masyn, Katherine; Salomon, Joshua A; Betancourt, Theresa S

2018-01-01

Depression is currently the second largest contributor to non-fatal disease burden globally. For that reason, economic evaluations are increasingly being conducted using data from depression prevalence estimates to analyze return on investments for services that target mental health. Psychiatric epidemiology studies have reported large cross-national differences in the prevalence of depression. These differences may impact the cost-effectiveness assessments of mental health interventions, thereby affecting decisions regarding government and multi-lateral investment in mental health services. Some portion of the differences in prevalence estimates across countries may be due to true discrepancies in depression prevalence, resulting from differential levels of risk in environmental and demographic factors. However, some portion of those differences may reflect non-invariance in the way standard tools measure depression across countries. This paper attempts to discern the extent to which measurement differences are responsible for reported differences in the prevalence of depression across countries. This analysis uses data from the World Mental Health Surveys, a coordinated series of psychiatric epidemiology studies in 27 countries using multistage household probability samples to assess prevalence and correlates of mental disorders. Data in the current study include responses to the depression module of the World Mental Health Composite International Diagnostic Interview (CIDI) in four countries: Two high-income, western countries-the United States (n = 20, 015) and New Zealand (n = 12,992)-an upper-middle income sub-Saharan African country, South Africa (n = 4,351), and a lower-middle income sub-Saharan African country, Nigeria (n = 6,752). Latent class analysis, a type of finite mixture modeling, was used to categorize respondents into underlying categories based on the variation in their responses to questions in each of three sequential parts of the CIDI

The prevalence and specific characteristics of hospitalised pressure ulcer patients: A multicentre cross-sectional study.

PubMed

Zhou, Qing; Yu, Ting; Liu, Yuan; Shi, Ruifen; Tian, Suping; Yang, Chaoxia; Gan, Huaxiu; Zhu, Yanying; Liang, Xia; Wang, Ling; Wu, Zhenhua; Huang, Jinping; Hu, Ailing

2018-02-01

To ascertain the pressure ulcer prevalence in secondary and tertiary general hospitals in different areas of Guangdong Province in China and explore the possible risk factors that are related to pressure ulcers. Few multicentre studies have been conducted on pressure ulcer prevalence in Chinese hospitals. A cross-sectional study design was used. Data from a total of 25,264 patients were included in the analysis at 25 hospitals in China. The investigators were divided into two groups. The investigators in group 1 examined the patients' skin. When a pressure ulcer was found, a pressure ulcer assessment form was completed. The investigators in group 2 provided guidance to the nurses, who assessed all patients and completed another questionnaire. A multivariate logistic regression analysis was used to analyse the relationship between the possible risk factors and pressure ulcer. The overall prevalence rate of pressure ulcers in the 25 hospitals ranged from 0%-3.49%, with a mean of 1.26%. The most common stage of the pressure ulcers was stage II (41.4%); most common anatomical locations were sacrum (39.5%) and the feet (16.4%). Braden score (p < .001), expected length of stay (p < .001), incontinence (p < .001), care group (p = .011), hospital location (p < .001), type of hospitals (p = .004), ages of patients (p < .001) were associations of pressure ulcers from the multivariate logistic regression analysis. The overall prevalence rate of pressure ulcers in Chinese hospitals was lower than that reported in previous investigations. Specific characteristics of pressure ulcer patients were as follows: low Braden score, longer expected length of stay, double incontinence, an ICU and a medical ward, hospital location in the Pearl River Delta, a university hospital and an older patient. The survey could make managers know their prevalence level of pressure ulcers and provide priorities for clinical nurses. © 2017 John Wiley & Sons Ltd.

Vertebral endplate signal changes (Modic change): a systematic literature review of prevalence and association with non-specific low back pain

PubMed Central

Karppinen, Jaro; Sorensen, Joan S.; Niinimäki, Jaakko; Leboeuf-Yde, Charlotte

2008-01-01

The prevalence of “vertebral endplate signal changes” (VESC) and its association with low back pain (LBP) varies greatly between studies. This wide range in reported prevalence rates and associations with LBP could be explained by differences in the definitions of VESC, LBP, or study sample. The objectives of this systematic critical review were to investigate the current literature in relation to the prevalence of VESC (including Modic changes) and the association with non-specific low back pain (LBP). The MEDLINE, EMBASE, and SveMED databases were searched for the period 1984 to November 2007. Included were the articles that reported the prevalence of VESC in non-LBP, general, working, and clinical populations. Included were also articles that investigated the association between VESC and LBP. Articles on specific LBP conditions were excluded. A checklist including items related to the research questions and overall quality of the articles was used for data collection and quality assessment. The reported prevalence rates were studied in relation to mean age, gender, study sample, year of publication, country of study, and quality score. To estimate the association between VESC and LBP, 2 × 2 tables were created to calculate the exact odds ratio (OR) with 95% confidence intervals. Eighty-two study samples from 77 original articles were identified and included in the analysis. The median of the reported prevalence rates for any type of VESC was 43% in patients with non-specific LBP and/or sciatica and 6% in non-clinical populations. The prevalence was positively associated with age and was negatively associated with the overall quality of the studies. A positive association between VESC and non-specific LBP was found in seven of ten studies from the general, working, and clinical populations with ORs from 2.0 to 19.9. This systematic review shows that VESC is a common MRI-finding in patients with non-specific LBP and is associated with pain. However, it

Prevalence and burden of chronic kidney disease among the general population and high-risk groups in Africa: a systematic review

PubMed Central

Abd ElHafeez, Samar; Bolignano, Davide; D’Arrigo, Graziella; Dounousi, Evangelia; Tripepi, Giovanni; Zoccali, Carmine

2018-01-01

Objectives While increasing attention is paid to the rising prevalence of chronic diseases in Africa, there is little focus on chronic kidney disease (CKD). This systematic review assesses CKD burden among the general population and high-risk groups on the entire African continent. Design, setting and participants We searched Medline and PubMed databases for articles published between 1 January 1995 and 7 April 2017 by sensitive search strategies focusing on CKD surveys at the community level and high-risk groups. In total, 7918 references were evaluated, of which 7766 articles were excluded because they did not meet the inclusion criteria. Thus, 152 studies were included in the final analysis. Outcome measurement The prevalence of CKD in each study group was expressed as a range and pooled prevalence rate of CKD was calculated as a point estimate and 95% CI. No meta-analysis was done. Data were presented for different populations. Results In the community-level studies, based on available medium-quality and high-quality studies, the prevalence of CKD ranged from 2% to 41% (pooled prevalence: 10.1%; 95% CI 9.8% to 10.5%). The prevalence of CKD in the high-risk groups ranged from 1% to 46% (pooled prevalence: 5.6%; 95% CI 5.4% to 5.8%) in patients with HIV (based on available medium-quality and high-quality studies), 11%–90% (pooled prevalence: 24.7%; 95% CI 23.6% to 25.7%) in patients with diabetes (based on all available studies which are of low quality except four of medium quality) and 13%–51% (pooled prevalence: 34.5%; 95 % CI 34.04% to 36%) in patients with hypertension (based on all available studies which are of low quality except two of medium quality). Conclusion In Africa, CKD is a public health problem, mainly attributed to high-risk conditions as hypertension and diabetes. The poor data quality restricts the validity of the findings and draws the attention to the importance of designing future robust studies. PMID:29326180

An estimate of the prevalence of hypertension in Nigeria: a systematic review and meta-analysis.

PubMed

Adeloye, Davies; Basquill, Catriona; Aderemi, Adewale V; Thompson, Jacqueline Y; Obi, Felix A

2015-02-01

Hypertension is a leading cause of morbidity and mortality in Africa, and Nigeria, the most populous country in the continent, hugely contributes to this burden. To provide an improved estimate of the prevalence and number of cases of hypertension in Nigeria based on the cut-off 'at least 140/90  mmHg', towards ensuring better awareness, control and policy response in the country. We conducted a systematic search of Medline, EMBASE and Global Health from January 1980 to December 2013 for population-based studies providing estimates on the prevalence of hypertension in Nigeria. From the extracted crude prevalence rates, we conducted a random-effects meta-analysis, and further estimated the overall awareness rate of hypertension in Nigeria, expressed as percentage of all hypertension cases. We applied a meta-regression epidemiological modelling, using United Nations population demographics for the years 2010 and 2030, to determine the prevalence and number of cases of hypertension in Nigeria for the 2 years. Our search returned 2260 publications, 27 of which met our selection criteria. From the random-effects meta-analysis, we estimated an overall hypertension prevalence of 28.9% (25.1, 32.8), with a prevalence of 29.5% (24.8, 34.3) among men and 25.0% (20.2, 29.7) among women. We estimated a prevalence of 30.6% (24.5, 36.6) and 26.4% (19.4, 33.4) among urban and rural dwellers, respectively. The pooled awareness rate of hypertension was 17.4% (11.4, 23.3). The overall mean SBP was 128.6 (125.5, 130.8) mmHg, and the DBP was 80.6 (78.5, 82.7) mmHg. From our modelling, we estimated about 20.8 million cases of hypertension in Nigeria among people aged at least 20 years in 2010, with a prevalence of 28.0% (24.6, 31.9) in both sexes - 30.7% (24.9, 33.7) among men and 25.2% (22.7, 31.9) among women. By 2030, we projected an increase to 39.1 million cases of hypertension among people aged at least 20 years with a prevalence of 30.8% (24.5, 33.7) in both sexes - 32.6% (27

Estimation of Prevalence of the Left Ventricular Noncompaction Among Adults.

PubMed

Ronderos, Ricardo; Avegliano, Gustavo; Borelli, Evelyn; Kuschnir, Paola; Castro, Florencia; Sanchez, Gustavo; Perea, Gabriel; Corneli, Mariana; Zanier, Maria M; Andres, Sol; Aranda, Adriana; Conde, Diego; Trivi, Marcelo

2016-09-15

The prevalence of left ventricular noncompacted myocardium (LVNC) is not clearly defined yet. The goal of this study was to prospectively assess the prevalence of LVNC in a population of patients assessed for cardiovascular disease and to analyze the coincidence between observers using the echocardiographic criteria for diagnosis of LVNC. We included patients prospectively during a 1-year period. To analyze the concordance between different observers, we performed a blind analysis of 50 patients between 7 operators to calculate Kappa index for each criteria. The analysis of concordance for final diagnosis of LVNC was free-marginal kappa: 0.94. A total of 10,857 patients underwent echocardiography; 2,931 (27%) were normal. LVNC was found in 26 patients (prevalence = 0.24%), 16 patients were women, mean age of 52.6 years. Patients were divided into 2 groups; group A: ejection fraction (EF) <50% (n = 20) and group B: normal systolic function (n = 6). Among abnormal studies, 294 (2.7%) were dilated cardiomyopathies (DCs) Patients with LVNC and EF <50% comprised 6.8% of DC (20 of 294) and 24% (20 of 75) of patients with idiopathic DC (p <0.0001). Group A patients were older and with less presence of women (both p <0.05). In conclusion, the prevalence of LVNC in a population assessed for cardiovascular diseases is low. In contrast, it is very high in the subgroup of patients with idiopathic DC. The group of patients with LVNC and normal LVEF is younger and with a higher presence of women than those with LVNC and depressed LVEF. Coincidence between operators is very good for the identification of echocardiographic criteria. Copyright © 2016 Elsevier Inc. All rights reserved.

Estimated prevalence of halitosis: a systematic review and meta-regression analysis.

PubMed

Silva, Manuela F; Leite, Fábio R M; Ferreira, Larissa B; Pola, Natália M; Scannapieco, Frank A; Demarco, Flávio F; Nascimento, Gustavo G

2018-01-01

This study aims to conduct a systematic review to determine the prevalence of halitosis in adolescents and adults. Electronic searches were performed using four different databases without restrictions: PubMed, Scopus, Web of Science, and SciELO. Population-based observational studies that provided data about the prevalence of halitosis in adolescents and adults were included. Additionally, meta-analyses, meta-regression, and sensitivity analyses were conducted to synthesize the evidence. A total of 584 articles were initially found and considered for title and abstract evaluation. Thirteen articles met inclusion criteria. The combined prevalence of halitosis was found to be 31.8% (95% CI 24.6-39.0%). Methodological aspects such as the year of publication and the socioeconomic status of the country where the study was conducted seemed to influence the prevalence of halitosis. Our results demonstrated that the estimated prevalence of halitosis was 31.8%, with high heterogeneity between studies. The results suggest a worldwide trend towards a rise in halitosis prevalence. Given the high prevalence of halitosis and its complex etiology, dental professionals should be aware of their roles in halitosis prevention and treatment.

Estimating cancer incidence, prevalence, and the number of cancer patients treated with antitumor therapy in 2015 and 2020 -  analysis of the Czech National Cancer Registry.

PubMed

Dusek, L; Pavlík, T; Májek, O; Büchler, T; Muzik, J; Maluskova, D; Koptíková, J; Bortlicek, Z; Abrahámová, J

2015-01-01

Cancer burden in the Czech population ranks among the highest worldwide, which introduces a strong need for a prospective modelling of cancer incidence and prevalence rates. Moreover, a prediction of number of cancer patients requiring active antitumor therapy is also an important issue. This paper presents the stage-specific predictions of cancer incidence and prevalence, and the stage- and region-specific patients requiring active antitumor therapy for the most common cancer diagnoses in the Czech Republic for years 2015 and 2020. The stage-specific estimates are also presented with regard to the treatment phase as newly diagnosed patients, patients treated for non-terminal recurrence, and patients treated for terminal recurrence. Data of the Czech National Cancer Registry from 1977 to 2011 has been used for the analysis, omitting the records of patients diagnosed as death certificate only or at autopsy. In total, 1,777,775 incidences have been considered for the estimation using a statistical model utilizing solely the population-based cancer registry data. All estimates have been calculated with respect to the changing demographic structure of the Czech population and the clinical stage at diagnosis. Considering year 2011 as the baseline, we predict 89%, 15%, 31% and 32% increase in prostate, colorectal, female breast and lung cancer incidence, respectively, in 2020 resulting in 13,153, 9,368, 8,695, and 8,604 newly dia-g--nosed cancer patients in that year, respectively. Regarding cancer prevalence in 2020, the estimated increase is 140%, 40%, 51%, and 17% for prostate, colorectal, female breast and lung cancer, respectively, meaning that more than 100,000 prevalent female breast cancer patients as well as more than 100,000 prevalent prostate cancer patients are expected in the Czech Republic. The estimated numbers of patients requiring active antitumor therapy for prostate, colorectal, female breast and lung cancer in the Czech Republic in 2020 are 23,652, 14

The association between major depression prevalence and sex becomes weaker with age.

PubMed

Patten, Scott B; Williams, Jeanne V A; Lavorato, Dina H; Wang, Jian Li; Bulloch, Andrew G M; Sajobi, Tolulope

2016-02-01

Women have a higher prevalence of major depressive episodes (MDE) than men, and the annual prevalence of MDE declines with age. Age by sex interactions may occur (a weakening of the sex effect with age), but are easily overlooked since individual studies lack statistical power to detect interactions. The objective of this study was to evaluate age by sex interactions in MDE prevalence. In Canada, a series of 10 national surveys conducted between 1996 and 2013 assessed MDE prevalence in respondents over the age of 14. Treating age as a continuous variable, binomial and linear regression was used to model age by sex interactions in each survey. To increase power, the survey-specific interaction coefficients were then pooled using meta-analytic methods. The estimated interaction terms were homogeneous. In the binomial regression model I (2) was 31.2 % and was not statistically significant (Q statistic = 13.1, df = 9, p = 0.159). The pooled estimate (-0.004) was significant (z = 3.13, p = 0.002), indicating that the effect of sex became weaker with increasing age. This resulted in near disappearance of the sex difference in the 75+ age group. This finding was also supported by an examination of age- and sex-specific estimates pooled across the surveys. The association of MDE prevalence with sex becomes weaker with age. The interaction may reflect biological effect modification. Investigators should test for, and consider inclusion of age by sex interactions in epidemiological analyses of MDE prevalence.

Estimated prevalence and incidence of diagnosed ADHD and health care utilization in adults in Sweden – a longitudinal population-based register study

PubMed Central

Polyzoi, Maria; Ahnemark, Ewa; Medin, Emma; Ginsberg, Ylva

2018-01-01

Background Although the worldwide prevalence of attention-deficit/hyperactivity disorder (ADHD) in adults is estimated to be between 2% and 5%, it is considered to be underdiagnosed. This register study explored the prevalence of diagnosed ADHD and incidence of newly diagnosed ADHD in Swedish adults over time, and assessed comorbidities and pharmacologic treatment. Methods National Patient Register data were used to estimate the overall prevalence of adults (≥18 years) with a registered ADHD diagnosis from 2006 to 2011, and the incidence of newly registered diagnoses from 2007 to 2011. Data from the Prescribed Drug Register were used to estimate the mean dose of the most frequently prescribed ADHD medication. Results The estimated annual prevalence (N=44,364) of diagnosed ADHD increased from 0.58 per 1,000 persons in 2006 to 3.54 per 1,000 persons in 2011. The estimated annual incidence of newly diagnosed ADHD (N=24,921) increased from 0.39 per 1,000 persons to 0.90 per 1,000 persons between 2007 and 2011. At least one comorbidity was diagnosed in 52.6% of adults with ADHD (54.0% of newly diagnosed adults), with anxiety, substance use disorders, and depression being the most common. Among all adults with ADHD, 78.9% (65.7% of newly diagnosed adults) were prescribed ADHD medication and one-third were prescribed more than one add-on medication. Osmotic release oral system methylphenidate was the most commonly used medication. The mean daily dose was 51.5 mg, and was significantly higher in males, patients with substance use disorders, patients with drug holidays, and patients with at least one add-on medication. The most frequent concomitant medications were anxiolytics and hypnotics. Conclusion In Sweden, the number of adults diagnosed with ADHD increased between 2006 and 2011, and the majority of patients were prescribed ADHD-specific medication. Over one-half of patients had psychiatric comorbidities; one-third were prescribed more than one add-on medication

Global trends in dietary micronutrient supplies and estimated prevalence of inadequate intakes

PubMed Central

Arsenault, Joanne E.; Smith, Matthew R.

2017-01-01

Understanding dietary patterns is vital to reducing the number of people experiencing hunger (about 795 million), micronutrient deficiencies (2 billion), and overweight or obesity (2.1 billion). We characterize global trends in dietary quality by estimating micronutrient density of the food supply, prevalence of inadequate intake of 14 micronutrients, and average prevalence of inadequate intake of these micronutrients for all countries between 1961 and 2011. Over this 50-year period, the estimated prevalence of inadequate intakes of micronutrients has declined in all regions due to increased total production of food and/or micronutrient density. This decline has been particularly strong in East and Southeast Asia and weaker in South Asia and sub-Saharan Africa. Sub-Saharan Africa is the only region where dietary micronutrient density has declined over this 50-year period. At the global level, micronutrients with the lowest levels of adequate estimated intake are calcium, iron, vitamin A, and zinc, but there are strong differences between countries and regions. Fortification has reduced the estimated prevalence of inadequate micronutrient intakes in all low-income regions, except South Asia. The food supply in many countries is still far below energy requirements, which suggests a need to increase the availability and accessibility of nutritious foods. Countries where the food energy supply is adequate show a very large variation in dietary quality, and in many of these countries people would benefit from more diverse diets with a greater proportion of micronutrient-dense foods. Dietary quality can be improved through fortification, biofortification, and agricultural diversification, as well as efforts to improve access to and use of micronutrient-dense foods and nutritional knowledge. Reducing poverty and increasing education, especially of women, are integral to sustainably addressing malnutrition. PMID:28399168

Toxocara infection in the United States: the relevance of poverty, geography and demography as risk factors, and implications for estimating county prevalence.

PubMed

Congdon, Peter; Lloyd, Patsy

2011-02-01

To estimate Toxocara infection rates by age, gender and ethnicity for US counties using data from the National Health and Nutrition Examination Survey (NHANES). After initial analysis to account for missing data, a binary regression model is applied to obtain relative risks of Toxocara infection for 20,396 survey subjects. The regression incorporates interplay between demographic attributes (age, ethnicity and gender), family poverty and geographic context (region, metropolitan status). Prevalence estimates for counties are then made, distinguishing between subpopulations in poverty and not in poverty. Even after allowing for elevated infection risk associated with poverty, seropositivity is elevated among Black non-Hispanics and other ethnic groups. There are also distinct effects of region. When regression results are translated into county prevalence estimates, the main influences on variation in county rates are percentages of non-Hispanic Blacks and county poverty. For targeting prevention it is important to assess implications of national survey data for small area prevalence. Using data from NHANES, the study confirms that both individual level risk factors and geographic contextual factors affect chances of Toxocara infection.

Age-specific prevalence of human papilloma virus infection among Nigerian women.

PubMed

Akarolo-Anthony, Sally N; Famooto, Ayo O; Dareng, Eileen O; Olaniyan, Olayinka B; Offiong, Richard; Wheeler, Cosette M; Adebamowo, Clement A

2014-06-27

Inconsistent trends in HPV prevalence by age have been described in Africa. We examined the age prevalence pattern and distribution of 37 HPV-DNA types among urban Nigerian women. The study population was a sample of 278 women who presented to cervical cancer screening programs in Abuja, Nigeria, between April and August 2012. Using a nurse administered questionnaire, information on demographic characteristics and risk factors of cervical cancer was collected and samples of cervical exfoliated cells were obtained from all participants. Roche Linear Array HPV Genotyping Test® was used to characterize prevalent HPV and log-binomial regression models were used to examine the association between potential correlates and the prevalence of HPV infection. The mean age (SD) of the women enrolled was 38 (8) years. The overall prevalence of HPV was 37%. HPV 35 was the most prevalent HPV type in the study population. Among women age ≤ 30 years, 52% had HPV infection compared to 23% of those women who were older than 45 years (p = 0.006). We observed a significant linear association between age and the prevalence of HPV infections. The prevalence ratio (PR) and 95% confidence interval (CI) was 2.26 (1.17, 4.34) for any HPV infection, 3.83 (1.23, 11.94) for Group 1 HPV (definite carcinogens), and 2.19 (0.99, 4.84) for Group 2a or 2b HPV (probable or possible carcinogens) types, among women aged 18-30 years, compared to women who were older than 45 years. The prevalence of HPV infection was highest among younger women and decreased steadily with age among this population of urban Nigerian women.

ADHD Is Highly Prevalent in Patients Seeking Treatment for Cannabis Use Disorders.

PubMed

Notzon, Daniel P; Pavlicova, Martina; Glass, Andrew; Mariani, John J; Mahony, Amy L; Brooks, Daniel J; Levin, Frances R

2016-03-31

To estimate the prevalence of ADHD and determine an effective screening test for ADHD in a population-seeking treatment for cannabis use disorders. The Conners Adult ADHD Diagnostic Interview forDiagnostic and Statistical Manual of Mental Disorders, Fourth Edition(DSM-IV; CAADID) was used to generate sensitivity and specificity data for ADHD screening tests, which were then administered to 99 participants seeking treatment for cannabis use disorders to estimate ADHD prevalence. The prevalence estimated from the Wender Utah Rating Scale (WURS) was 45% (sensitivity = 0.88, sensitivity of 0.75), from the Conners Adult ADHD Rating Scale (CAARS) 34% (sensitivity = 0.80, specificity = 0.91), from the WURS + CAARS 36% (sensitivity = 0.71, specificity = 0.95), and from the Adult ADHD Self-Report Scale (ASRS) 46% (sensitivity = 0.61, specificity = 0.86). The prevalence of ADHD in adults seeking treatment for cannabis use disorders is estimated to be between 34% and 46%. The WURS paired with the CAARS provides excellent sensitivity and specificity for the diagnosis of ADHD in this population. © The Author(s) 2016.

Chronic migraine prevalence, disability, and sociodemographic factors: results from the American Migraine Prevalence and Prevention Study.

PubMed

Buse, Dawn C; Manack, Aubrey N; Fanning, Kristina M; Serrano, Daniel; Reed, Michael L; Turkel, Catherine C; Lipton, Richard B

2012-01-01

To estimate the prevalence and distribution of chronic migraine (CM) in the US population and compare the age- and sex-specific profiles of headache-related disability in persons with CM and episodic migraine. Global estimates of CM prevalence using various definitions typically range from 1.4% to 2.2%, but the influence of sociodemographic factors has not been completely characterized. The American Migraine Prevalence and Prevention Study mailed surveys to a sample of 120,000 US households selected to represent the US population. Data on headache frequency, symptoms, sociodemographics, and headache-related disability (using the Migraine Disability Assessment Scale) were obtained. Modified Silberstein-Lipton criteria were used to classify CM (meeting International Classification of Headache Disorders, second edition, criteria for migraine with a headache frequency of ≥15 days over the preceding 3 months). Surveys were returned by 162,756 individuals aged ≥12 years; 19,189 individuals (11.79%) met International Classification of Headache Disorders, second edition, criteria for migraine (17.27% of females; 5.72% of males), and 0.91% met criteria for CM (1.29% of females; 0.48% of males). Relative to 12 to 17 year olds, the age- and sex-specific prevalence for CM peaked in the 40s at 1.89% (prevalence ratio 4.57; 95% confidence interval 3.13-6.67) for females and 0.79% (prevalence ratio 3.35; 95% confidence interval 1.99-5.63) for males. In univariate and adjusted models, CM prevalence was inversely related to annual household income. Lower income groups had higher rates of CM. Individuals with CM had greater headache-related disability than those with episodic migraine and were more likely to be in the highest Migraine Disability Assessment Scale grade (37.96% vs. 9.50%, respectively). Headache-related disability was highest among females with CM compared with males. CM represented 7.68% of migraine cases overall, and the proportion generally increased with age

Problematic video game use: estimated prevalence and associations with mental and physical health.

PubMed

Mentzoni, Rune Aune; Brunborg, Geir Scott; Molde, Helge; Myrseth, Helga; Skouverøe, Knut Joachim Mår; Hetland, Jørn; Pallesen, Ståle

2011-10-01

A nationwide survey was conducted to investigate the prevalence of video game addiction and problematic video game use and their association with physical and mental health. An initial sample comprising 2,500 individuals was randomly selected from the Norwegian National Registry. A total of 816 (34.0 percent) individuals completed and returned the questionnaire. The majority (56.3 percent) of respondents used video games on a regular basis. The prevalence of video game addiction was estimated to be 0.6 percent, with problematic use of video games reported by 4.1 percent of the sample. Gender (male) and age group (young) were strong predictors for problematic use of video games. A higher proportion of high frequency compared with low frequency players preferred massively multiplayer online role-playing games, although the majority of high frequency players preferred other game types. Problematic use of video games was associated with lower scores on life satisfaction and with elevated levels of anxiety and depression. Video game use was not associated with reported amount of physical exercise.

Cervical HPV type-specific pre-vaccination prevalence and age distribution in Croatia.

PubMed

Sabol, Ivan; Milutin Gašperov, Nina; Matovina, Mihaela; Božinović, Ksenija; Grubišić, Goran; Fistonić, Ivan; Belci, Dragan; Alemany, Laia; Džebro, Sonja; Dominis, Mara; Šekerija, Mario; Tous, Sara; de Sanjosé, Silvia; Grce, Magdalena

2017-01-01

The main etiological factor of precancerous lesion and invasive cervical cancer are oncogenic human papillomaviruses types (HPVs). The objective of this study was to establish the distribution of the most common HPVs in different cervical lesions and cancer prior to the implementation of organized population-based cervical screening and HPV vaccination in Croatia. In this study, 4,432 cervical specimens, collected through a 16-year period, were tested for the presence of HPV-DNA by polymerase chain reaction (PCR) with three sets of broad-spectrum primers and type-specific primers for most common low-risk (LR) types (HPV-6, 11) and the most common high-risk (HR) types (HPV-16, 18, 31, 33, 45, 52, 58). Additional 35 archival formalin-fixed, paraffin embedded tissue of cervical cancer specimens were analyzed using LiPA25 assay. The highest age-specific HPV-prevalence was in the group 18-24 years, which decreased continuously with age (P<0.0001) regardless of the cytological diagnosis. The prevalence of HR-HPV types significantly increased (P<0.0001) with the severity of cervical lesions. HPV-16 was the most common type found with a prevalence (with or without another HPV-type) of 6.9% in normal cytology, 15.5% in atypical squamous cells of undetermined significance, 14.4% in low-grade squamous intraepithelial lesions, 33.3% in high-grade squamous intraepithelial lesions, and 60.9% in cervical cancer specimens (P<0.0001). This study provides comprehensive and extensive data on the distribution of the most common HPV types among Croatian women, which will enable to predict and to monitor the impact of HPV-vaccination and to design effective screening strategies in Croatia.

The global prevalence of HFE and non-HFE hemochromatosis estimated from analysis of next-generation sequencing data.

PubMed

Wallace, Daniel F; Subramaniam, V Nathan

2016-06-01

The prevalence of HFE-related hereditary hemochromatosis (HH) among European populations has been well studied. There are no prevalence data for atypical forms of HH caused by mutations in HFE2, HAMP, TFR2, or SLC40A1. The purpose of this study was to estimate the population prevalence of these non-HFE forms of HH. A list of HH pathogenic variants in publically available next-generation sequence (NGS) databases was compiled and allele frequencies were determined. Of 161 variants previously associated with HH, 43 were represented among the NGS data sets; an additional 40 unreported functional variants also were identified. The predicted prevalence of HFE HH and the p.Cys282Tyr mutation closely matched previous estimates from similar populations. Of the non-HFE forms of iron overload, TFR2-, HFE2-, and HAMP-related forms are predicted to be rare, with pathogenic allele frequencies in the range of 0.00007 to 0.0005. Significantly, SLC40A1 variants that have been previously associated with autosomal-dominant ferroportin disease were identified in several populations (pathogenic allele frequency 0.0004), being most prevalent among Africans. We have, for the first time, estimated the population prevalence of non-HFE HH. This methodology could be applied to estimate the population prevalence of a wide variety of genetic disorders.Genet Med 18 6, 618-626.

A novel, efficient method for estimating the prevalence of acute malnutrition in resource-constrained and crisis-affected settings: A simulation study.

PubMed

Frison, Severine; Kerac, Marko; Checchi, Francesco; Nicholas, Jennifer

2017-01-01

The assessment of the prevalence of acute malnutrition in children under five is widely used for the detection of emergencies, planning interventions, advocacy, and monitoring and evaluation. This study examined PROBIT Methods which convert parameters (mean and standard deviation (SD)) of a normally distributed variable to a cumulative probability below any cut-off to estimate acute malnutrition in children under five using Middle-Upper Arm Circumference (MUAC). We assessed the performance of: PROBIT Method I, with mean MUAC from the survey sample and MUAC SD from a database of previous surveys; and PROBIT Method II, with mean and SD of MUAC observed in the survey sample. Specifically, we generated sub-samples from 852 survey datasets, simulating 100 surveys for eight sample sizes. Overall the methods were tested on 681 600 simulated surveys. PROBIT methods relying on sample sizes as small as 50 had better performance than the classic method for estimating and classifying the prevalence of acute malnutrition. They had better precision in the estimation of acute malnutrition for all sample sizes and better coverage for smaller sample sizes, while having relatively little bias. They classified situations accurately for a threshold of 5% acute malnutrition. Both PROBIT methods had similar outcomes. PROBIT Methods have a clear advantage in the assessment of acute malnutrition prevalence based on MUAC, compared to the classic method. Their use would require much lower sample sizes, thus enable great time and resource savings and permit timely and/or locally relevant prevalence estimates of acute malnutrition for a swift and well-targeted response.

Prevalence, clinical profile, iron status, and subject-specific traits for excessive erythrocytosis in andean adults living permanently at 3,825 meters above sea level.

PubMed

De Ferrari, Aldo; Miranda, J Jaime; Gilman, Robert H; Dávila-Román, Victor G; León-Velarde, Fabiola; Rivera-Ch, Maria; Huicho, Luis; Bernabé-Ortiz, Antonio; Wise, Robert A; Checkley, William

2014-11-01

Excessive erythrocytosis (EE) is a prevalent condition in populations living at high altitudes (> 2,500 m above sea level). Few large population-based studies have explored the association between EE and multiple subject-specific traits including oxygen saturation, iron status indicators, and pulmonary function. We enrolled a sex-stratified and age-stratified sample of 1,065 high-altitude residents aged ≥ 35 years from Puno, Peru (3,825 m above sea level) and conducted a standardized questionnaire and physical examination that included spirometry, pulse oximetry, and a blood sample for multiple clinical markers. Our primary objectives were to estimate the prevalence of EE, characterize the clinical profile and iron status indicators of subjects with EE, and describe subject-specific traits associated with EE. Overall prevalence of EE was 4.5% (95% CI, 3.3%-6.0%). Oxygen saturation was significantly lower among EE than non-EE group subjects (85.3% vs 90.1%, P < .001) but no difference was found in iron status indicators between both groups (P > .09 for all values). In multivariable logistic regression, we found that age ≥ 65 years (OR = 2.45, 95% CI, 1.16-5.09), male sex (3.86, 1.78-9.08), having metabolic syndrome (2.66, 1.27-5.75) or being overweight (5.20, 1.95-16.77), pulse oximetry < 85% (14.90, 6.43-34.90), and % predicted FVC < 80% (13.62, 4.40-41.80) were strongly associated with EE. Attributable fractions for EE were greatest for being overweight (26.7%), followed by male sex (21.5%), pulse oximetry < 85% (16.4%), having metabolic syndrome (14.4%), and % predicted FVC < 80% (9.3%). We found a lower prevalence of EE than in previous reports in the Peruvian Andes. Although the presence of hypoxemia and decreased vital capacity were strongly associated with excessive erythrocytosis, being overweight or having metabolic syndrome were associated with an important fraction of cases in our study population.

Prevalence, Clinical Profile, Iron Status, and Subject-Specific Traits for Excessive Erythrocytosis in Andean Adults Living Permanently at 3,825 Meters Above Sea Level

PubMed Central

De Ferrari, Aldo; Miranda, J. Jaime; Gilman, Robert H.; Dávila-Román, Victor G.; León-Velarde, Fabiola; Rivera-Ch, Maria; Huicho, Luis; Bernabé-Ortiz, Antonio; Wise, Robert A.

2014-01-01

BACKGROUND: Excessive erythrocytosis (EE) is a prevalent condition in populations living at high altitudes (> 2,500 m above sea level). Few large population-based studies have explored the association between EE and multiple subject-specific traits including oxygen saturation, iron status indicators, and pulmonary function. METHODS: We enrolled a sex-stratified and age-stratified sample of 1,065 high-altitude residents aged ≥ 35 years from Puno, Peru (3,825 m above sea level) and conducted a standardized questionnaire and physical examination that included spirometry, pulse oximetry, and a blood sample for multiple clinical markers. Our primary objectives were to estimate the prevalence of EE, characterize the clinical profile and iron status indicators of subjects with EE, and describe subject-specific traits associated with EE. RESULTS: Overall prevalence of EE was 4.5% (95% CI, 3.3%-6.0%). Oxygen saturation was significantly lower among EE than non-EE group subjects (85.3% vs 90.1%, P < .001) but no difference was found in iron status indicators between both groups (P > .09 for all values). In multivariable logistic regression, we found that age ≥ 65 years (OR = 2.45, 95% CI, 1.16-5.09), male sex (3.86, 1.78-9.08), having metabolic syndrome (2.66, 1.27-5.75) or being overweight (5.20, 1.95-16.77), pulse oximetry < 85% (14.90, 6.43-34.90), and % predicted FVC < 80% (13.62, 4.40-41.80) were strongly associated with EE. Attributable fractions for EE were greatest for being overweight (26.7%), followed by male sex (21.5%), pulse oximetry < 85% (16.4%), having metabolic syndrome (14.4%), and % predicted FVC < 80% (9.3%). CONCLUSIONS: We found a lower prevalence of EE than in previous reports in the Peruvian Andes. Although the presence of hypoxemia and decreased vital capacity were strongly associated with excessive erythrocytosis, being overweight or having metabolic syndrome were associated with an important fraction of cases in our study population. PMID

Global and Regional Estimates of Prevalent and Incident Herpes Simplex Virus Type 1 Infections in 2012

PubMed Central

Looker, Katharine J.; Magaret, Amalia S.; May, Margaret T.; Turner, Katherine M. E.; Vickerman, Peter; Gottlieb, Sami L.; Newman, Lori M.

2015-01-01

Background Herpes simplex virus type 1 (HSV-1) commonly causes orolabial ulcers, while HSV-2 commonly causes genital ulcers. However, HSV-1 is an increasing cause of genital infection. Previously, the World Health Organization estimated the global burden of HSV-2 for 2003 and for 2012. The global burden of HSV-1 has not been estimated. Methods We fitted a constant-incidence model to pooled HSV-1 prevalence data from literature searches for 6 World Health Organization regions and used 2012 population data to derive global numbers of 0-49-year-olds with prevalent and incident HSV-1 infection. To estimate genital HSV-1, we applied values for the proportion of incident infections that are genital. Findings We estimated that 3709 million people (range: 3440–3878 million) aged 0–49 years had prevalent HSV-1 infection in 2012 (67%), with highest prevalence in Africa, South-East Asia and Western Pacific. Assuming 50% of incident infections among 15-49-year-olds are genital, an estimated 140 million (range: 67–212 million) people had prevalent genital HSV-1 infection, most of which occurred in the Americas, Europe and Western Pacific. Conclusions The global burden of HSV-1 infection is huge. Genital HSV-1 burden can be substantial but varies widely by region. Future control efforts, including development of HSV vaccines, should consider the epidemiology of HSV-1 in addition to HSV-2, and especially the relative contribution of HSV-1 to genital infection. PMID:26510007

A meta-regression analysis of 41 Australian problem gambling prevalence estimates and their relationship to total spending on electronic gaming machines.

PubMed

Markham, Francis; Young, Martin; Doran, Bruce; Sugden, Mark

2017-05-23

Many jurisdictions regularly conduct surveys to estimate the prevalence of problem gambling in their adult populations. However, the comparison of such estimates is problematic due to methodological variations between studies. Total consumption theory suggests that an association between mean electronic gaming machine (EGM) and casino gambling losses and problem gambling prevalence estimates may exist. If this is the case, then changes in EGM losses may be used as a proxy indicator for changes in problem gambling prevalence. To test for this association this study examines the relationship between aggregated losses on electronic gaming machines (EGMs) and problem gambling prevalence estimates for Australian states and territories between 1994 and 2016. A Bayesian meta-regression analysis of 41 cross-sectional problem gambling prevalence estimates was undertaken using EGM gambling losses, year of survey and methodological variations as predictor variables. General population studies of adults in Australian states and territory published before 1 July 2016 were considered in scope. 41 studies were identified, with a total of 267,367 participants. Problem gambling prevalence, moderate-risk problem gambling prevalence, problem gambling screen, administration mode and frequency threshold were extracted from surveys. Administrative data on EGM and casino gambling loss data were extracted from government reports and expressed as the proportion of household disposable income lost. Money lost on EGMs is correlated with problem gambling prevalence. An increase of 1% of household disposable income lost on EGMs and in casinos was associated with problem gambling prevalence estimates that were 1.33 times higher [95% credible interval 1.04, 1.71]. There was no clear association between EGM losses and moderate-risk problem gambling prevalence estimates. Moderate-risk problem gambling prevalence estimates were not explained by the models (I 2  ≥ 0.97; R 2  ≤ 0.01). The

Who perpetrates violence against children? A systematic analysis of age-specific and sex-specific data

PubMed Central

Devries, Karen; Knight, Louise; Petzold, Max; Merrill, Katherine G; Maxwell, Lauren; Williams, Abigail; Cappa, Claudia; Chan, Ko Ling; Garcia-Moreno, Claudia; Hollis, NaTasha; Kress, Howard; Peterman, Amber; Walsh, Sophie D; Kishor, Sunita; Guedes, Alessandra; Bott, Sarah; Butron Riveros, Betzabe C; Watts, Charlotte; Abrahams, Naeemah

2018-01-01

Objective The epidemiology of violence against children is likely to differ substantially by sex and age of the victim and the perpetrator. Thus far, investment in effective prevention strategies has been hindered by lack of clarity in the burden of childhood violence across these dimensions. We produced the first age-specific and sex-specific prevalence estimates by perpetrator type for physical, sexual and emotional violence against children globally. Design We used random effects meta-regression to estimate prevalence. Estimates were adjusted for relevant quality covariates, variation in definitions of violence and weighted by region-specific, age-specific and sex-specific population data to ensure estimates reflect country population structures. Data sources Secondary data from 600 population or school-based representative datasets and 43 publications obtained via systematic literature review, representing 13 830 estimates from 171 countries. Eligibility criteria for selecting studies Estimates for recent violence against children aged 0–19 were included. Results The most common perpetrators of physical and emotional violence for both boys and girls across a range of ages are household members, with prevalence often surpassing 50%, followed by student peers. Children reported experiencing more emotional than physical violence from both household members and students. The most common perpetrators of sexual violence against girls aged 15–19 years are intimate partners; however, few data on other perpetrators of sexual violence against children are systematically collected internationally. Few age-specific and sex-specific data are available on violence perpetration by schoolteachers; however, existing data indicate high prevalence of physical violence from teachers towards students. Data from other authority figures, strangers, siblings and other adults are limited, as are data on neglect of children. Conclusions Without further investment in data

Who perpetrates violence against children? A systematic analysis of age-specific and sex-specific data.

PubMed

Devries, Karen; Knight, Louise; Petzold, Max; Merrill, Katherine G; Maxwell, Lauren; Williams, Abigail; Cappa, Claudia; Chan, Ko Ling; Garcia-Moreno, Claudia; Hollis, NaTasha; Kress, Howard; Peterman, Amber; Walsh, Sophie D; Kishor, Sunita; Guedes, Alessandra; Bott, Sarah; Butron Riveros, Betzabe C; Watts, Charlotte; Abrahams, Naeemah

2018-01-01

The epidemiology of violence against children is likely to differ substantially by sex and age of the victim and the perpetrator. Thus far, investment in effective prevention strategies has been hindered by lack of clarity in the burden of childhood violence across these dimensions. We produced the first age-specific and sex-specific prevalence estimates by perpetrator type for physical, sexual and emotional violence against children globally. We used random effects meta-regression to estimate prevalence. Estimates were adjusted for relevant quality covariates, variation in definitions of violence and weighted by region-specific, age-specific and sex-specific population data to ensure estimates reflect country population structures. Secondary data from 600 population or school-based representative datasets and 43 publications obtained via systematic literature review, representing 13 830 estimates from 171 countries. Estimates for recent violence against children aged 0-19 were included. The most common perpetrators of physical and emotional violence for both boys and girls across a range of ages are household members, with prevalence often surpassing 50%, followed by student peers. Children reported experiencing more emotional than physical violence from both household members and students. The most common perpetrators of sexual violence against girls aged 15-19 years are intimate partners; however, few data on other perpetrators of sexual violence against children are systematically collected internationally. Few age-specific and sex-specific data are available on violence perpetration by schoolteachers; however, existing data indicate high prevalence of physical violence from teachers towards students. Data from other authority figures, strangers, siblings and other adults are limited, as are data on neglect of children. Without further investment in data generation on violence exposure from multiple perpetrators for boys and girls of all ages, progress

Estimation of prognosis and prevalence of retinitis pigmentosa and Usher syndrome in Norway.

PubMed

Grøndahl, J

1987-04-01

Retinitis pigmentosa was diagnosed in 101 persons from 53 families. The prognosis for visual function was most favourable for the autosomal dominant group (38 patients from 8 families). The autosomal recessive group (40 patients from 25 families) and the 19 solitary cases were very heterogeneous, with prognosis ranging from favourable to very bad. There was a higher intrafamiliar correlation in the autosomal recessive than in the autosomal dominant group. In 28 patients from 18 families with Usher syndrome, almost all had good visual function until 30 years of age, and few had useful visual function after the age of 50. The age when the patients were registered varied between the different genetic types of retinitis pigmentosa, reflecting differences in prognosis. Therefore, ascertainment probability and prevalence were calculated for each genetic group separately. The prevalence of retinitis pigmentosa in Norway, all genetic groups included, was calculated to be 1/4440, the autosomal dominant type of the disease being the most frequent. The prevalence of Usher syndrome was calculated to be 3.6/100,000. Both retinitis pigmentosa and Usher syndrome were more prevalent in Laps.

Estimating Prevalence of Overweight or Obese Children and Adolescents in Small Geographic Areas Using Publicly Available Data

PubMed Central

Davila-Payan, Carlo; DeGuzman, Michael; Johnson, Kevin; Serban, Nicoleta

2015-01-01

Introduction Interventions for pediatric obesity can be geographically targeted if high-risk populations can be identified. We developed an approach to estimate the percentage of overweight or obese children aged 2 to 17 years in small geographic areas using publicly available data. We piloted our approach for Georgia. Methods We created a logistic regression model to estimate the individual probability of high body mass index (BMI), given data on the characteristics of the survey participants. We combined the regression model with a simulation to sample subpopulations and obtain prevalence estimates. The models used information from the 2001–2010 National Health and Nutrition Examination Survey, the 2010 Census, and the 2010 American Community Survey. We validated our results by comparing 1) estimates for adults in Georgia produced by using our approach with estimates from the Centers for Disease Control and Prevention (CDC) and 2) estimates for children in Arkansas produced by using our approach with school examination data. We generated prevalence estimates for census tracts in Georgia and prioritized areas for interventions. Results In DeKalb County, the mean prevalence among census tracts varied from 27% to 40%. For adults, the median difference between our estimates and CDC estimates was 1.3 percentage points; for Arkansas children, the median difference between our estimates and examination-based estimates data was 1.7 percentage points. Conclusion Prevalence estimates for census tracts can be different from estimates for the county, so small-area estimates are crucial for designing effective interventions. Our approach validates well against external data, and it can be a relevant aid for planning local interventions for children. PMID:25764138

Body dysmorphic disorder in different settings: A systematic review and estimated weighted prevalence.

PubMed

Veale, David; Gledhill, Lucinda J; Christodoulou, Polyxeni; Hodsoll, John

2016-09-01

Our aim was to systematically review the prevalence of body dysmorphic disorder (BDD) in a variety of settings. Weighted prevalence estimate and 95% confidence intervals in each study were calculated. The weighted prevalence of BDD in adults in the community was estimated to be 1.9%; in adolescents 2.2%; in student populations 3.3%; in adult psychiatric inpatients 7.4%; in adolescent psychiatric inpatients 7.4%; in adult psychiatric outpatients 5.8%; in general cosmetic surgery 13.2%; in rhinoplasty surgery 20.1%; in orthognathic surgery 11.2%; in orthodontics/cosmetic dentistry settings 5.2%; in dermatology outpatients 11.3%; in cosmetic dermatology outpatients 9.2%; and in acne dermatology clinics 11.1%. Women outnumbered men in the majority of settings but not in cosmetic or dermatological settings. BDD is common in some psychiatric and cosmetic settings but is poorly identified. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gambling disorder: estimated prevalence rates and risk factors in Macao.

PubMed

Wu, Anise M S; Lai, Mark H C; Tong, Kwok-Kit

2014-12-01

An excessive, problematic gambling pattern has been regarded as a mental disorder in the Diagnostic and Statistical Manual for Mental Disorders (DSM) for more than 3 decades (American Psychiatric Association [APA], 1980). In this study, its latest prevalence in Macao (one of very few cities with legalized gambling in China and the Far East) was estimated with 2 major changes in the diagnostic criteria, suggested by the 5th edition of DSM (APA, 2013): (a) removing the "Illegal Act" criterion, and (b) lowering the threshold for diagnosis. A random, representative sample of 1,018 Macao residents was surveyed with a phone poll design in January 2013. After the 2 changes were adopted, the present study showed that the estimated prevalence rate of gambling disorder was 2.1% of the Macao adult population. Moreover, the present findings also provided empirical support to the application of these 2 recommended changes when assessing symptoms of gambling disorder among Chinese community adults. Personal risk factors of gambling disorder, namely being male, having low education, a preference for casino gambling, as well as high materialism, were identified.

Group Sex and Prevalent Sexually Transmitted Infections Among Men Who Have Sex with Men.

PubMed

Rice, Cara E; Lynch, Courtney D; Norris, Alison H; Davis, John A; Fields, Karen S; Ervin, Melissa; Turner, Abigail Norris

2016-08-01

We evaluated the direct relation between group sex and prevalent sexually transmitted infections (STI) in a cross-sectional study of men who have sex with men (MSM) presenting at an urban STI clinic in the Midwestern US. Among 231 men who enrolled and reported that they have sex with men, we collected behavioral data using a combination of interviewer and self-administered surveys and extracted STI data from electronic health records. We used modified Poisson regression to examine the unadjusted and adjusted associations between group sex participation and prevalent STI. One-quarter of participants (n = 58) reported group sex participation in the last 3 months. Eighteen percent of participants (n = 42) had gonorrhea and 19 % (n = 45) had chlamydial infection. Men who reported recent group sex were more likely to be HIV-positive, to report recent drug use, and to report unprotected receptive anal intercourse in the past 3 months. After adjustment for age, race, and recent drug use, recent participation in group sex was associated with prevalent gonorrhea infection (prevalence ratio [PR] = 2.11, 95 % confidence interval [CI] = [1.13, 3.95]) but not chlamydia infection (PR = 1.03, 95 % CI = [0.58, 1.84]). We performed a sensitivity analysis in which we also adjusted for unprotected receptive anal intercourse and the results were not substantively changed. In summary, participation in group sex in the past 3 months was associated with a more than twofold increased prevalence of gonorrhea, but not with chlamydia. These findings support group sex participation as a potential contributor to increased STI prevalence.

Prevalence of Hippocampal Sclerosis in a Clinicopathologically Characterized Cohort.

PubMed

Malek-Ahmadi, Michael; Kahlon, Vickram; Adler, Charles H; Obradov, Aleksandra; Thind, Kabir; Shill, Holly A; Sue, Lucia I; Caviness, John N; Jacobson, Sandra; Sabbagh, Marwan N

2013-01-01

Hippocampal sclerosis (HS) is a neuropathological finding that frequently occurs with pathologies, such as Alzheimer's disease (AD). Prevalence estimates of HS in autopsy-confirmed dementia samples have varied between 0.4% and 24.5%. However, the prevalence of HS within other pathologic groups has not been well characterized. Utilizing a sample of 910 prospectively followed and clinicopathologically confirmed dementia cases, we determined the prevalence of HS among the sample and within specific pathologic groups. HS prevalence of the sample was compared to reported HS prevalence rates in other autopsy-confirmed dementia samples. The age range of the sample was 43 to 106 years, with a mean of 81.49±8.45. Of the 910 cases, 505 were male and 405 were female. For the entire sample, the average educational level was 14.59±2.65years. Of the 910 individuals, 47 (5.16%) cases had HS pathology present at autopsy. Among the 561 AD cases, 26 (4.43%) had HS pathology present. The frontotemporal dementia (FTD)/Pick's group had the highest percentage of cases with HS pathology (23.08%) followed by primary progressive aphasia (PPA) (16.67%) and Parkinson's disease with dementia (PDD) (5.34%). The HS prevalence rate of this study was not significantly different from all but 2 studies. The prevalence of HS pathology in this sample of autopsy-confirmed dementia cases was similar to other reported HS prevalence rates. This study is the first to report the presence of HS pathology in PDD cases.

Estimating Epilepsy Incidence and Prevalence in the US Pediatric Population Using Nationwide Health Insurance Claims Data.

PubMed

Kim, Hyunmi; Thurman, David J; Durgin, Tracy; Faught, Edward; Helmers, Sandra

2016-05-01

This study aims to determine prevalence and incidence of epilepsy in the US pediatric population. We analyzed commercial claims and Medicaid insurance claims data between 2008 and 2012. Over 8 million continuously enrolled lives aged 0 to 19 years were included. Our definition of a prevalent case of epilepsy was based on International Classification of Diseases-coded diagnoses of epilepsy or seizures and evidence of prescribed antiepileptic drugs. Incident cases were identified in subjects continuously enrolled for ≥2 years of which the first 2 years had no indication of epilepsy or seizures. The overall prevalence estimate for 2012 was 6.8 per 1,000 children. The overall incidence estimate for 2012 was 104 per 100,000 pediatric population. This study provides estimates of the prevalence and incidence of epilepsy in the US pediatric population, using large claims datasets from multiple US population sectors. The findings appear reasonably representative of the US-insured pediatric population. © The Author(s) 2015.

High Prevalence of Inadequate Calcium and Iron Intakes by Mexican Population Groups as Assessed by 24-Hour Recalls.

PubMed

Sánchez-Pimienta, Tania G; López-Olmedo, Nancy; Rodríguez-Ramírez, Sonia; García-Guerra, Armando; Rivera, Juan A; Carriquiry, Alicia L; Villalpando, Salvador

2016-09-01

A National Health and Nutrition Survey (ENSANUT) conducted in Mexico in 1999 identified a high prevalence of inadequate mineral intakes in the population by using 24-h recall questionnaires. However, the 1999 survey did not adjust for within-person variance. The 2012 ENSANUT implemented a more up-to-date 24-h recall methodology to estimate usual intake distributions and prevalence of inadequate intakes. We examined the distribution of usual intakes and prevalences of inadequate intakes of calcium, iron, magnesium, and zinc in the Mexican population in groups defined according to sex, rural or urban area, geographic region of residence, and socioeconomic status (SES). We used dietary intake data obtained through the 24-h recall automated multiple-pass method for 10,886 subjects as part of ENSANUT 2012. A second measurement on a nonconsecutive day was obtained for 9% of the sample. Distributions of usual intakes of the 4 minerals were obtained by using the Iowa State University method, and the prevalence of inadequacy was estimated by using the Institute of Medicine's Estimated Average Requirement cutoff. Calcium inadequacy was 25.6% in children aged 1-4 y and 54.5-88.1% in subjects >5 y old. More than 45% of subjects >5 y old had an inadequate intake of iron. Less than 5% of children aged <12 y and 25-35% of subjects aged >12 y had inadequate intakes of magnesium, whereas zinc inadequacy ranged from <10% in children aged <12 y to 21.6% in men aged ≥20 y. Few differences were found between rural and urban areas, regions, and tertiles of SES. Intakes of calcium, iron, magnesium, and zinc are inadequate in the Mexican population, especially among adolescents and adults. These results suggest a public health concern that must be addressed. © 2016 American Society for Nutrition.

[Prevalence of obesity, hypertension and dyslipidemia in rural aboriginal groups in Chile].

PubMed

Pérez, F; Carrasco, E; Santos, J L; Calvillán, M; Albala, C

1999-10-01

Chilean aboriginal ethnic groups (mapuche and aymaras) have a very low prevalence rate of type 2 diabetes. The investigation of a possible relationship between this low prevalence of diabetes and obesity, hypertension and serum lipid profiles in both groups is worthwhile. To study the prevalence of obesity, hypertension and lipid profile in two Chilean aboriginal communities. The prevalence of obesity, hypertension, fasting serum total cholesterol, HDL cholesterol, triglycerides, glucose, insulin, leptin and oral glucose tolerance test were measured in 345 mapuche (106 male) and 247 aymara (100 male) individuals. Sixty three percent of mapuche women, 37.9% of mapuche men, 39.7% of the aymara women and 27.0% of aymara men had a body mass index over 27 kg/m2. Twenty percent of mapuche men, 18.0% of mapuche women, 9.0% of aymara men and 4.8% of the aymara women had high blood pressure values. Serum HDL cholesterol was below 35 mg/dl in 16% of mapuche women, 14% of mapuche men, 25% of the aymara women and 27% of aymara men. No differences in total cholesterol levels were observed between mapuches and aymaras. Mapuche women have higher prevalence of obesity and high blood pressure than aymara women. Low serum HDL cholesterol has a higher prevalence among aymara individuals.

Training specificity and transfer in time and distance estimation.

PubMed

Healy, Alice F; Tack, Lindsay Anderson; Schneider, Vivian I; Barshi, Immanuel

2015-07-01

Learning is often specific to the conditions of training, making it important to identify which aspects of the testing environment are crucial to be matched in the training environment. In the present study, we examined training specificity in time and distance estimation tasks that differed only in the focus of processing (FOP). External spatial cues were provided for the distance estimation task and for the time estimation task in one condition, but not in another. The presence of a concurrent alphabet secondary task was manipulated during training and testing in all estimation conditions in Experiment 1. For distance as well as for time estimation in both conditions, training of the primary estimation task was found to be specific to the presence of the secondary task. In Experiments 2 and 3, we examined transfer between one estimation task and another, with no secondary task in either case. When all conditions were equal aside from the FOP instructions, including the presence of external spatial cues, Experiment 2 showed "transfer" between tasks, suggesting that training might not be specific to the FOP. When the external spatial cues were removed from the time estimation task, Experiment 3 showed no transfer between time and distance estimations, suggesting that external task cues influenced the procedures used in the estimation tasks.

Patient-specific dose estimation for pediatric chest CT

PubMed Central

Li, Xiang; Samei, Ehsan; Segars, W. Paul; Sturgeon, Gregory M.; Colsher, James G.; Frush, Donald P.

2008-01-01

Current methods for organ and effective dose estimations in pediatric CT are largely patient generic. Physical phantoms and computer models have only been developed for standard/limited patient sizes at discrete ages (e.g., 0, 1, 5, 10, 15years old) and do not reflect the variability of patient anatomy and body habitus within the same size/age group. In this investigation, full-body computer models of seven pediatric patients in the same size/protocol group (weight: 11.9–18.2kg) were created based on the patients’ actual multi-detector array CT (MDCT) data. Organs and structures in the scan coverage were individually segmented. Other organs and structures were created by morphing existing adult models (developed from visible human data) to match the framework defined by the segmented organs, referencing the organ volume and anthropometry data in ICRP Publication 89. Organ and effective dose of these patients from a chest MDCT scan protocol (64 slice LightSpeed VCT scanner, 120kVp, 70 or 75mA, 0.4s gantry rotation period, pitch of 1.375, 20mm beam collimation, and small body scan field-of-view) was calculated using a Monte Carlo program previously developed and validated to simulate radiation transport in the same CT system. The seven patients had normalized effective dose of 3.7–5.3mSv∕100mAs (coefficient of variation: 10.8%). Normalized lung dose and heart dose were 10.4–12.6mGy∕100mAs and 11.2–13.3mGy∕100mAs, respectively. Organ dose variations across the patients were generally small for large organs in the scan coverage (<7%), but large for small organs in the scan coverage (9%–18%) and for partially or indirectly exposed organs (11%–77%). Normalized effective dose correlated weakly with body weight (correlation coefficient:r=−0.80). Normalized lung dose and heart dose correlated strongly with mid-chest equivalent diameter (lung: r=−0.99, heart: r=−0.93); these strong correlation relationships can be used to estimate patient-specific

Patient-specific dose estimation for pediatric chest CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li Xiang; Samei, Ehsan; Segars, W. Paul

2008-12-15

Current methods for organ and effective dose estimations in pediatric CT are largely patient generic. Physical phantoms and computer models have only been developed for standard/limited patient sizes at discrete ages (e.g., 0, 1, 5, 10, 15 years old) and do not reflect the variability of patient anatomy and body habitus within the same size/age group. In this investigation, full-body computer models of seven pediatric patients in the same size/protocol group (weight: 11.9-18.2 kg) were created based on the patients' actual multi-detector array CT (MDCT) data. Organs and structures in the scan coverage were individually segmented. Other organs and structuresmore » were created by morphing existing adult models (developed from visible human data) to match the framework defined by the segmented organs, referencing the organ volume and anthropometry data in ICRP Publication 89. Organ and effective dose of these patients from a chest MDCT scan protocol (64 slice LightSpeed VCT scanner, 120 kVp, 70 or 75 mA, 0.4 s gantry rotation period, pitch of 1.375, 20 mm beam collimation, and small body scan field-of-view) was calculated using a Monte Carlo program previously developed and validated to simulate radiation transport in the same CT system. The seven patients had normalized effective dose of 3.7-5.3 mSv/100 mAs (coefficient of variation: 10.8%). Normalized lung dose and heart dose were 10.4-12.6 mGy/100 mAs and 11.2-13.3 mGy/100 mAs, respectively. Organ dose variations across the patients were generally small for large organs in the scan coverage (<7%), but large for small organs in the scan coverage (9%-18%) and for partially or indirectly exposed organs (11%-77%). Normalized effective dose correlated weakly with body weight (correlation coefficient: r=-0.80). Normalized lung dose and heart dose correlated strongly with mid-chest equivalent diameter (lung: r=-0.99, heart: r=-0.93); these strong correlation relationships can be used to estimate patient-specific organ

Prevalence of the β(S) gene among scheduled castes, scheduled tribes and other backward class groups in Central India.

PubMed

Shrikhande, Anuradha V; Arjunan, Aishwarya; Agarwal, Amit; Dani, Aarti; Tijare, Jayashri; Gettig, Elizabeth; Krishnamurti, Lakshmanan

2014-01-01

Sickle cell disease is an inherited disorder of the blood, and characterized by vasoocclusive crises (VOC), risks for pneumococcal infections and organ toxicities, is associated with morbidity and premature mortality. India, with a population of 1.2 billion individuals, is estimated to be home to over 50.0% of the world's patients with sickle cell disease. The β(S) gene [β6(A3)Glu→Val; HBB: c.20A>T] has the highest prevalence in three socio-economically disadvantaged ethnic categories: the Scheduled Castes (SC), the Scheduled Tribes (ST), and Other Backward Class (OBC) groups in India. The tradition of endogamy practiced by the ethnic groups in India provides the rationale for the screening of individual populations to better understand the distribution of the β(S) gene, guide counseling and awareness programs and aid development of public policy. We undertook a study to describe the prevalence of the β(S) gene in these ethnic groups in the district of Nagpur, Maharashtra in Central India. Through community screening and subsequent targeted screening of high risk individuals, 35,636 individuals were screened, of whom 5466 were found to have sickle cell trait and 1010 were identified with sickle cell disease. Community screening revealed a sickle cell trait prevalence of 13.0% in the SC, 12.0% in the ST and 3.4% in the OBC population. This study describes the prevalence of the β(S) gene within these groups in Central India determined by large scale community screening. This program has uncovered previously undiagnosed cases, provided detailed information to guide population-based disease counseling, prevention and comprehensive care programs.

Producer estimates of prevalence and perceived importance of lameness in dairy herds with tiestalls, freestalls, and automated milking systems.

PubMed

Cutler, J H Higginson; Rushen, J; de Passillé, A M; Gibbons, J; Orsel, K; Pajor, E; Barkema, H W; Solano, L; Pellerin, D; Haley, D; Vasseur, E

2017-12-01

Lameness is one of the most important welfare and productivity concerns in the dairy industry. Our objectives were to obtain producers' estimates of its prevalence and their perceptions of lameness, and to investigate how producers monitor lameness in tiestall (TS), freestall with milking parlor (FS), and automated milking system (AMS) herds. Forty focal cows per farm in 237 Canadian dairy herds were scored for lameness by trained researchers. On the same day, the producers completed a questionnaire. Mean herd-level prevalence of lameness estimated by producers was 9.0% (±0.9%; ±SE), whereas the researchers observed a mean prevalence of 22.2% (±0.9%). Correlation between producer- and researcher-estimated lameness prevalence was low (r = 0.19) and mean researcher prevalence was 1.6, 1.8, and 4.1 times higher in AMS, FS, and TS farms, respectively. A total of 48% of producers thought lameness was a moderate or major problem in their herds (TS = 34%; AMS =53%; FS = 59%). One third of producers considered lameness the highest ranked health problem they were trying to control, whereas two-thirds of producers (TS = 43%; AMS = 63%; FS = 71%) stated that they had made management changes to deal with lameness in the past 2 yr. Almost all producers (98%) stated they routinely check cows to identify new cases of lameness; however, 40% of producers did not keep records of lameness (AMS = 24%; FS = 23%; TS = 60%). A majority (69%) of producers treated lame cows themselves immediately after detection, whereas 13% relied on hoof-trimmer or veterinarians to plan treatment. Producers are aware of lameness as an issue in dairy herds and almost all monitor lameness as part of their daily routine. However, producers underestimate lameness prevalence, which highlights that lameness detection continues to be difficult in in all housing systems, especially in TS herds. Training to improve detection, record keeping, identification of farm-specific risk factors, and treatment planning

Prevalence and risk factors associated with Entamoeba histolytica/dispar/moshkovskii infection among three Orang Asli ethnic groups in Malaysia.

PubMed

Shahrul Anuar, Tengku; M Al-Mekhlafi, Hesham; Abdul Ghani, Mohamed Kamel; Osman, Emelia; Mohd Yasin, Azlin; Nordin, Anisah; Nor Azreen, Siti; Md Salleh, Fatmah; Ghazali, Nuraffini; Bernadus, Mekadina; Moktar, Norhayati

2012-01-01

Entamoeba histolytica/Entamoeba dispar/Entamoeba moshkovskii infection is still prevalent in rural Malaysia especially among Orang Asli communities. Currently, information on prevalence of this infection among different ethnic groups of Orang Asli is unavailable in Malaysia. To contribute to a better comprehension of the epidemiology of this infection, a cross-sectional study aimed at providing the first documented data on the prevalence and risk factors associated with E. histolytica/E. dispar/E. moshkovskii infection was carried out among three Orang Asli ethnic groups (Proto-Malay, Negrito, and Senoi) in selected villages in Negeri Sembilan, Perak, and Pahang states, Malaysia. Faecal samples were examined by formalin-ether sedimentation and trichrome staining techniques. Of 500 individuals, 8.7% (13/150) of Proto-Malay, 29.5% (41/139) of Negrito, and 18.5% (39/211) of Senoi were positive for E. histolytica/E. dispar/E. moshkovskii, respectively. The prevalence of this infection showed an age-dependency relationship, with higher rates observed among those aged less than 15 years in all ethnic groups studied. Multivariate analysis confirmed that not washing hands after playing with soils or gardening and presence of other family members infected with E. histolytica/E. dispar/E. moshkovskii were significant risk factors of infection among all ethnic groups. However, eating with hands, the consumption of raw vegetables, and close contact with domestic animals were identified as significant risk factors in Senoi. Essentially, the findings highlighted that E. histolytica/E. dispar/E. moshkovskii parasites are still prevalent in Malaysia. Further studies using molecular approaches to distinguish the morphologically identical species of pathogenic, E. histolytica from the non-pathogenic, E. dispar and E. moshkovskii are needed. The establishment of such data will be beneficial for the public health authorities in the planning and implementation of specific prevention

Why patients visit their doctors: assessing the most prevalent conditions in a defined American population.

PubMed

St Sauver, Jennifer L; Warner, David O; Yawn, Barbara P; Jacobson, Debra J; McGree, Michaela E; Pankratz, Joshua J; Melton, L Joseph; Roger, Véronique L; Ebbert, Jon O; Rocca, Walter A

2013-01-01

To describe the prevalence of nonacute conditions among patients seeking health care in a defined US population, emphasizing age, sex, and ethnic differences. The Rochester Epidemiology Project (REP) medical records linkage system was used to identify all residents of Olmsted County, Minnesota, on April 1, 2009, who had consented to review of their medical records for research (142,377 patients). We then electronically extracted all International Classification of Diseases, Ninth Revision codes noted in the records of these patients by any health care institution between January 1, 2005, and December 31, 2009. We grouped International Classification of Diseases, Ninth Revision codes into clinical classification codes and then into 47 broader disease groups associated with health-related quality of life. Age- and sex-specific prevalence was estimated by dividing the number of individuals within each group by the corresponding age- and sex-specific population. Patients within a group who had multiple codes were counted only once. We included a total of 142,377 patients, 75,512 (53%) of whom were female. Skin disorders (42.7%), osteoarthritis and joint disorders (33.6%), back problems (23.9%), disorders of lipid metabolism (22.4%), and upper respiratory tract disease (22.1%, excluding asthma) were the most prevalent disease groups in this population. Ten of the 15 most prevalent disease groups were more common in women in almost all age groups, whereas disorders of lipid metabolism, hypertension, and diabetes were more common in men. Additionally, the prevalence of 7 of the 10 most common groups increased with advancing age. Prevalence also varied across ethnic groups (whites, blacks, and Asians). Our findings suggest areas for focused research that may lead to better health care delivery and improved population health. Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Age-specific and sex-specific prevalence of cerebral β-amyloidosis, tauopathy, and neurodegeneration in cognitively unimpaired individuals aged 50-95 years: a cross-sectional study.

PubMed

Jack, Clifford R; Wiste, Heather J; Weigand, Stephen D; Therneau, Terry M; Knopman, David S; Lowe, Val; Vemuri, Prashanthi; Mielke, Michelle M; Roberts, Rosebud O; Machulda, Mary M; Senjem, Matthew L; Gunter, Jeffrey L; Rocca, Walter A; Petersen, Ronald C

2017-06-01

A new classification for biomarkers in Alzheimer's disease and cognitive ageing research is based on grouping the markers into three categories: amyloid deposition (A), tauopathy (T), and neurodegeneration or neuronal injury (N). Dichotomising these biomarkers as normal or abnormal results in eight possible profiles. We determined the clinical characteristics and prevalence of each ATN profile in cognitively unimpaired individuals aged 50 years and older. All participants were in the Mayo Clinic Study of Aging, a population-based study that uses a medical records linkage system to enumerate all individuals aged 50-89 years in Olmsted County, MN, USA. Potential participants are randomly selected, stratified by age and sex, and invited to participate in cognitive assessments; individuals without medical contraindications are invited to participate in brain imaging studies. Participants who were judged clinically as having no cognitive impairment and underwent multimodality imaging between Oct 11, 2006, and Oct 5, 2016, were included in the current study. Participants were classified as having normal (A-) or abnormal (A+) amyloid using amyloid PET, normal (T-) or abnormal (T+) tau using tau PET, and normal (N-) or abnormal (N+) neurodegeneration or neuronal injury using cortical thickness assessed by MRI. We used the cutoff points of standard uptake value ratio (SUVR) 1·42 (centiloid 19) for amyloid PET, 1·23 SUVR for tau PET, and 2·67 mm for MRI cortical thickness. Age-specific and sex-specific prevalences of the eight groups were determined using multinomial models combining data from 435 individuals with amyloid PET, tau PET, and MRI assessments, and 1113 individuals who underwent amyloid PET and MRI, but not tau PET imaging. The numbers of participants in each profile group were 165 A-T-N-, 35 A-T+N-, 63 A-T-N+, 19 A-T+N+, 44 A+T-N-, 25 A+T+N-, 35 A+T-N+, and 49 A+T+N+. Age differed by ATN group (p<0·0001), ranging from a median 58 years (IQR 55-64) in A

[Estimates of the prevalence of child malnutrition in Brazilian municipalities in 2006].

PubMed

Benício, Maria Helena D'Aquino; Martins, Ana Paula Bortoletto; Venancio, Sonia Isoyama; Barros, Aluísio Jardim Dornellas de

2013-06-01

To estimate the prevalence of malnutrition in children for all Brazilian municipalities. A multilevel logistic regression model was used to estimate the individual probability of malnutrition in 5,507 Brazilian municipalities in 2006, in terms of predictive factors grouped according to hierarchical levels. The response variable was child malnutrition (children aged from six to 59 months with height for age and sex below -2 z-scores, according to the World Health Organization standard). The predictive variables were determinants of malnutrition measured similarly by the National Demographics and Health Survey-2006 and the Sample from the 2000 Demographic Census. At level 1 (individual): sex and age, level 2 (household): socioeconomic variables, water and indoor plumbing, urban or rural area and level 3 (municipal): location of the municipality and coverage of the Family Health Strategy (FHS) in 2006. The study detected a statistically significant chance of malnutrition in male children, those living in households with two or more individuals per room, those belonging to the lowest quintiles of the socioeconomic score, those with three or more children under five in the household, those with no access to running water or located in the North. There was a negative dose-response association between FHS coverage and the chance of malnutrition (p = 0.007). FHS coverage in the municipality equal to or greater than 70% showed a 45% reduction in the chance of infant malnutrition. Estimates of the prevalence of child malnutrition show that most of the cities have the risk of malnutrition under control, very low or low. Risks of greater magnitude exist only in 158 municipalities in the North Region. Childhood malnutrition as a public health problem is concentrated in the cities of the North region, where FHS coverage is lower. A protective effect of FHS in relation to child malnutrition was found in the country as a whole, irrespective of other determinants of the problem.

Prevalence of myopia in a group of Hong Kong microscopists.

PubMed

Ting, Patrick W K; Lam, Carly S Y; Edwards, Marion H; Schmid, Katrina L

2004-02-01

To study the prevalence and magnitude of myopia in a group of Hong Kong Chinese microscopists and compare it with that observed in microscopists working in the United Kingdom. Forty-seven microscopists (36 women and 11 men) with a median age of 31 years and working in hospital laboratories throughout Hong Kong were recruited to the study. Information about past refractive corrections, microscopy work, and visual symptoms associated with microscope use were collected. All subjects had a comprehensive eye examination at The Hong Kong Polytechnic University Optometry Clinic, including measures of refractive error (both noncycloplegic and cycloplegic), binocular vision functions, and axial length. The prevalence of myopia in this group of microscopists was 87%, the mean (+/- SD) refractive error was -4.45 +/- 3.03 D and mean axial length was 25.13 +/- 1.52 mm. No correlation was found between refractive error and years spent working as a microscopist or number of hours per day spent performing microscopy. Subjects reporting myopia progression (N = 22) did not differ from the refractively stable group (N = 19) in terms of their microscopy working history, working hours, tonic accommodation level, or near phoria. However, the AC/A ratio of the progressing group was significantly greater than that of the stable group (4.59 delta/D cf. 3.34 delta/D). The myopia prevalence of Hong Kong Chinese microscopists was higher than that of microscopists in the United Kingdom (87% cf. 71%), as well as the Hong Kong general population (87% cf. 70%). The average amount of myopia was also higher in the Hong Kong Chinese microscopists than the Hong Kong general population (-4.45 D cf. -3.00 D). We have confirmed that the microscopy task may slightly exacerbate myopia development in Chinese people.

Nationwide survey on the organ-specific prevalence and its interaction with sarcoidosis in Japan.

PubMed

Hattori, Takeshi; Konno, Satoshi; Shijubo, Noriharu; Yamaguchi, Tetsuo; Sugiyama, Yukihiko; Honma, Sakae; Inase, Naohiko; Ito, Yoichi M; Nishimura, Masaharu

2018-06-21

Previous studies attempted to characterize the subjects with sarcoidosis according to differences in sex, age, and the presence of specific organ involvement. However, significant interactions among these factors precluded a clear conclusion based on simple comparison. This study aimed to clarify the age- and sex-stratified prevalence of specific organ involvement and the heterogenous nature of sarcoidosis. Using the data of 9,965 patients who were newly registered into a database at the Ministry of Health, Labour and Welfare, Japan between 2002 and 2011, we evaluated the age- and sex-specific prevalence of the eye, lung, and skin involvement of sarcoidosis. We also attempted corresponding analysis considering multiple factors. As compared with several decades ago, the monophasic age distribution in men became biphasic, and the biphasic distribution in women, monophasic. The prevalence of pulmonary and cutaneous lesions was significantly associated with age, whereas the prevalence of ocular involvement showed a biphasic pattern. The prevalence of bilateral hilar lymphadenopathy was significantly higher, whereas the prevalence of diffuse lung shadow was significantly lower, in subjects with ocular involvement than those without ocular involvement. Corresponding analysis visually clarified the complex interactions among factors. Our results contribute to a better understanding of the heterogeneous features of sarcoidosis.

Factors associated with suicidal ideation and attempts in Spain for different age groups. Prevalence before and after the onset of the economic crisis.

PubMed

Miret, Marta; Caballero, Francisco Félix; Huerta-Ramírez, Raúl; Moneta, María Victoria; Olaya, Beatriz; Chatterji, Somnath; Haro, Josep Maria; Ayuso-Mateos, José Luis

2014-07-01

Little is known about whether the prevalence of suicidal ideation and attempts has changed in the wake of the economic crisis. The aim of this study was to estimate current prevalence of suicidal ideation and attempts in the general population in Spain, to compare it with the prevalence found before the economic crisis, and to analyse the factors associated with suicidality in different age groups. A total of 4583 non-institutionalised adults were interviewed in a cross-sectional household survey of a nationally representative sample in Spain. Several modules of an adapted version of the Composite International Diagnostic Interview were administered to the participants, and logistic regression models were employed in each age group. Lifetime prevalence of suicidal ideation and attempts in Spain were respectively, 3.67% and 1.46%. Mental disorders presented the highest significant effects on lifetime suicidal ideation. Marital status, heavy alcohol consumption, and occupational status were associated with lifetime suicidal ideation in people aged 18-49, whereas loneliness was associated with the 50-64 group, and financial problems with the 65+ group. A younger age, poor health status and the presence of depression were all associated with lifetime suicide attempts. The cross-sectional design of the study represents a methodological limitation. The current prevalence of suicidal ideation and attempts in Spain is similar to the one found ten years ago, before the recent economic crisis. The factors associated with suicidality vary among age groups. Suicide prevention programmes should focus on early detection and prevention for depression and anxiety disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

Sytematic review and meta-analysis of prevalence of hepatitis B in India.

PubMed

Batham, Ashish; Narula, Dherian; Toteja, Tanmay; Sreenivas, V; Puliyel, Jacob M

2007-09-01

To evaluate the point prevalence of Hepatitis B in India. Meta-analysis of data on point prevalence from different parts of the country. Searches were made in Medline, Cochrane Library and Best bets and previous reviews. A limited hand search of cross references was also done. Finally a consultation with experts was held to enlarge the references base. Studies reporting prevalence of HBsAg were selected. Data from high risk groups were excluded. 54 papers reporting data on 61 populations were identified. The true prevalence for each study was calculated from the reported prevalence using the specificity and sensitivity of the test employed. The true prevalence in non-tribal populations is 2.4% (95% CI: 2.2%-2.7%). True prevalence among tribal populations is 15.9% (CI: 11.4%-20.4%). These figures may be useful in estimation of the burden of the disease in the country and for projecting the cost-benefits of immunization.

Patient-specific dose estimation for pediatric abdomen-pelvis CT

NASA Astrophysics Data System (ADS)

Li, Xiang; Samei, Ehsan; Segars, W. Paul; Sturgeon, Gregory M.; Colsher, James G.; Frush, Donald P.

2009-02-01

The purpose of this study is to develop a method for estimating patient-specific dose from abdomen-pelvis CT examinations and to investigate dose variation across patients in the same weight group. Our study consisted of seven pediatric patients in the same weight/protocol group, for whom full-body computer models were previously created based on the patients' CT data obtained for clinical indications. Organ and effective dose of these patients from an abdomen-pelvis scan protocol (LightSpeed VCT scanner, 120-kVp, 85-90 mA, 0.4-s gantry rotation period, 1.375-pitch, 40-mm beam collimation, and small body scan field-of-view) was calculated using a Monte Carlo program previously developed and validated for the same CT system. The seven patients had effective dose of 2.4-2.8 mSv, corresponding to normalized effective dose of 6.6-8.3 mSv/100mAs (coefficient of variation: 7.6%). Dose variations across the patients were small for large organs in the scan coverage (mean: 6.6%; range: 4.9%-9.2%), larger for small organs in the scan coverage (mean: 10.3%; range: 1.4%-15.6%), and the largest for organs partially or completely outside the scan coverage (mean: 14.8%; range: 5.7%-27.7%). Normalized effective dose correlated strongly with body weight (correlation coefficient: r = -0.94). Normalized dose to the kidney and the adrenal gland correlated strongly with mid-liver equivalent diameter (kidney: r = -0.97; adrenal glands: r = -0.98). Normalized dose to the small intestine correlated strongly with mid-intestine equivalent diameter (r = -0.97). These strong correlations suggest that patient-specific dose may be estimated for any other child in the same size group who undergoes the abdomen-pelvis scan.

Estimation After a Group Sequential Trial.

PubMed

Milanzi, Elasma; Molenberghs, Geert; Alonso, Ariel; Kenward, Michael G; Tsiatis, Anastasios A; Davidian, Marie; Verbeke, Geert

2015-10-01

Group sequential trials are one important instance of studies for which the sample size is not fixed a priori but rather takes one of a finite set of pre-specified values, dependent on the observed data. Much work has been devoted to the inferential consequences of this design feature. Molenberghs et al (2012) and Milanzi et al (2012) reviewed and extended the existing literature, focusing on a collection of seemingly disparate, but related, settings, namely completely random sample sizes, group sequential studies with deterministic and random stopping rules, incomplete data, and random cluster sizes. They showed that the ordinary sample average is a viable option for estimation following a group sequential trial, for a wide class of stopping rules and for random outcomes with a distribution in the exponential family. Their results are somewhat surprising in the sense that the sample average is not optimal, and further, there does not exist an optimal, or even, unbiased linear estimator. However, the sample average is asymptotically unbiased, both conditionally upon the observed sample size as well as marginalized over it. By exploiting ignorability they showed that the sample average is the conventional maximum likelihood estimator. They also showed that a conditional maximum likelihood estimator is finite sample unbiased, but is less efficient than the sample average and has the larger mean squared error. Asymptotically, the sample average and the conditional maximum likelihood estimator are equivalent. This previous work is restricted, however, to the situation in which the the random sample size can take only two values, N = n or N = 2 n . In this paper, we consider the more practically useful setting of sample sizes in a the finite set { n 1 , n 2 , …, n L }. It is shown that the sample average is then a justifiable estimator , in the sense that it follows from joint likelihood estimation, and it is consistent and asymptotically unbiased. We also show why

Prevalence, Formation, Maintenance, and Evaluation of Interdisciplinary Student Aging Interest Groups

ERIC Educational Resources Information Center

Jones, Katherine J.; Vandenberg, Edward V.; Bottsford, Lisa

2011-01-01

The authors describe the prevalence, formation, maintenance, and evaluation of student aging interest groups. They conducted a cross-sectional electronic survey of the 46 academic medical centers funded by the Donald W. Reynolds Foundation. To evaluate their group of approximately 50 students, the authors conducted an electronic pretest and…

Study Heterogeneity and Estimation of Prevalence of Primary Aldosteronism: A Systematic Review and Meta-Regression Analysis.

PubMed

Käyser, Sabine C; Dekkers, Tanja; Groenewoud, Hans J; van der Wilt, Gert Jan; Carel Bakx, J; van der Wel, Mark C; Hermus, Ad R; Lenders, Jacques W; Deinum, Jaap

2016-07-01

For health care planning and allocation of resources, realistic estimation of the prevalence of primary aldosteronism is necessary. Reported prevalences of primary aldosteronism are highly variable, possibly due to study heterogeneity. Our objective was to identify and explain heterogeneity in studies that aimed to establish the prevalence of primary aldosteronism in hypertensive patients. PubMed, EMBASE, Web of Science, Cochrane Library, and reference lists from January 1, 1990, to January 31, 2015, were used as data sources. Description of an adult hypertensive patient population with confirmed diagnosis of primary aldosteronism was included in this study. Dual extraction and quality assessment were the forms of data extraction. Thirty-nine studies provided data on 42 510 patients (nine studies, 5896 patients from primary care). Prevalence estimates varied from 3.2% to 12.7% in primary care and from 1% to 29.8% in referral centers. Heterogeneity was too high to establish point estimates (I(2) = 57.6% in primary care; 97.1% in referral centers). Meta-regression analysis showed higher prevalences in studies 1) published after 2000, 2) from Australia, 3) aimed at assessing prevalence of secondary hypertension, 4) that were retrospective, 5) that selected consecutive patients, and 6) not using a screening test. All studies had minor or major flaws. This study demonstrates that it is pointless to claim low or high prevalence of primary aldosteronism based on published reports. Because of the significant impact of a diagnosis of primary aldosteronism on health care resources and the necessary facilities, our findings urge for a prevalence study whose design takes into account the factors identified in the meta-regression analysis.

Prevalence of scientific misconduct among a group of researchers in Nigeria.

PubMed

Okonta, Patrick; Rossouw, Theresa

2013-12-01

There is a dearth of information on the prevalence of scientific misconduct from Nigeria. This study aimed at determining the prevalence of scientific misconduct in a group of researchers in Nigeria. Factors associated with the prevalence were ascertained. A descriptive study of researchers who attended a scientific conference in 2010 was conducted using the adapted Scientific Misconduct Questionnaire-Revised (SMQ-R). Ninety-one researchers (68.9%) admitted having committed at least one of the eight listed forms of scientific misconduct. Disagreement about authorship was the most common form of misconduct committed (36.4%) while plagiarism was the least (9.2%). About 42% of researchers had committed falsification of data or plagiarism. Analysis of specific acts of misconduct showed that committing plagiarism was inversely associated with years in research (Fisher exact p-value = 0.02); falsifying data was related to perceived low effectiveness of the institution's rules and procedures for reducing scientific misconduct (X(2) = 6.44, p-value = 0.01); and succumbing to pressure from study sponsor to engage in unethical practice was related to sex of researcher (Fisher exact p-value = 0.02). The emergent data from this study is a cause for serious concern and calls for prompt intervention. The best response to reducing scientific misconduct will proceed from measures that contain both elements of prevention and enforcement. Training on research ethics has to be integrated into the curriculum of undergraduate and postgraduate students while provision should be made for in-service training of researchers. Penalties against acts of scientific misconduct should be enforced at institutional and national levels. © 2012 John Wiley & Sons Ltd.

PREVALENCE OF SCIENTIFIC MISCONDUCT AMONG A GROUP OF RESEARCHERS IN NIGERIA

PubMed Central

OKONTA, PATRICK; ROSSOUW, THERESA

2012-01-01

Background There is a dearth of information on the prevalence of scientific misconduct from Nigeria. Objectives This study aimed at determining the prevalence of scientific misconduct in a group of researchers in Nigeria. Factors associated with the prevalence were ascertained. Method A descriptive study of researchers who attended a scientific conference in 2010 was conducted using the adapted Scientific Misconduct Questionnaire- Revised (SMQ-R). Results Ninety-one researchers (68.9%) admitted having committed at least one of the eight listed forms of scientific misconduct. Disagreement about authorship was the most common form of misconduct committed (36.4%) while plagiarism was the least (9.2%). About 42% of researchers had committed falsification of data or plagiarism. Analysis of specific acts of misconduct showed that committing plagiarism was inversely associated with years in research (Fisher exact p-value = 0.02); falsifying data was related to perceived low effectiveness of the institution’s rules and procedures for reducing scientific misconduct (X2 = 6.44, p-value = 0.01); and succumbing to pressure from study sponsor to engage in unethical practice was related to sex of researcher (Fisher exact p-value = 0.02). Conclusions The emergent data from this study is a cause for serious concern and calls for prompt intervention. The best response to reducing scientific misconduct will proceed from measures that contain both elements of prevention and enforcement. Training on research ethics has to be integrated into the curriculum of undergraduate and postgraduate students while provision should be made for in-service training of researchers. Penalties against acts of scientific misconduct should be enforced at institutional and national levels. PMID:22994914

Accounting for imperfect detection of groups and individuals when estimating abundance.

PubMed

Clement, Matthew J; Converse, Sarah J; Royle, J Andrew

2017-09-01

If animals are independently detected during surveys, many methods exist for estimating animal abundance despite detection probabilities <1. Common estimators include double-observer models, distance sampling models and combined double-observer and distance sampling models (known as mark-recapture-distance-sampling models; MRDS). When animals reside in groups, however, the assumption of independent detection is violated. In this case, the standard approach is to account for imperfect detection of groups, while assuming that individuals within groups are detected perfectly. However, this assumption is often unsupported. We introduce an abundance estimator for grouped animals when detection of groups is imperfect and group size may be under-counted, but not over-counted. The estimator combines an MRDS model with an N-mixture model to account for imperfect detection of individuals. The new MRDS-Nmix model requires the same data as an MRDS model (independent detection histories, an estimate of distance to transect, and an estimate of group size), plus a second estimate of group size provided by the second observer. We extend the model to situations in which detection of individuals within groups declines with distance. We simulated 12 data sets and used Bayesian methods to compare the performance of the new MRDS-Nmix model to an MRDS model. Abundance estimates generated by the MRDS-Nmix model exhibited minimal bias and nominal coverage levels. In contrast, MRDS abundance estimates were biased low and exhibited poor coverage. Many species of conservation interest reside in groups and could benefit from an estimator that better accounts for imperfect detection. Furthermore, the ability to relax the assumption of perfect detection of individuals within detected groups may allow surveyors to re-allocate resources toward detection of new groups instead of extensive surveys of known groups. We believe the proposed estimator is feasible because the only additional field data

Accounting for imperfect detection of groups and individuals when estimating abundance

USGS Publications Warehouse

Clement, Matthew J.; Converse, Sarah J.; Royle, J. Andrew

2017-01-01

If animals are independently detected during surveys, many methods exist for estimating animal abundance despite detection probabilities <1. Common estimators include double-observer models, distance sampling models and combined double-observer and distance sampling models (known as mark-recapture-distance-sampling models; MRDS). When animals reside in groups, however, the assumption of independent detection is violated. In this case, the standard approach is to account for imperfect detection of groups, while assuming that individuals within groups are detected perfectly. However, this assumption is often unsupported. We introduce an abundance estimator for grouped animals when detection of groups is imperfect and group size may be under-counted, but not over-counted. The estimator combines an MRDS model with an N-mixture model to account for imperfect detection of individuals. The new MRDS-Nmix model requires the same data as an MRDS model (independent detection histories, an estimate of distance to transect, and an estimate of group size), plus a second estimate of group size provided by the second observer. We extend the model to situations in which detection of individuals within groups declines with distance. We simulated 12 data sets and used Bayesian methods to compare the performance of the new MRDS-Nmix model to an MRDS model. Abundance estimates generated by the MRDS-Nmix model exhibited minimal bias and nominal coverage levels. In contrast, MRDS abundance estimates were biased low and exhibited poor coverage. Many species of conservation interest reside in groups and could benefit from an estimator that better accounts for imperfect detection. Furthermore, the ability to relax the assumption of perfect detection of individuals within detected groups may allow surveyors to re-allocate resources toward detection of new groups instead of extensive surveys of known groups. We believe the proposed estimator is feasible because the only additional field data

Prevalence and type distribution of human papillomavirus (HPV) in Malaysian women with and without cervical cancer: an updated estimate.

PubMed

Tan, Shing Cheng; Ismail, Mohd Pazudin; Duski, Daniel Roza; Othman, Nor Hayati; Ankathil, Ravindran

2018-04-27

Information on the prevalence and type distribution of human papillomavirus (HPV) among Malaysian women is currently limited. The present study therefore aimed to provide an updated estimate on the prevalence and type distribution of HPV among Malaysian women with and without cervical cancer. Total DNA was isolated from the cervical cell specimens of 185 histopathologically confirmed cervical cancer patients and 209 cancer-free healthy females who were tested negative in a recent Pap test. Viral-specific DNA was subsequently amplified with biotinylated primers and hybridized to HPV type-specific probes via a proprietary "flow-through hybridization" process for determination of HPV genotype. It was demonstrated that 83.2% of the cervical cancer patients and none (0.0%) of the cancer-free females were positive for HPV infection. Among HPV-positive subjects, 14 different viral genotypes were observed, namely HPV16, 18, 31, 33, 35, 45, 52, 53, 58, 66/68, 73, 81, 82, and 84/26. A total of 91.6% of the HPV-positive subjects had single-type HPV infections and the remaining 8.4% were simultaneously infected by two HPV genotypes. The most common HPV infections found were HPV16 (35.7%), HPV18 (26.0%), HPV58 (9.1%), and HPV33 (7.1%) single-type infections, followed by HPV16 + HPV18 co-infections (5.2%). The study has successfully provided an updated estimate on the prevalence and type distribution of HPV among Malaysian women with and without cervical cancer. These findings could contribute valuable information for appraisal of the impact and cost-effectiveness of prophylactic HPV vaccines in the Malaysian population. © 2018 The Author(s).

Estimating prevalence trends in adult gonorrhoea and syphilis in low- and middle-income countries with the Spectrum-STI model: results for Zimbabwe and Morocco from 1995 to 2016.

PubMed

Korenromp, Eline L; Mahiané, Guy; Rowley, Jane; Nagelkerke, Nico; Abu-Raddad, Laith; Ndowa, Francis; El-Kettani, Amina; El-Rhilani, Houssine; Mayaud, Philippe; Chico, R Matthew; Pretorius, Carel; Hecht, Kendall; Wi, Teodora

2017-12-01

To develop a tool for estimating national trends in adult prevalence of sexually transmitted infections by low- and middle-income countries, using standardised, routinely collected programme indicator data. The Spectrum-STI model fits time trends in the prevalence of active syphilis through logistic regression on prevalence data from antenatal clinic-based surveys, routine antenatal screening and general population surveys where available, weighting data by their national coverage and representativeness. Gonorrhoea prevalence was fitted as a moving average on population surveys (from the country, neighbouring countries and historic regional estimates), with trends informed additionally by urethral discharge case reports, where these were considered to have reasonably stable completeness. Prevalence data were adjusted for diagnostic test performance, high-risk populations not sampled, urban/rural and male/female prevalence ratios, using WHO's assumptions from latest global and regional-level estimations. Uncertainty intervals were obtained by bootstrap resampling. Estimated syphilis prevalence (in men and women) declined from 1.9% (95% CI 1.1% to 3.4%) in 2000 to 1.5% (1.3% to 1.8%) in 2016 in Zimbabwe, and from 1.5% (0.76% to 1.9%) to 0.55% (0.30% to 0.93%) in Morocco. At these time points, gonorrhoea estimates for women aged 15-49 years were 2.5% (95% CI 1.1% to 4.6%) and 3.8% (1.8% to 6.7%) in Zimbabwe; and 0.6% (0.3% to 1.1%) and 0.36% (0.1% to 1.0%) in Morocco, with male gonorrhoea prevalences 14% lower than female prevalence. This epidemiological framework facilitates data review, validation and strategic analysis, prioritisation of data collection needs and surveillance strengthening by national experts. We estimated ongoing syphilis declines in both Zimbabwe and Morocco. For gonorrhoea, time trends were less certain, lacking recent population-based surveys. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted

True versus Apparent Malaria Infection Prevalence: The Contribution of a Bayesian Approach

PubMed Central

Claes, Filip; Van Hong, Nguyen; Torres, Kathy; Mao, Sokny; Van den Eede, Peter; Thi Thinh, Ta; Gamboa, Dioni; Sochantha, Tho; Thang, Ngo Duc; Coosemans, Marc; Büscher, Philippe; D'Alessandro, Umberto; Berkvens, Dirk; Erhart, Annette

2011-01-01

Aims To present a new approach for estimating the “true prevalence” of malaria and apply it to datasets from Peru, Vietnam, and Cambodia. Methods Bayesian models were developed for estimating both the malaria prevalence using different diagnostic tests (microscopy, PCR & ELISA), without the need of a gold standard, and the tests' characteristics. Several sources of information, i.e. data, expert opinions and other sources of knowledge can be integrated into the model. This approach resulting in an optimal and harmonized estimate of malaria infection prevalence, with no conflict between the different sources of information, was tested on data from Peru, Vietnam and Cambodia. Results Malaria sero-prevalence was relatively low in all sites, with ELISA showing the highest estimates. The sensitivity of microscopy and ELISA were statistically lower in Vietnam than in the other sites. Similarly, the specificities of microscopy, ELISA and PCR were significantly lower in Vietnam than in the other sites. In Vietnam and Peru, microscopy was closer to the “true” estimate than the other 2 tests while as expected ELISA, with its lower specificity, usually overestimated the prevalence. Conclusions Bayesian methods are useful for analyzing prevalence results when no gold standard diagnostic test is available. Though some results are expected, e.g. PCR more sensitive than microscopy, a standardized and context-independent quantification of the diagnostic tests' characteristics (sensitivity and specificity) and the underlying malaria prevalence may be useful for comparing different sites. Indeed, the use of a single diagnostic technique could strongly bias the prevalence estimation. This limitation can be circumvented by using a Bayesian framework taking into account the imperfect characteristics of the currently available diagnostic tests. As discussed in the paper, this approach may further support global malaria burden estimation initiatives. PMID:21364745

Questionnaire layout and wording influence prevalence and risk estimates of respiratory symptoms in a population cohort

PubMed Central

Ekerljung, Linda; Rönmark, Eva; Lötvall, Jan; Wennergren, Göran; Torén, Kjell; Lundbäck, Bo

2013-01-01

Objective Results of epidemiological studies are greatly influenced by the chosen methodology. The study aims to investigate how two frequently used questionnaires (Qs), with partly different layout, influence the prevalence of respiratory symptoms. Study Design and Setting A booklet containing two Qs, the Global Allergy and Asthma European Network Q and the Obstructive Lung Disease in Northern Sweden Q, was mailed to 30 000 subjects aged 16–75 years in West Sweden; 62% responded. Sixteen questions were included in the analysis: seven identical between the Qs, four different in set-up and five with the same layout but different wording. Comparisons were made using differences in proportions, observed agreement and Kappa statistics. Results Identical questions yielded similar prevalences with high observed agreement and kappa values. Questions with different set-up or differences in wording resulted in significantly different prevalences with lower observed agreement and kappa values. In general, the use of follow-up questions, excluding subjects answering no to the initial question, resulted in 2.9–6.7% units lower prevalence. Conclusion The question set-up has great influences on epidemiological results, and specifically questions that are set up to be excluded based on a previous no answer leads to lower prevalence compared with detached questions. Therefore, Q layout and exact wording of questions has to be carefully considered when comparing studies. Please cite this paper as: Ekerljung L, Rönmark E, Lötvall J, Wennergren G, Torén K and Lundbäck B. Questionnaire layout and wording influence prevalence and risk estimates of respiratory symptoms in a population cohort. Clin Respir J 2013; 7: 53–63. PMID:22243692

Educational Disparities in the Burden of Disability: Contributions of Disease Prevalence and Disabling Impact

PubMed Central

Nusselder, Wilma J.; Looman, Caspar W.; Mackenbach, Johan P.

2014-01-01

Objectives. We assessed the contributions of the prevalence and disabling impact of specific diseases to educational disparities in the prevalence of disability. Methods. We examined a large representative survey of the Dutch population, the Dutch Permanent Survey of Living Conditions (2001–2007; n = 24 883; ages 40–97 years). We attributed the prevalence of disability to chronic diseases by using their empirical associations and assuming independent competing causes of disability. We estimated contributions of prevalence and the disabling impact of diseases to disparities in disability using counterfactuals. Results. We found that the prevalence of disability in individuals with only an elementary education was 19 to 20 percentage points higher than that in individuals with tertiary education. Sixty-five percent of this difference could be attributed to specific chronic diseases, but more so to their disabling impact (49%–51%) than to their prevalence (20%–29%). Back pain, neck or arm conditions, and peripheral vascular disease contributed most to the disparity in men, and arthritis, back pain, and chronic nonspecific lung disease contributed most to the disparity in women. Conclusions. Educational disparities in the burden of disability were primarily caused by high disabling impacts of chronic diseases among low educated groups. Tackling disparities might require more effective treatment or rehabilitation of disability in lower socioeconomic groups. PMID:24922134

Urbanization and prevalence of type 2 diabetes in Southern Asia: A systematic analysis

PubMed Central

Cheema, Arsalan; Adeloye, Davies; Sidhu, Simrita; Sridhar, Devi; Chan, Kit Yee

2014-01-01

Background Diabetes mellitus is one of the diseases considered to be the main constituents of the global non–communicable disease (NCD) pandemic. Despite the large impact that NCDs are predicted to have, particularly in developing countries, estimates of disease burden are sparse and inconsistent. This systematic review transparently estimates prevalence of type 2 diabetes mellitus in Southern Asia, its association with urbanization and provides insight into the policy challenges facing the region. Methods The databases Medline and PubMed were searched for population–based studies providing estimates of diabetes prevalence in the Southern Asia region. Studies using WHO diagnostic criteria of fasting plasma glucose (FPG) ≥7.0mmol/L and/or 2h–plasma glucose (2hPG) ≥11.1mmol/L were included. Data from eligible studies was extracted into bubble graphs, and trend lines were applied to UNPD figures to estimate age–specific prevalence in the regional population. Estimates specific to sex, area of residency, and diagnostic method were compared and trends analysed. Results A total of 151 age–specific prevalence estimates were extracted from 39 studies. Diabetes prevalence was estimated to be 7.47% for 2005 and 7.60% for 2010. Prevalence was strongly associated with increased age, male gender and urban residency (P < 0.001). Conclusion Diabetes prevalence in Southern Asia is high and predicted to increase in the future as life expectancy rises and the region continues to urbanise. Countries in this region need to improve NCD surveillance and monitoring so policies can be informed with the best evidence. Programs for prevention need to be put in place, and health system capacity and access needs to be assessed and increased to deal with the predicted rise in NCD prevalence. PMID:24976963

Estimation of true height: a study in population-specific methods among young South African adults.

PubMed

Lahner, Christen Renée; Kassier, Susanna Maria; Veldman, Frederick Johannes

2017-02-01

To investigate the accuracy of arm-associated height estimation methods in the calculation of true height compared with stretch stature in a sample of young South African adults. A cross-sectional descriptive design was employed. Pietermaritzburg, Westville and Durban, KwaZulu-Natal, South Africa, 2015. Convenience sample (N 900) aged 18-24 years, which included an equal number of participants from both genders (150 per gender) stratified across race (Caucasian, Black African and Indian). Continuous variables that were investigated included: (i) stretch stature; (ii) total armspan; (iii) half-armspan; (iv) half-armspan ×2; (v) demi-span; (vi) demi-span gender-specific equation; (vii) WHO equation; and (viii) WHO-adjusted equations; as well as categorization according to gender and race. Statistical analysis was conducted using IBM SPSS Statistics Version 21.0. Significant correlations were identified between gender and height estimation measurements, with males being anatomically larger than females (P<0·001). Significant differences were documented when study participants were stratified according to race and gender (P<0·001). Anatomical similarities were noted between Indians and Black Africans, whereas Caucasians were anatomically different from the other race groups. Arm-associated height estimation methods were able to estimate true height; however, each method was specific to each gender and race group. Height can be calculated by using arm-associated measurements. Although universal equations for estimating true height exist, for the enhancement of accuracy, the use of equations that are race-, gender- and population-specific should be considered.

The Future Prevalence of Sarcopenia in Europe: A Claim for Public Health Action.

PubMed

Ethgen, O; Beaudart, C; Buckinx, F; Bruyère, O; Reginster, J Y

2017-03-01

Sarcopenia is a major public health issue. To convince health policy makers of the emergency to invest in the sarcopenia field, it is of critical importance to produce reliable figures of the expected burden of sarcopenia in the coming years. Age- and gender-specific population projections were retrieved until 2045 from the Eurostat online database (28 European countries). Age- and gender-specific prevalences of sarcopenia were interpolated from a study that compared prevalence estimates according to the different diagnostic cutoffs of the EWGSOP proposed definition. The reported prevalence estimates were interpolated between 65 and 100 years. Interpolated age- and gender-specific estimates of sarcopenia prevalence were then applied to population projections until 2045. Using the definition providing the lowest prevalence estimates, the number of individuals with sarcopenia would rise in Europe from 10,869,527 in 2016 to 18,735,173 in 2045 (a 72.4% increase). This corresponds to an overall prevalence of sarcopenia in the elderly rising from 11.1% in 2016 to 12.9% in 2045. With the definition providing the highest prevalence estimates, the number of individuals with sarcopenia would rise from 19,740,527 in 2016 to 32,338,990 in 2045 (a 63.8% increase), corresponding to overall prevalence rates in the elderly of 20.2% and 22.3% for 2016 and 2045, respectively. We showed that the number of sarcopenic patients will dramatically increase in the next 30 years, making consequences of muscle wasting a major public health issue.

Estimating the incidence, prevalence and true cost of asthma in the UK: secondary analysis of national stand-alone and linked databases in England, Northern Ireland, Scotland and Wales-a study protocol.

PubMed

Mukherjee, Mome; Gupta, Ramyani; Farr, Angela; Heaven, Martin; Stoddart, Andrew; Nwaru, Bright I; Fitzsimmons, Deborah; Chamberlain, George; Bandyopadhyay, Amrita; Fischbacher, Colin; Dibben, Christopher; Shields, Michael; Phillips, Ceri; Strachan, David; Davies, Gwyneth; McKinstry, Brian; Sheikh, Aziz

2014-11-04

Asthma is now one of the most common long-term conditions in the UK. It is therefore important to develop a comprehensive appreciation of the healthcare and societal costs in order to inform decisions on care provision and planning. We plan to build on our earlier estimates of national prevalence and costs from asthma by filling the data gaps previously identified in relation to healthcare and broadening the field of enquiry to include societal costs. This work will provide the first UK-wide estimates of the costs of asthma. In the context of asthma for the UK and its member countries (ie, England, Northern Ireland, Scotland and Wales), we seek to: (1) produce a detailed overview of estimates of incidence, prevalence and healthcare utilisation; (2) estimate health and societal costs; (3) identify any remaining information gaps and explore the feasibility of filling these and (4) provide insights into future research that has the potential to inform changes in policy leading to the provision of more cost-effective care. Secondary analyses of data from national health surveys, primary care, prescribing, emergency care, hospital, mortality and administrative data sources will be undertaken to estimate prevalence, healthcare utilisation and outcomes from asthma. Data linkages and economic modelling will be undertaken in an attempt to populate data gaps and estimate costs. Separate prevalence and cost estimates will be calculated for each of the UK-member countries and these will then be aggregated to generate UK-wide estimates. Approvals have been obtained from the NHS Scotland Information Services Division's Privacy Advisory Committee, the Secure Anonymised Information Linkage Collaboration Review System, the NHS South-East Scotland Research Ethics Service and The University of Edinburgh's Centre for Population Health Sciences Research Ethics Committee. We will produce a report for Asthma-UK, submit papers to peer-reviewed journals and construct an interactive map

Estimating CHD prevalence by small area: integrating information from health surveys and area mortality.

PubMed

Congdon, Peter

2008-03-01

The risk of coronary heart disease (CHD) is strongly linked both to deprivation and ethnicity and so prevalence will vary considerably between areas. Variations in prevalence are important in assessing health care needs and how far CHD service provision and surgical intervention rates match need. This paper uses a regression model of prevalence rates by age, sex, region and ethnicity from the 1999 and 2003 Health Surveys for England to estimate CHD prevalence for 354 English local authority areas. To allow for the impact of social factors on prevalence, survey information on the deprivation quintile in the respondents' micro-area of residence is also used. Allowance is also made for area CHD mortality rates (obtained from aggregated vital statistics data) which are positively correlated with, and hence a proxy for, CHD prevalence rates. An application involves assessment of surgical intervention rates in relation to prevalence at the level of 28 Strategic Health Authorities.

Usher syndrome: definition and estimate of prevalence from two high-risk populations.

PubMed

Boughman, J A; Vernon, M; Shaver, K A

1983-01-01

The Usher Syndrome (US) refers to the combined neurosensory deficits of profound hearing impairment and retinitis pigmentosa. We have obtained information on 600 cases of deaf-blindness from the registry of the Helen Keller National Center for Deaf-Blind Youths and Adults (HKNC). Of these, 54% met the diagnostic criteria of US, although only 23.8% were so diagnosed. More extensive analysis of 189 Usher clients from HKNC showed an excess of males, some variability in audiograms, and wide ophthalmologic variation. Genetic analysis of 113 sibships showed a segregation ratio consistent with recessive inheritance. The Acadian population of Louisiana has a high frequency of US which contributes significantly to the deaf population of the state. Among 48 cases from the Louisiana School for the Deaf, there was an excess of males, more variability in audiograms than expected, and an increased segregation ratio in the 26 informative sibships. Estimates of prevalence obtained using registry data and statistics from Louisiana clearly suggest that the previous estimate of 2.4 per 100,000 is too low for the United States. Recognizing problems with ascertainment, our prevalence estimate of 4.4 per 100,000 is still considered quite conservative.

The prevalence and incidence of active syphilis in women in Morocco, 1995-2016: Model-based estimation and implications for STI surveillance.

PubMed

Bennani, Aziza; El-Kettani, Amina; Hançali, Amina; El-Rhilani, Houssine; Alami, Kamal; Youbi, Mohamed; Rowley, Jane; Abu-Raddad, Laith; Smolak, Alex; Taylor, Melanie; Mahiané, Guy; Stover, John; Korenromp, Eline L

2017-01-01

Evolving health priorities and resource constraints mean that countries require data on trends in sexually transmitted infections (STI) burden, to inform program planning and resource allocation. We applied the Spectrum STI estimation tool to estimate the prevalence and incidence of active syphilis in adult women in Morocco over 1995 to 2016. The results from the analysis are being used to inform Morocco's national HIV/STI strategy, target setting and program evaluation. Syphilis prevalence levels and trends were fitted through logistic regression to data from surveys in antenatal clinics, women attending family planning clinics and other general adult populations, as available post-1995. Prevalence data were adjusted for diagnostic test performance, and for the contribution of higher-risk populations not sampled in surveys. Incidence was inferred from prevalence by adjusting for the average duration of infection with active syphilis. In 2016, active syphilis prevalence was estimated to be 0.56% in women 15 to 49 years of age (95% confidence interval, CI: 0.3%-1.0%), and around 21,675 (10,612-37,198) new syphilis infections have occurred. The analysis shows a steady decline in prevalence from 1995, when the prevalence was estimated to be 1.8% (1.0-3.5%). The decline was consistent with decreasing prevalences observed in TB patients, fishermen and prisoners followed over 2000-2012 through sentinel surveillance, and with a decline since 2003 in national HIV incidence estimated earlier through independent modelling. Periodic population-based surveys allowed Morocco to estimate syphilis prevalence and incidence trends. This first-ever undertaking engaged and focused national stakeholders, and confirmed the still considerable syphilis burden. The latest survey was done in 2012 and so the trends are relatively uncertain after 2012. From 2017 Morocco plans to implement a system to record data from routine antenatal programmatic screening, which should help update and re

Estimating prevalence of functional iron deficiency anaemia in advanced cancer.

PubMed

Neoh, Karen; Stanworth, Simon; Pasricha, Sant-Rayn; Bennett, Michael I

2017-04-01

Anaemia is a common complication of cancer causing symptoms including fatigue. It is also associated with shorter survival. Cancer causes systemic inflammation which interrupts iron metabolism leading to a functional iron deficiency (FID). There are few data on prevalence or aetiology of anaemia in those with advanced cancer. We aimed to establish the prevalence of anaemia and estimate extent of FID anaemia in patients with advanced cancer. All patients with advanced cancer referred to two UK specialist palliative care services over 1 year were identified. Demographic and clinical data were linked with routinely collected haematological and biochemical profiles. We assessed the numbers of patients with abnormal values for haemoglobin, % hypochromic red cells (>5% indicates iron-restricted erythropoiesis) and CRP (>10 indicates systemic inflammation). We judged that FID anaemia was likely when patients had all three abnormalities and ferritin 30-800 ng/ml. Out of 2416 patients, 1797 had a cancer diagnosis and laboratory data available. Mean haemoglobin was 116 g/l. Sixty-three percent of patients were anaemic, mild 25%, moderate 35% and severe 3%. Women had significantly higher mean haemoglobin than men, and there was wide variation in anaemia prevalence across tumour sites. Thirty-nine percent of patients who had all four parameters checked met our criteria for FID anaemia. There were significant relationships between haemoglobin, % hypochromic red cells and CRP (p = 0.0001). Anaemia was common in this population, and we estimate this was caused by FID in 66% of anaemic patients. Further research is needed to validate our diagnostic criteria before this approach can be used in clinical practice.

GROUP B STREPTOCOCCUS: PREVALENCE IN A NON-OBSTETRIC POPULATION

PubMed Central

LECLAIR, Catherine M.; HART, Ashley E.; GOETSCH, Martha F.; CARPENTIER, Heather; JENSEN, Jeffrey T.

2010-01-01

Objective: To establish and compare the prevalence of Group B streptococcus (GBS) colonization in the vaginas of non-obstetric women with and without vaginitis. Materials and Methods: Cross-sectional analysis Group B streptococcus vaginal culture status of non-pregnant, estrogen-replete women ≥18 years presenting for annual gynecological exams or vaginal infection. Subjects were classified into 3 groups: no vaginitis (NV) if symptoms were absent and exam was normal, common vaginitis (CV) if microscopic exam revealed yeast, bacterial vaginosis or trichomonads, or inflammatory vaginitis (IV) if exam revealed inflammation and immature squamous cells, but no pathogens. Results: Of the 215 women recruited: 147 (68.4%) showed no evidence of vaginitis, 41 (19.1%) had CV, and 27 (12.6%) showed evidence of IV. The overall prevalence rate of GBS was 22.8%. Vaginitis was associated with a significantly increased risk of GBS colonization [Adjusted OR: CV 2.7 (1.1-6.2); IV 2.9 (1.1-8.0)]. Logistic regression revealed pH >4.5, presence of abnormal discharge on exam and a women's complaint of current symptoms to be significant predicators of the presence of GBS. Conclusion: GBS colonization occurs more commonly in women with vaginitis. This suggests that disruption of the normal vaginal bacterial environment is an important predictor for GBS colonization. PMID:20592549

The 2005 Workbook: an improved tool for estimating HIV prevalence in countries with low level and concentrated epidemics.

PubMed

Lyerla, R; Gouws, E; García-Calleja, J M; Zaniewski, E

2006-06-01

This paper describes improvements and updates to an established approach to making epidemiological estimates of HIV prevalence in countries with low level and concentrated epidemics. The structure of the software used to make estimates is briefly described, with particular attention to changes and improvements. The approach focuses on identifying populations which, through their behaviour, are at high risk of infection with HIV or who are exposed through the risk behaviour of their sexual partners. Estimates of size and HIV prevalence of these populations allow the total number of HIV infected people in a country or region to be estimated. Major changes in the software focus on the move away from short term projections and towards developing an epidemiological curve that more accurately represents the change in prevalence of HIV over time. The software continues to provide an output file for use in the Spectrum software so as to estimate the demographic impact of HIV infection at country level.

Prevalence of myopia in an adult population of two different ethnic groups in the Ecuadorian Amazon.

PubMed

Jiménez, José Ramón; Bermúdez, Javier; Rubiño, Manuel; Gómez, Luis; Anera, Rosario González

2004-01-01

To determine the prevalence of myopia in the adult populations of two different ethnic communities in the Ecuadorian Amazon. Refraction with retinoscopy after cycloplegia was performed for 507 Naporuna (an ethnic group indigenous to the jungles of the Ecuadorian Amazon) and for 776 settlers (white-mestizos from the Andes, now living in the Amazon and working for the petroleum industry). Ages ranged from 18 to 45 years. All subjects had little or no formal education. The prevalence of myopia was 4.7% among the Naporuna and 5.5% among the settlers; the prevalence of hyperopia was higher, at 17.8% and 36.0%, respectively. The prevalence of myopia in the two communities studied agrees with the results of other studies showing a low prevalence of myopia among groups with low levels of formal education or groups living a nonurban lifestyle.

Group vector space method for estimating enthalpy of vaporization of organic compounds at the normal boiling point.

PubMed

Wenying, Wei; Jinyu, Han; Wen, Xu

2004-01-01

The specific position of a group in the molecule has been considered, and a group vector space method for estimating enthalpy of vaporization at the normal boiling point of organic compounds has been developed. Expression for enthalpy of vaporization Delta(vap)H(T(b)) has been established and numerical values of relative group parameters obtained. The average percent deviation of estimation of Delta(vap)H(T(b)) is 1.16, which show that the present method demonstrates significant improvement in applicability to predict the enthalpy of vaporization at the normal boiling point, compared the conventional group methods.

Reliability of Nationwide Prevalence Estimates of Dementia: A Critical Appraisal Based on Brazilian Surveys

PubMed Central

2015-01-01

Background The nationwide dementia prevalence is usually calculated by applying the results of local surveys to countries’ populations. To evaluate the reliability of such estimations in developing countries, we chose Brazil as an example. We carried out a systematic review of dementia surveys, ascertained their risk of bias, and present the best estimate of occurrence of dementia in Brazil. Methods and Findings We carried out an electronic search of PubMed, Latin-American databases, and a Brazilian thesis database for surveys focusing on dementia prevalence in Brazil. The systematic review was registered at PROSPERO (CRD42014008815). Among the 35 studies found, 15 analyzed population-based random samples. However, most of them utilized inadequate criteria for diagnostics. Six studies without these limitations were further analyzed to assess the risk of selection, attrition, outcome and population bias as well as several statistical issues. All the studies presented moderate or high risk of bias in at least two domains due to the following features: high non-response, inaccurate cut-offs, and doubtful accuracy of the examiners. Two studies had limited external validity due to high rates of illiteracy or low income. The three studies with adequate generalizability and the lowest risk of bias presented a prevalence of dementia between 7.1% and 8.3% among subjects aged 65 years and older. However, after adjustment for accuracy of screening, the best available evidence points towards a figure between 15.2% and 16.3%. Conclusions The risk of bias may strongly limit the generalizability of dementia prevalence estimates in developing countries. Extrapolations that have already been made for Brazil and Latin America were based on a prevalence that should have been adjusted for screening accuracy or not used at all due to severe bias. Similar evaluations regarding other developing countries are needed in order to verify the scope of these limitations. PMID:26131563

Prevalence and Risk Factors Associated with Entamoeba histolytica/dispar/moshkovskii Infection among Three Orang Asli Ethnic Groups in Malaysia

PubMed Central

Shahrul Anuar, Tengku; M. Al-Mekhlafi, Hesham; Abdul Ghani, Mohamed Kamel; Osman, Emelia; Mohd Yasin, Azlin; Nordin, Anisah; Nor Azreen, Siti; Md Salleh, Fatmah; Ghazali, Nuraffini; Bernadus, Mekadina; Moktar, Norhayati

2012-01-01

Background Entamoeba histolytica/Entamoeba dispar/Entamoeba moshkovskii infection is still prevalent in rural Malaysia especially among Orang Asli communities. Currently, information on prevalence of this infection among different ethnic groups of Orang Asli is unavailable in Malaysia. To contribute to a better comprehension of the epidemiology of this infection, a cross-sectional study aimed at providing the first documented data on the prevalence and risk factors associated with E. histolytica/E. dispar/E. moshkovskii infection was carried out among three Orang Asli ethnic groups (Proto-Malay, Negrito, and Senoi) in selected villages in Negeri Sembilan, Perak, and Pahang states, Malaysia. Methods/Findings Faecal samples were examined by formalin-ether sedimentation and trichrome staining techniques. Of 500 individuals, 8.7% (13/150) of Proto-Malay, 29.5% (41/139) of Negrito, and 18.5% (39/211) of Senoi were positive for E. histolytica/E. dispar/E. moshkovskii, respectively. The prevalence of this infection showed an age-dependency relationship, with higher rates observed among those aged less than 15 years in all ethnic groups studied. Multivariate analysis confirmed that not washing hands after playing with soils or gardening and presence of other family members infected with E. histolytica/E. dispar/E. moshkovskii were significant risk factors of infection among all ethnic groups. However, eating with hands, the consumption of raw vegetables, and close contact with domestic animals were identified as significant risk factors in Senoi. Conclusions Essentially, the findings highlighted that E. histolytica/E. dispar/E. moshkovskii parasites are still prevalent in Malaysia. Further studies using molecular approaches to distinguish the morphologically identical species of pathogenic, E. histolytica from the non-pathogenic, E. dispar and E. moshkovskii are needed. The establishment of such data will be beneficial for the public health authorities in the planning and

Population aging, macroeconomic changes, and global diabetes prevalence, 1990-2008.

PubMed

Sudharsanan, Nikkil; Ali, Mohammed K; Mehta, Neil K; Narayan, K M Venkat

2015-01-01

Diabetes is an important contributor to global morbidity and mortality. The contributions of population aging and macroeconomic changes to the growth in diabetes prevalence over the past 20 years are unclear. We used cross-sectional data on age- and sex-specific counts of people with diabetes by country, national population estimates, and country-specific macroeconomic variables for the years 1990, 2000, and 2008. Decomposition analysis was performed to quantify the contribution of population aging to the change in global diabetes prevalence between 1990 and 2008. Next, age-standardization was used to estimate the contribution of age composition to differences in diabetes prevalence between high-income (HIC) and low-to-middle-income countries (LMICs). Finally, we used non-parametric correlation and multivariate first-difference regression estimates to examine the relationship between macroeconomic changes and the change in diabetes prevalence between 1990 and 2008. Globally, diabetes prevalence grew by two percentage points between 1990 (7.4 %) and 2008 (9.4 %). Population aging was responsible for 19 % of the growth, with 81 % attributable to increases in the age-specific prevalences. In both LMICs and HICs, about half the growth in age-specific prevalences was from increasing levels of diabetes between ages 45-65 (51 % in HICs and 46 % in LMICs). After age-standardization, the difference in the prevalence of diabetes between LMICs and HICs was larger (1.9 % point difference in 1990; 1.5 % point difference in 2008). We found no evidence that macroeconomic changes were associated with the growth in diabetes prevalence. Population aging explains a minority of the recent growth in global diabetes prevalence. The increase in global diabetes between 1990 and 2008 was primarily due to an increase in the prevalence of diabetes at ages 45-65. We do not find evidence that basic indicators of economic growth, development, globalization, or urbanization were related

VARIATION IN THE GROUP-SPECIFIC CARBOHYDRATE OF GROUP A STREPTOCOCCI

PubMed Central

McCarty, Maclyn

1956-01-01

Soil organisms have been isolated which elaborate induced enzymes capable of attacking group A and variant (V) streptococcal carbohydrates. The V enzyme hydrolyzes V carbohydrate extensively to dialyzable split products with resultant total loss of precipitating activity with homologous antisera. The split products inhibit the reaction between intact V carbohydrate and its antiserum: evidence is presented which indicates that rhamnose oligosaccharides are responsible for the inhibitory effect. The serological specificity of the V carbohydrate thus appears to be primarily dependent on a rhamnose-rhamnose linkage. The effect of the A enzyme on A carbohydrate is characterized by the removal of 50 to 70 per cent of the total glucosamine in the form of free N-acetyl-glucosamine. As a result of this treatment, the residual carbohydrate loses its reactivity with specific group A antisera and at the same time develops markedly increased cross-reactivity with V antisera. This cross-reactivity is in turn eliminated by treatment with V enzyme. The evidence suggests that the specificity of group A carbohydrate is determined to a large extent by side chains of N-acetyl-glucosamine which also serve to mask underlying rhamnose-rhamnose linkages with V specificity. PMID:13367334

The prevalence of bad headaches including migraine in a multiethnic community.

PubMed

Thomson, A N; White, G E; West, R

1993-11-10

Overall and ethnic specific prevalences of bad headache including migraine, for the New Zealand population, are unknown. A study was carried out in South Auckland to estimate prevalence and to explore ethnic differences in doctor attendance for the diagnosis and management of bad headaches. Telephone interviews were administered to respondents selected by random digit dialing of households. 40.6% of the respondents suffered from bad headaches. 54.5% of these had the characteristics of bad headache with features symptomatic of migraine. Trends in the prevalence of bad headache with features symptomatic of common migraine, peaked between the ages of 30-49 years in both men and women. A difference was seen in the prevalence of bad headache with aura, with or without common migraine features, when ethnic groups and gender were examined. The difference in prevalence of aura was particularly noticeable between Pacific Island men and women. Although there was no difference between ethnic groups in doctor attendance, headaches were more likely to be labelled as migraine in Europeans than in the Polynesian groups. Ways in which people perceive and report their bad headaches have a bearing on management by general practitioners. Although no overall ethnic predominance was seen, there was a gender difference amongst Pacific Island people in reporting bad headaches with aura. The labelling process, and thus the management by general practitioners does demonstrate likely ethnic differences.

Prevalence Estimation of Protected Health Information in Swedish Clinical Text.

PubMed

Henriksson, Aron; Kvist, Maria; Dalianis, Hercules

2017-01-01

Obscuring protected health information (PHI) in the clinical text of health records facilitates the secondary use of healthcare data in a privacy-preserving manner. Although automatic de-identification of clinical text using machine learning holds much promise, little is known about the relative prevalence of PHI in different types of clinical text and whether there is a need for domain adaptation when learning predictive models from one particular domain and applying it to another. In this study, we address these questions by training a predictive model and using it to estimate the prevalence of PHI in clinical text written (1) in different clinical specialties, (2) in different types of notes (i.e., under different headings), and (3) by persons in different professional roles. It is demonstrated that the overall PHI density is 1.57%; however, substantial differences exist across domains.

Econometric estimation of country-specific hospital costs.

PubMed

Adam, Taghreed; Evans, David B; Murray, Christopher JL

2003-02-26

Information on the unit cost of inpatient and outpatient care is an essential element for costing, budgeting and economic-evaluation exercises. Many countries lack reliable estimates, however. WHO has recently undertaken an extensive effort to collect and collate data on the unit cost of hospitals and health centres from as many countries as possible; so far, data have been assembled from 49 countries, for various years during the period 1973-2000. The database covers a total of 2173 country-years of observations. Large gaps remain, however, particularly for developing countries. Although the long-term solution is that all countries perform their own costing studies, the question arises whether it is possible to predict unit costs for different countries in a standardized way for short-term use. The purpose of the work described in this paper, a modelling exercise, was to use the data collected across countries to predict unit costs in countries for which data are not yet available, with the appropriate uncertainty intervals.The model presented here forms part of a series of models used to estimate unit costs for the WHO-CHOICE project. The methods and the results of the model, however, may be used to predict a number of different types of country-specific unit costs, depending on the purpose of the exercise. They may be used, for instance, to estimate the costs per bed-day at different capacity levels; the "hotel" component of cost per bed-day; or unit costs net of particular components such as drugs.In addition to reporting estimates for selected countries, the paper shows that unit costs of hospitals vary within countries, sometimes by an order of magnitude. Basing cost-effectiveness studies or budgeting exercises on the results of a study of a single facility, or even a small group of facilities, is likely to be misleading.

Prevalence and risk factors of intestinal parasitism among two indigenous sub-ethnic groups in Peninsular Malaysia.

PubMed

Chin, Yuee Teng; Lim, Yvonne Ai Lian; Chong, Chun Wie; Teh, Cindy Shuan Ju; Yap, Ivan Kok Seng; Lee, Soo Ching; Tee, Mian Zi; Siow, Vinnie Wei Yin; Chua, Kek Heng

2016-07-18

Intestinal parasitic infections (IPIs) among indigenous people have been widely documented in Malaysia, however, the prevalence of these infections remains high. In the past, most studies have focused on specific species of parasites but polyparasitism has received limited attention. In addition, epidemiology studies on indigenous people tend to consider them as a homogenous group, whereas in reality different sub-ethnic groups have different cultural and living practices. Variations in living habits such as personal hygiene practices may predispose different groups to different parasitic infections. To better understand prevalence and risk factors of intestinal parasitism among different sub-ethnic groups, the present study was conducted among two sub-ethnic groups of indigenous people (Temuan and Mah Meri) residing in Selangor state, Malaysia. A cross-sectional study that focused on two distinct sub-ethnic groups was carried out from February to September 2014. Faecal samples were collected from 186 participants and examined using the formalin-ether sedimentation technique. A molecular approach was adopted to conduct a genetic characterisation of the parasites. Additionally, questionnaires were administered to obtain information on the demographics, socio-economic backgrounds and behavioural risks relating to the participants, as well as information about their environments. Statistical analyses (i.e. binary and multivariate logistic regression analyses) were performed to measure risk factors. For Temuan communities, trichuriasis (64.2 %) was the most common infection found, preceding hookworm infection (34 %), ascariasis (7.5 %), giardiasis (14.2 %) and amoebiasis (7.5 %). As for the Mah Meri communities, trichuriasis (77.5 %) prevailed over ascariasis (21.3 %), hookworm (15 %), giardiasis (7.5 %) and amoebiasis (3.8 %). Significant differences in proportions of trichuriasis, ascariasis and hookworm infections were observed between the Temuan and Mah

Depressive symptoms among Mexican medical students: high prevalence and the effect of a group psychoeducation intervention.

PubMed

Melo-Carrillo, Agustin; Van Oudenhove, Lukas; Lopez-Avila, Alberto

2012-02-01

Several studies have demonstrated a higher prevalence of depression among medical students as compared to the general population. On the other hand, psychoeducational interventions have proven its efficacy on diminishing depressive symptoms. The aim of this study is to determine the prevalence of depressive symptoms among medical students in La Salle University and the effect that psychoeducation has on it. Students between the first and the eighth semester voluntarily answered the Beck Depression Inventory test in an anonymous way from 2006 to 2007. After determining the prevalence of depressive symptoms the psychoeducational program was established and prevalence of depressive symptoms was measured for two more years (2008-2009). A total of 1958 students answered the test during the four years. In the first two years (2006-2007) the 36.29% of the students scored for positive depressive symptoms. The next two years (2008-2009), after the psychoeducation program, the prevalence of depressive symptoms diminishes in a significant manner, only 25.51% of the students have depressive symptoms (p<.0001). Because the test were answered anonymously, there is no way we can give neither specific attention nor follow-up to the students with depression. Also we can't determine the effect of the mental health group treatment among the medical students. Even though the medical students have risks factors for developing depression, we prove that a psychoeducation program can be an effective alternative therapy for decreasing the prevalence of depressive symptoms among medical students. Copyright © 2011 Elsevier B.V. All rights reserved.

The Game of Contacts: Estimating the Social Visibility of Groups.

PubMed

Salganik, Matthew J; Mello, Maeve B; Abdo, Alexandre H; Bertoni, Neilane; Fazito, Dimitri; Bastos, Francisco I

2011-01-01

Estimating the sizes of hard-to-count populations is a challenging and important problem that occurs frequently in social science, public health, and public policy. This problem is particularly pressing in HIV/AIDS research because estimates of the sizes of the most at-risk populations-illicit drug users, men who have sex with men, and sex workers-are needed for designing, evaluating, and funding programs to curb the spread of the disease. A promising new approach in this area is the network scale-up method, which uses information about the personal networks of respondents to make population size estimates. However, if the target population has low social visibility, as is likely to be the case in HIV/AIDS research, scale-up estimates will be too low. In this paper we develop a game-like activity that we call the game of contacts in order to estimate the social visibility of groups, and report results from a study of heavy drug users in Curitiba, Brazil (n = 294). The game produced estimates of social visibility that were consistent with qualitative expectations but of surprising magnitude. Further, a number of checks suggest that the data are high-quality. While motivated by the specific problem of population size estimation, our method could be used by researchers more broadly and adds to long-standing efforts to combine the richness of social network analysis with the power and scale of sample surveys.

The prevalence of refractive errors among adults in the United States, Western Europe, and Australia.

PubMed

Kempen, John H; Mitchell, Paul; Lee, Kristine E; Tielsch, James M; Broman, Aimee T; Taylor, Hugh R; Ikram, M Kamran; Congdon, Nathan G; O'Colmain, Benita J

2004-04-01

To estimate the prevalence of refractive errors in persons 40 years and older. Counts of persons with phakic eyes with and without spherical equivalent refractive error in the worse eye of +3 diopters (D) or greater, -1 D or less, and -5 D or less were obtained from population-based eye surveys in strata of gender, race/ethnicity, and 5-year age intervals. Pooled age-, gender-, and race/ethnicity-specific rates for each refractive error were applied to the corresponding stratum-specific US, Western European, and Australian populations (years 2000 and projected 2020). Six studies provided data from 29 281 persons. In the US, Western European, and Australian year 2000 populations 40 years or older, the estimated crude prevalence for hyperopia of +3 D or greater was 9.9%, 11.6%, and 5.8%, respectively (11.8 million, 21.6 million, and 0.47 million persons). For myopia of -1 D or less, the estimated crude prevalence was 25.4%, 26.6%, and 16.4% (30.4 million, 49.6 million, and 1.3 million persons), respectively, of whom 4.5%, 4.6%, and 2.8% (5.3 million, 8.5 million, and 0.23 million persons), respectively, had myopia of -5 D or less. Projected prevalence rates in 2020 were similar. Refractive errors affect approximately one third of persons 40 years or older in the United States and Western Europe, and one fifth of Australians in this age group.

The prevalence and incidence of active syphilis in women in Morocco, 1995-2016: Model-based estimation and implications for STI surveillance

PubMed Central

Bennani, Aziza; El-Kettani, Amina; Hançali, Amina; El-Rhilani, Houssine; Alami, Kamal; Youbi, Mohamed; Rowley, Jane; Abu-Raddad, Laith; Smolak, Alex; Taylor, Melanie; Mahiané, Guy; Stover, John

2017-01-01

Background Evolving health priorities and resource constraints mean that countries require data on trends in sexually transmitted infections (STI) burden, to inform program planning and resource allocation. We applied the Spectrum STI estimation tool to estimate the prevalence and incidence of active syphilis in adult women in Morocco over 1995 to 2016. The results from the analysis are being used to inform Morocco’s national HIV/STI strategy, target setting and program evaluation. Methods Syphilis prevalence levels and trends were fitted through logistic regression to data from surveys in antenatal clinics, women attending family planning clinics and other general adult populations, as available post-1995. Prevalence data were adjusted for diagnostic test performance, and for the contribution of higher-risk populations not sampled in surveys. Incidence was inferred from prevalence by adjusting for the average duration of infection with active syphilis. Results In 2016, active syphilis prevalence was estimated to be 0.56% in women 15 to 49 years of age (95% confidence interval, CI: 0.3%-1.0%), and around 21,675 (10,612–37,198) new syphilis infections have occurred. The analysis shows a steady decline in prevalence from 1995, when the prevalence was estimated to be 1.8% (1.0–3.5%). The decline was consistent with decreasing prevalences observed in TB patients, fishermen and prisoners followed over 2000–2012 through sentinel surveillance, and with a decline since 2003 in national HIV incidence estimated earlier through independent modelling. Conclusions Periodic population-based surveys allowed Morocco to estimate syphilis prevalence and incidence trends. This first-ever undertaking engaged and focused national stakeholders, and confirmed the still considerable syphilis burden. The latest survey was done in 2012 and so the trends are relatively uncertain after 2012. From 2017 Morocco plans to implement a system to record data from routine antenatal

Sex differences in the association between countries' smoking prevalence and happiness ratings.

PubMed

Drehmer, J E

2018-05-02

To examine the cross-sectional relationship between measures of countries' happiness and countries' prevalence of tobacco smoking. Since smoking prevalence differs widely based on sex in some countries and is similar in other countries, it was examined if there was a sex difference in the relationship between smoking prevalence and country-specific happiness ratings. Ecological study design. Countries' age-standardized prevalence estimates of smoking any tobacco product among persons aged 15 years and older (%) for 2015 were obtained from the World Health Organization (WHO) Global Health Observatory. Country-specific scores from the World Happiness Report 2016 Update Ranking of Happiness (2013-15) and the 2015 Gallup Positive Experience Index were matched and correlated to 2015 WHO estimates of tobacco smoking prevalence for males and females. The difference between male and female age-standardized smoking prevalence estimates in each country was calculated by subtracting female prevalence from male prevalence and was then correlated to countries' World Happiness Report scores. The analyses did not control for potential confounders. The association between male age-standardized smoking prevalence estimates and countries' World Happiness Report scores was inversely correlated [r(104) = -0.22, P = 0.03], whereas the association between female age-standardized smoking prevalence estimates and countries' World Happiness Report scores was positively correlated [r(104) = 0.48, P = 0.00]. An inverse correlation was found between the difference in male and female smoking prevalence estimates and countries' World Happiness Report scores [r(104) = -0.50, P = 0.00]. The association between countries' male age-standardized smoking prevalence estimates and the Positive Experience Index scores was inversely correlated [r(99) = -0.37, P = 0.00], whereas the female age-standardized smoking prevalence estimates in countries were not significantly associated with

Bayesian estimation of diagnostic sensitivity and specificity of a nervous necrosis virus antibody ELISA.

PubMed

Jaramillo, Diana; Dürr, Salome; Hick, Paul; Whittington, Richard

2016-01-01

Diagnosis of nervous necrosis virus (NNV) infection in susceptible fish species is mostly performed post-mortem due to the neurotropism of the causative agent and the only validated diagnostic assays require samples from brain and retinal tissue. However, a non-lethal alternative to test for exposure of fish to NNV is needed. An indirect ELISA for the detection of anti-NNV antibodies in was recently developed and evaluated to detect responses in the sera from immunized fish. For this study, we assessed the accuracy of the assay at detecting specific antibodies from naturally exposed fish using field samples from populations with differing infection status. We applied a Bayesian model, using RTqPCR as a second test. Median estimates of the diagnostic sensitivity and specificity of the VNN ELISA were 81.8% and 86.7%, respectively. We concluded that the assay was fit for the purpose of identifying animals in naturally exposed populations. With further evaluation in larger populations the test might be used to inform implementation of control measures, and for estimating infection prevalence to facilitate risk analysis. To our knowledge this is the first report on the diagnostic accuracy of an antibody ELISA for an infectious disease in finfish. Copyright © 2015 Elsevier B.V. All rights reserved.

A Group Contribution Method for Estimating Cetane and Octane Numbers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kubic, William Louis

Much of the research on advanced biofuels is devoted to the study of novel chemical pathways for converting nonfood biomass into liquid fuels that can be blended with existing transportation fuels. Many compounds under consideration are not found in the existing fuel supplies. Often, the physical properties needed to assess the viability of a potential biofuel are not available. The only reliable information available may be the molecular structure. Group contribution methods for estimating physical properties from molecular structure have been used for more than 60 years. The most common application is estimation of thermodynamic properties. More recently, group contributionmore » methods have been developed for estimating rate dependent properties including cetane and octane numbers. Often, published group contribution methods are limited in terms of types of function groups and range of applicability. In this study, a new, broadly-applicable group contribution method based on an artificial neural network was developed to estimate cetane number research octane number, and motor octane numbers of hydrocarbons and oxygenated hydrocarbons. The new method is more accurate over a greater range molecular weights and structural complexity than existing group contribution methods for estimating cetane and octane numbers.« less

Estimating correlation of prevalence at two locations in the farm-to-table continuum using qualitative test data.

PubMed

Williams, Michael S; Ebel, Eric D

2017-03-20

The presence or absence of contaminants in food samples changes as a commodity moves along the farm-to-table continuum. Interest lies in the degree to which the prevalence (i.e., infected animals or contaminated sample units) at one location in the continuum, as measured by the proportion of test-positive samples, is correlated with the prevalence at a location later in the continuum. If prevalence of a contaminant at one location in the continuum is strongly correlated with the prevalence of the contaminant later in the continuum, then the effect of changes in contamination on overall food safety can be better understood. Pearson's correlation coefficient is one of the simplest metrics of association between two measurements of prevalence but it is biased when data consisting of presence/absence testing results are used to directly estimate the correlation. This study demonstrates the potential magnitude of this bias and explores the utility of three methods for unbiased estimation of the degree of correlation in prevalence. An example, based on testing broiler chicken carcasses for Salmonella at re-hang and post-chill, is used to demonstrate the methods. Published by Elsevier B.V.

Sex-Specific Differences in Hemodialysis Prevalence and Practices and the Male-to-Female Mortality Rate: The Dialysis Outcomes and Practice Patterns Study (DOPPS)

PubMed Central

Hecking, Manfred; Bieber, Brian A.; Ethier, Jean; Kautzky-Willer, Alexandra; Sunder-Plassmann, Gere; Säemann, Marcus D.; Ramirez, Sylvia P. B.; Gillespie, Brenda W.; Pisoni, Ronald L.; Robinson, Bruce M.; Port, Friedrich K.

2014-01-01

Background A comprehensive analysis of sex-specific differences in the characteristics, treatment, and outcomes of individuals with end-stage renal disease undergoing dialysis might reveal treatment inequalities and targets to improve sex-specific patient care. Here we describe hemodialysis prevalence and patient characteristics by sex, compare the adult male-to-female mortality rate with data from the general population, and evaluate sex interactions with mortality. Methods and Findings We assessed the Human Mortality Database and 206,374 patients receiving hemodialysis from 12 countries (Australia, Belgium, Canada, France, Germany, Italy, Japan, New Zealand, Spain, Sweden, the UK, and the US) participating in the international, prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) between June 1996 and March 2012. Among 35,964 sampled DOPPS patients with full data collection, we studied patient characteristics (descriptively) and mortality (via Cox regression) by sex. In all age groups, more men than women were on hemodialysis (59% versus 41% overall), with large differences observed between countries. The average estimated glomerular filtration rate at hemodialysis initiation was higher in men than women. The male-to-female mortality rate ratio in the general population varied from 1.5 to 2.6 for age groups <75 y, but in hemodialysis patients was close to one. Compared to women, men were younger (mean = 61.9±standard deviation 14.6 versus 63.1±14.5 y), were less frequently obese, were more frequently married and recipients of a kidney transplant, more frequently had coronary artery disease, and were less frequently depressed. Interaction analyses showed that the mortality risk associated with several comorbidities and hemodialysis catheter use was lower for men (hazard ratio [HR] = 1.11) than women (HR = 1.33, interaction p<0.001). This study is limited by its inability to establish causality for the observed sex-specific differences

High Prevalence of Obesity in Ambulatory Children and Adolescents with Intellectual Disability

ERIC Educational Resources Information Center

Stewart, L.; Van de Ven, L.; Katsarou, V.; Rentziou, E.; Doran, M.; Jackson, P.; Reilly, J. J.; Wilson, D.

2009-01-01

Background: Obesity prevalence is unusually high among adults with intellectual disability (ID). There is limited and conflicting evidence on obesity prevalence among ambulatory children and adolescents with ID. The present study aimed to estimate obesity prevalence in this group and to compare with population prevalence. Methods: Survey of nine…

Geographic variation in the age- and gender-specific prevalence and incidence of epilepsy: analysis of Taiwanese National Health Insurance-based data.

PubMed

Chen, Chih-Chuan; Chen, Li-Sheng; Yen, Ming-Fang; Chen, Hsiu-Hsi; Liou, Horng-Huei

2012-02-01

We studied geographic variation in age- and gender-specific prevalence and incidence of epilepsy in four different areas of Taiwan. By using large-scale, National Health Insurance (NHI)-based data from 2000-2003 in Taiwan, we identified 131,287 patients diagnosed with epilepsy (ICD code 345) receiving at least of one of 11 antiepileptic drugs (AEDs). Information on age, gender, and location were also collected. The multivariable Poisson regression analysis was used to assess the heterogeneity of the morbidity of epilepsy in different regions. External data validation was also performed to assess the accuracy of capturing epilepsy cases through our NHI data set. The age-adjusted prevalence and incidence of epilepsy were 5.85 (per 1,000) between 2000 and 2003 and 97 (per 100,000 person-years) during the follow-up time from 2001 to 2003 in Taiwan. The sensitivity and specificity of ICD-9 coding for epilepsy in the NHI data set were 83.91% and 99.83%, respectively, resulting in a slight overestimation. Male patients had a higher probability of having epilepsy than did females. East Taiwan had significantly higher prevalence and incidence than did other areas. The age-specific incidence pattern in east Taiwan was atypical in that it revealed clustering in young and middle-aged groups. Our study demonstrated geographic variation in epidemiologic patterns of epilepsy within Taiwan. The findings are informative and provide insight into the clinical management of epilepsy based on consideration of different target groups in different areas. Wiley Periodicals, Inc. © 2011 International League Against Epilepsy.

Alignment-free genome tree inference by learning group-specific distance metrics.

PubMed

Patil, Kaustubh R; McHardy, Alice C

2013-01-01

Understanding the evolutionary relationships between organisms is vital for their in-depth study. Gene-based methods are often used to infer such relationships, which are not without drawbacks. One can now attempt to use genome-scale information, because of the ever increasing number of genomes available. This opportunity also presents a challenge in terms of computational efficiency. Two fundamentally different methods are often employed for sequence comparisons, namely alignment-based and alignment-free methods. Alignment-free methods rely on the genome signature concept and provide a computationally efficient way that is also applicable to nonhomologous sequences. The genome signature contains evolutionary signal as it is more similar for closely related organisms than for distantly related ones. We used genome-scale sequence information to infer taxonomic distances between organisms without additional information such as gene annotations. We propose a method to improve genome tree inference by learning specific distance metrics over the genome signature for groups of organisms with similar phylogenetic, genomic, or ecological properties. Specifically, our method learns a Mahalanobis metric for a set of genomes and a reference taxonomy to guide the learning process. By applying this method to more than a thousand prokaryotic genomes, we showed that, indeed, better distance metrics could be learned for most of the 18 groups of organisms tested here. Once a group-specific metric is available, it can be used to estimate the taxonomic distances for other sequenced organisms from the group. This study also presents a large scale comparison between 10 methods--9 alignment-free and 1 alignment-based.

Prevalence estimation and familial tendency of common forefoot deformities in Turkey: A survey of 2662 adults.

PubMed

Şaylı, Uğur; Altunok, Elif Çiğdem; Güven, Melih; Akman, Budak; Biros, Jnev; Şaylı, Ayşe

2018-02-19

This survey was designed to evaluate the prevalence estimations of HV, bunionette, hammertoe as well as their relations to shoe wearing and also familial tendency, in Turkey. Two thousand six hundred sixty two volunteers (1615 females and 1047 males) with a mean age of 34.15 ± 14.23 (range; 18 to 96) years were asked to answer the predetermined questionnaire between January and June, 2016. Hallux valgus, hammertoe and bunionette images were provided as references and every adult participant without any known forefoot problems or past forefoot surgery history was asked to rate his/her foot and to respond the questions about family history and shoe wearing habits. Responses were statistically analyzed. The prevalence estimations of hallux valgus, bunionette and hammertoe were calculated as 54.3%, 13.8% and 8.9% and positive family history rates were 53.2%, 61.2% and 56.1%, respectively. All three deformities were more common in females than in males (p < 0.001). Nonetheless the older age group reported significantly higher prevalence rates for only HV (p < 0.001). Likewise, among the three deformities, females reported a higher rate of positive family history only in HV compared to men (p < 0.001). Constricting shoe wear was found to affect HV incidence in women (p < 0.001) and bunionette incidence in both sexes (p < 0.01). This study concludes that forefoot deformities are common with high familial tendency. Hence it is worthwhile to work on molecular genetics and this may enable the anticipation of forthcoming deformities in order to take early action in prevention, in nearly the half of the population. Copyright © 2018 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

The Spatial Distribution of Adult Obesity Prevalence in Denver County, Colorado: An Empirical Bayes Approach to Adjust EHR-Derived Small Area Estimates.

PubMed

Tabano, David C; Bol, Kirk; Newcomer, Sophia R; Barrow, Jennifer C; Daley, Matthew F

2017-12-06

Measuring obesity prevalence across geographic areas should account for environmental and socioeconomic factors that contribute to spatial autocorrelation, the dependency of values in estimates across neighboring areas, to mitigate the bias in measures and risk of type I errors in hypothesis testing. Dependency among observations across geographic areas violates statistical independence assumptions and may result in biased estimates. Empirical Bayes (EB) estimators reduce the variability of estimates with spatial autocorrelation, which limits the overall mean square-error and controls for sample bias. Using the Colorado Body Mass Index (BMI) Monitoring System, we modeled the spatial autocorrelation of adult (≥ 18 years old) obesity (BMI ≥ 30 kg m 2 ) measurements using patient-level electronic health record data from encounters between January 1, 2009, and December 31, 2011. Obesity prevalence was estimated among census tracts with >=10 observations in Denver County census tracts during the study period. We calculated the Moran's I statistic to test for spatial autocorrelation across census tracts, and mapped crude and EB obesity prevalence across geographic areas. In Denver County, there were 143 census tracts with 10 or more observations, representing a total of 97,710 adults with a valid BMI. The crude obesity prevalence for adults in Denver County was 29.8 percent (95% CI 28.4-31.1%) and ranged from 12.8 to 45.2 percent across individual census tracts. EB obesity prevalence was 30.2 percent (95% CI 28.9-31.5%) and ranged from 15.3 to 44.3 percent across census tracts. Statistical tests using the Moran's I statistic suggest adult obesity prevalence in Denver County was distributed in a non-random pattern. Clusters of EB obesity estimates were highly significant (alpha=0.05) in neighboring census tracts. Concentrations of obesity estimates were primarily in the west and north in Denver County. Statistical tests reveal adult obesity prevalence exhibit spatial

Prevalence of driving with blood drug concentrations above proposed new legal limits in Norway: estimations based on drug concentrations in oral fluid.

PubMed

Gjerde, Hallvard; Normann, Per T; Christophersen, Asbjørg S; Mørland, Jørg

2011-07-15

To estimate the prevalence of driving with blood drug concentrations above the recently proposed Norwegian legal limits for drugged driving in random traffic. The results from a roadside survey of 10,816 drivers was used as basis for the estimation, and the most prevalent drugs were included. Three approaches were used to estimate the prevalence of drug concentrations above the proposed legal limits in blood based on drug concentrations in oral fluid: comparison with drug concentrations observed in oral fluid and blood in pharmacokinetic studies, estimating the prevalence of drug concentrations in blood by calculating the prevalence of drug concentrations in oral fluid that were larger than the limit in blood multiplied with mean oral fluid/blood ratios, and a mathematical simulation mimicking the relationship between drug concentration distributions in blood and oral fluid for populations of drug users. In total, alcohol or drugs were detected in 5.7% of the samples of oral fluid from drivers in normal traffic; 3.8% (n=410) were positive for the drugs that we included in the assessment. The estimation of drug concentrations in blood suggested that about 1.5% had concentrations above the proposed legal limits in blood for the studied drugs, which is about 40% of those who were positive for the drugs in oral fluid. The estimated prevalence of driving with concentrations of psychoactive drugs in blood above the proposed legal limits was for illegal drugs 0.4% and for medicinal drugs 1.1%. These may be regarded as minimum estimates as some drugs were not included in the assessment. These prevalences are higher than the prevalence of driving with blood alcohol concentrations above the legal limit of 0.2g/kg in Norway. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Estimating aquifer transmissivity from specific capacity using MATLAB.

PubMed

McLin, Stephen G

2005-01-01

Historically, specific capacity information has been used to calculate aquifer transmissivity when pumping test data are unavailable. This paper presents a simple computer program written in the MATLAB programming language that estimates transmissivity from specific capacity data while correcting for aquifer partial penetration and well efficiency. The program graphically plots transmissivity as a function of these factors so that the user can visually estimate their relative importance in a particular application. The program is compatible with any computer operating system running MATLAB, including Windows, Macintosh OS, Linux, and Unix. Two simple examples illustrate program usage.

Prevalence of Smoking and Obesity Among U.S. Cancer Survivors: Estimates From the National Health Interview Survey, 2008-2012.

PubMed

Shoemaker, Meredith L; White, Mary C; Hawkins, Nikki A; Hayes, Nikki S

2016-07-01

To describe smoking and obesity prevalence among male and female cancer survivors in the United States.
. Cross-sectional survey.
. Household interviews.
. 9,753 survey respondents who reported ever having a malignancy, excluding nonmelanoma skin cancers. 
. Data from the National Health Interview Survey (2008-2012) were used to calculate weighted smoking status prevalence estimates. Cross-tabulations of smoking and weight status were produced, along with Wald chi-square tests and linear contrasts.
. Cancer history, smoking status, obesity status, gender, age, and age at diagnosis.
. Seventeen percent of cancer survivors reported current smoking. Female survivors had higher rates of current smoking than males, particularly in the youngest age category. Male survivors who currently smoked had lower obesity prevalence rates than males who previously smoked or never smoked. Among female survivors, 31% were obese and no significant differences were seen in obesity prevalence by smoking status for all ages combined. 
. The findings highlight the variation in smoking status and weight by age and gender. Smoking interventions may need to be targeted to address barriers specific to subgroups of cancer survivors.
. Nurses can be instrumental in ensuring that survivors receive comprehensive approaches to address both weight and tobacco use to avoid trading one risk for another.

Prevalence of treated epilepsy in Korea based on national health insurance data.

PubMed

Lee, Seo-Young; Jung, Ki-Young; Lee, Il Keun; Yi, Sang Do; Cho, Yong Won; Kim, Dong Wook; Hwang, Seung-Sik; Kim, Sejin

2012-03-01

The Korean national health security system covers the entire population and all medical facilities. We aimed to estimate epilepsy prevalence, anticonvulsant utilization pattern and the cost. We identified prevalent epilepsy patients by the prescription of anticonvulsants under the diagnostic codes suggesting seizure or epilepsy from 2007 Korean National Health Insurance databases. The information of demography, residential area, the kind of medical security service reflecting economic status, anticonvulsants, and the costs was extracted. The overall prevalence of treated epilepsy patients was 2.41/1,000, and higher for men than women. The age-specific prevalence was the lowest in those in their thirties and forties. Epilepsy was more prevalent among lower-income individuals receiving medical aid. The regional prevalence was the highest in Jeju Island and lowest in Ulsan city. New anticonvulsants were more frequently used than old anticonvulsants in the younger age group. The total annual cost of epilepsy or seizure reached 0.46% of total medical expenditure and 0.27% of total expenditure on health. This is the first nationwide epidemiological report issued on epilepsy in Korea. Epilepsy prevalence in Korea is comparable to those in developed countries. Economic status and geography affect the prevalence of epilepsy.

Frequency of acromegaly in adults with diabetes or glucose intolerance and estimated prevalence in the general population.

PubMed

Rosario, Pedro Weslley

2011-09-01

The objective of this study was to evaluate the frequency of acromegaly in adults with diabetes mellitus (DM) or glucose intolerance (GI) and to estimate its prevalence in the general population. A total of 2,270 patients with DM or GI and age from 20 to 70 years were studied. Patients with known pituitary disease and pregnant women were excluded. Serum IGF-1 was measured in all subjects and, if elevated, a new measurement was obtained together with the measurement of GH in the oral glucose tolerance test (OGTT). Patients with persistently elevated IGF-1 and inadequate suppression of GH were submitted to magnetic resonance imaging (MRI). Acromegaly was not suspected by the assistant physician in any of the patients. Six patients had persistently elevated IGF-1 and inadequate suppression of GH in the OGTT (without other conditions associated with GH or IGF-1 elevation). Pituitary adenoma was detected by MRI in three patients, and two subjects presented an acromegalic phenotype. Two patients were submitted to transsphenoidal surgery, with immunohistochemistry confirming immunoreactivity for GH. Another patient was treated with octreotide LAR which resulted in the normalization of IGF-1 and GH. Considering a prevalence of DM or GI of 20% in adults and the occurrence of these co-morbidities in 55% of patients with acromegaly, the frequency of 3/2,270 found in this study permits to estimate 480 cases/1,000,000 adults. The present results suggest that the prevalence of acromegaly is underestimated and further studies are needed to evaluate the cost-effectiveness of biochemical screening in certain groups of patients.

Early Childhood Developmental Status in Low- and Middle-Income Countries: National, Regional, and Global Prevalence Estimates Using Predictive Modeling.

PubMed

McCoy, Dana Charles; Peet, Evan D; Ezzati, Majid; Danaei, Goodarz; Black, Maureen M; Sudfeld, Christopher R; Fawzi, Wafaie; Fink, Günther

2016-06-01

The development of cognitive and socioemotional skills early in life influences later health and well-being. Existing estimates of unmet developmental potential in low- and middle-income countries (LMICs) are based on either measures of physical growth or proxy measures such as poverty. In this paper we aim to directly estimate the number of children in LMICs who would be reported by their caregivers to show low cognitive and/or socioemotional development. The present paper uses Early Childhood Development Index (ECDI) data collected between 2005 and 2015 from 99,222 3- and 4-y-old children living in 35 LMICs as part of the Multiple Indicator Cluster Survey (MICS) and Demographic and Health Surveys (DHS) programs. First, we estimate the prevalence of low cognitive and/or socioemotional ECDI scores within our MICS/DHS sample. Next, we test a series of ordinary least squares regression models predicting low ECDI scores across our MICS/DHS sample countries based on country-level data from the Human Development Index (HDI) and the Nutrition Impact Model Study. We use cross-validation to select the model with the best predictive validity. We then apply this model to all LMICs to generate country-level estimates of the prevalence of low ECDI scores globally, as well as confidence intervals around these estimates. In the pooled MICS and DHS sample, 14.6% of children had low ECDI scores in the cognitive domain, 26.2% had low socioemotional scores, and 36.8% performed poorly in either or both domains. Country-level prevalence of low cognitive and/or socioemotional scores on the ECDI was best represented by a model using the HDI as a predictor. Applying this model to all LMICs, we estimate that 80.8 million children ages 3 and 4 y (95% CI 48.1 million, 113.6 million) in LMICs experienced low cognitive and/or socioemotional development in 2010, with the largest number of affected children in sub-Saharan Africa (29.4.1 million; 43.8% of children ages 3 and 4 y), followed by

Comparison of DNA testing strategies in monitoring human papillomavirus infection prevalence through simulation.

PubMed

Lin, Carol Y; Li, Ling

2016-11-07

HPV DNA diagnostic tests for epidemiology monitoring (research purpose) or cervical cancer screening (clinical purpose) have often been considered separately. Women with positive Linear Array (LA) polymerase chain reaction (PCR) research test results typically are neither informed nor referred for colposcopy. Recently, a sequential testing by using Hybrid Capture 2 (HC2) HPV clinical test as a triage before genotype by LA has been adopted for monitoring HPV infections. Also, HC2 has been reported as a more feasible screening approach for cervical cancer in low-resource countries. Thus, knowing the performance of testing strategies incorporating HPV clinical test (i.e., HC2-only or using HC2 as a triage before genotype by LA) compared with LA-only testing in measuring HPV prevalence will be informative for public health practice. We conducted a Monte Carlo simulation study. Data were generated using mathematical algorithms. We designated the reported HPV infection prevalence in the U.S. and Latin America as the "true" underlying type-specific HPV prevalence. Analytical sensitivity of HC2 for detecting 14 high-risk (oncogenic) types was considered to be less than LA. Estimated-to-true prevalence ratios and percentage reductions were calculated. When the "true" HPV prevalence was designated as the reported prevalence in the U.S., with LA genotyping sensitivity and specificity of (0.95, 0.95), estimated-to-true prevalence ratios of 14 high-risk types were 2.132, 1.056, 0.958 for LA-only, HC2-only, and sequential testing, respectively. Estimated-to-true prevalence ratios of two vaccine-associated high-risk types were 2.359 and 1.063 for LA-only and sequential testing, respectively. When designated type-specific prevalence of HPV16 and 18 were reduced by 50 %, using either LA-only or sequential testing, prevalence estimates were reduced by 18 %. Estimated-to-true HPV infection prevalence ratios using LA-only testing strategy are generally higher than using HC2-only or

Impact of Disease Prevalence Adjustment on Hospitalization Rates for Chronic Ambulatory Care-Sensitive Conditions in Germany.

PubMed

Pollmanns, Johannes; Romano, Patrick S; Weyermann, Maria; Geraedts, Max; Drösler, Saskia E

2018-04-01

To explore effects of disease prevalence adjustment on ambulatory care-sensitive hospitalization (ACSH) rates used for quality comparisons. County-level hospital administrative data on adults discharged from German hospitals in 2011 and prevalence estimates based on administrative ambulatory diagnosis data were used. A retrospective cross-sectional study using in- and outpatient secondary data was performed. Hospitalization data for hypertension, diabetes, heart failure, chronic obstructive pulmonary disease, and asthma were obtained from the German Diagnosis Related Groups (DRG) database. Prevalence estimates were obtained from the German Central Research Institute of Ambulatory Health Care. Crude hospitalization rates varied substantially across counties (coefficients of variation [CV] 28-37 percent across conditions); this variation was reduced by prevalence adjustment (CV 21-28 percent). Prevalence explained 40-50 percent of the observed variation (r = 0.65-0.70) in ACSH rates for all conditions except asthma (r = 0.07). Between 30 percent and 38 percent of areas moved into or outside condition-specific control limits with prevalence adjustment. Unadjusted ACSH rates should be used with caution for high-stakes public reporting as differences in prevalence may have a marked impact. Prevalence adjustment should be considered in models analyzing ACSH. © Health Research and Educational Trust.

Occupancy Modeling for Improved Accuracy and Understanding of Pathogen Prevalence and Dynamics

PubMed Central

Colvin, Michael E.; Peterson, James T.; Kent, Michael L.; Schreck, Carl B.

2015-01-01

Most pathogen detection tests are imperfect, with a sensitivity < 100%, thereby resulting in the potential for a false negative, where a pathogen is present but not detected. False negatives in a sample inflate the number of non-detections, negatively biasing estimates of pathogen prevalence. Histological examination of tissues as a diagnostic test can be advantageous as multiple pathogens can be examined and providing important information on associated pathological changes to the host. However, it is usually less sensitive than molecular or microbiological tests for specific pathogens. Our study objectives were to 1) develop a hierarchical occupancy model to examine pathogen prevalence in spring Chinook salmon Oncorhynchus tshawytscha and their distribution among host tissues 2) use the model to estimate pathogen-specific test sensitivities and infection rates, and 3) illustrate the effect of using replicate within host sampling on sample sizes required to detect a pathogen. We examined histological sections of replicate tissue samples from spring Chinook salmon O. tshawytscha collected after spawning for common pathogens seen in this population: Apophallus/echinostome metacercariae, Parvicapsula minibicornis, Nanophyetus salmincola/ metacercariae, and Renibacterium salmoninarum. A hierarchical occupancy model was developed to estimate pathogen and tissue-specific test sensitivities and unbiased estimation of host- and organ-level infection rates. Model estimated sensitivities and host- and organ-level infections rates varied among pathogens and model estimated infection rate was higher than prevalence unadjusted for test sensitivity, confirming that prevalence unadjusted for test sensitivity was negatively biased. The modeling approach provided an analytical approach for using hierarchically structured pathogen detection data from lower sensitivity diagnostic tests, such as histology, to obtain unbiased pathogen prevalence estimates with associated uncertainties

Occupancy modeling for improved accuracy and understanding of pathogen prevalence and dynamics

USGS Publications Warehouse

Colvin, Michael E.; Peterson, James T.; Kent, Michael L.; Schreck, Carl B.

2015-01-01

Most pathogen detection tests are imperfect, with a sensitivity < 100%, thereby resulting in the potential for a false negative, where a pathogen is present but not detected. False negatives in a sample inflate the number of non-detections, negatively biasing estimates of pathogen prevalence. Histological examination of tissues as a diagnostic test can be advantageous as multiple pathogens can be examined and providing important information on associated pathological changes to the host. However, it is usually less sensitive than molecular or microbiological tests for specific pathogens. Our study objectives were to 1) develop a hierarchical occupancy model to examine pathogen prevalence in spring Chinook salmonOncorhynchus tshawytscha and their distribution among host tissues 2) use the model to estimate pathogen-specific test sensitivities and infection rates, and 3) illustrate the effect of using replicate within host sampling on sample sizes required to detect a pathogen. We examined histological sections of replicate tissue samples from spring Chinook salmon O. tshawytscha collected after spawning for common pathogens seen in this population:Apophallus/echinostome metacercariae, Parvicapsula minibicornis, Nanophyetus salmincola/metacercariae, and Renibacterium salmoninarum. A hierarchical occupancy model was developed to estimate pathogen and tissue-specific test sensitivities and unbiased estimation of host- and organ-level infection rates. Model estimated sensitivities and host- and organ-level infections rates varied among pathogens and model estimated infection rate was higher than prevalence unadjusted for test sensitivity, confirming that prevalence unadjusted for test sensitivity was negatively biased. The modeling approach provided an analytical approach for using hierarchically structured pathogen detection data from lower sensitivity diagnostic tests, such as histology, to obtain unbiased pathogen prevalence estimates with associated

Epidemiology of Inherited Epidermolysis Bullosa Based on Incidence and Prevalence Estimates From the National Epidermolysis Bullosa Registry.

PubMed

Fine, Jo-David

2016-11-01

Accurate estimation of the incidence and prevalence of each subtype of epidermolysis bullosa (EB) is essential before clinical trials can be designed and sufficient funding allocated by government agencies and third-party insurers for the care of these individuals. To determine the incidence and prevalence of inherited EB stratified by subtype in the United States during a 16-year period. Prospective cross-sectional and longitudinal study. Data were obtained from 3271 patients consecutively enrolled in the National Epidermolysis Bullosa Registry from January 1, 1986, through December 31, 2002, using a detailed instrument created with the assistance of the National Institutes of Health. Analyses were performed in January 1999 and April 2015. Participants were patients of all ages with EB. Extensive clinical and laboratory data were collected on patients who were subclassified and serially revalidated based on published diagnostic recommendations by an international panel of experts. Pertinent to this report, estimates were made of the incidence and prevalence during 2 time frames. During the first 5 years of funding of the registry, the overall incidence and prevalence of inherited EB were 19.60 and 8.22 per 1 million live births, respectively. When reassessed over the entire 16 years of the study, the prevalence rose to 11.07, whereas the overall incidence remained unchanged at 19.57 cases. Changes were also observed within some disease subsets as increased numbers of patients were identified, recruited, followed up longitudinally, and resubclassified as needed over time. For example, in 2002, the prevalence of EBS overall and localized EBS had increased considerably by 30.4% and 25.5%, respectively, whereas the prevalence of generalized intermediate EBS declined by 76.7% as a result of later subclassification of some of those patients into other subtypes. In contrast, no significant change was noted in the overall prevalence of JEB or generalized severe JEB

Review: Prevalence and co-occurrence of addictions in US ethnic/racial groups: Implications for genetic research.

PubMed

Luczak, Susan E; Khoddam, Rubin; Yu, Sheila; Wall, Tamara L; Schwartz, Anna; Sussman, Steve

2017-08-01

We conducted a review of the prevalence and co-occurrence of 12 types of addictions in US ethnic/racial groups and discuss the implications of the results for genetic research on addictions. We utilized MEDLINE and PsycINFO databases to review the literature on alcohol, tobacco, marijuana, illicit drugs, gambling, eating/food, internet, sex, love, exercise, work, and shopping. We present results for each addiction based on total US prevalence, prevalence within ethnic groups, and co-occurrence of addictions among ethnic groups when available. This review indicates very little research has examined the interrelationships of addictive behaviors among US ethnic groups. The studies that exist have focused nearly exclusively on comorbidity of substances and gambling behaviors. Overall findings suggest differences among US ethnic groups in prevalence of addictions and in prevalence of addiction among those who use substances or engage in gambling. Almost no ethnic group comparisons of other addictive behaviors including eating/food, internet, love, sex, exercise, work, and shopping were identified in the literature. Despite large-scale research efforts to examine alcohol and substance use disorders in the United States, few studies have been published that examine these addictive behaviors among ethnic groups, and even fewer examine co-occurrence and comorbidity with other addictions. Even with the limited studies, these findings have implications for genetic research on addictive behaviors. We include a discussion of these implications, including issues of population stratification, disaggregation, admixture, and the interplay between genetic and environmental factors in understanding the etiology and treatment of addictions. (Am J Addict 2017;26:424-436). © 2016 American Academy of Addiction Psychiatry.

Changes in smoking prevalence in Ukraine in 2001–5

PubMed Central

Andreeva, Tatiana I; Krasovsky, Konstantin S

2007-01-01

Objectives To analyse trends in smoking prevalence in Ukraine from three surveys conducted in 2001–5, and to explore correlates of observed changes, in order to estimate the stage of tobacco epidemic in Ukraine. Design Repeated national interview surveys in Ukraine in 2001, 2002 and 2005. Main outcome measure Prevalence of current smoking among the population aged ⩾15 years. Results The age‐standardised prevalence of current smoking in Ukrainian men was 54.8% in 2001 and 66.8% in 2005. Among Ukrainian women, prevalence increased from 11.5% in 2001 to 20.0% in 2005. ORs for yearly increase in prevalence were estimated as 1.164 (95% CI 1.111 to 1.220) for men and 1.187 (1.124 to 1.253) for women, which implies that, on average, 3–4% of men and 1.5–2% of women living in Ukraine join the smoking population each year. Conclusions In Ukraine, smoking prevalence is increasing in most population groups. Among men, the medium deprivation group with secondary education has the highest smoking prevalence. Among women, while the most educated, young and those living in larger cities are the leading group for tobacco use, other groups are also increasing their tobacco use. Tobacco promotion efforts appear to have been significantly more effective in Ukraine than smoking control efforts. The decrease in real cigarette prices in Ukraine in 2001–5 could be the main factor explaining the recent growth in smoking prevalence. PMID:17565141

Prevalence and pattern of epilepsy treatment in different socioeconomic classes in Brazil.

PubMed

Noronha, Ana L A; Borges, Moacir A; Marques, Lucia H N; Zanetta, Dirce M T; Fernandes, Paula T; de Boer, Hanneke; Espíndola, Javier; Miranda, Claudio T; Prilipko, Leonid; Bell, Gail S; Sander, Josemir W; Li, Li M

2007-05-01

The worldwide prevalence of epilepsy is variable, estimated at 10//1,000 people, and access to treatment is also variable. Many people go untreated, particularly in resource-poor countries. To estimate the prevalence of epilepsy and the proportion of people not receiving adequate treatment in different socioeconomic classes in Brazil, a resource-poor country. A door-to-door survey was conducted to assess the prevalence and treatment gap of epilepsy in three areas of two towns in Southeast Brazil with a total population of 96,300 people. A validated screening questionnaire for epilepsy (sensitivity 95.8%, specificity 97.8%) was used. A neurologist further ascertained positive cases. A validated instrument for socioeconomic classification was used. Lifetime prevalence was 9.2/1,000 people [95% CI 8.4-10.0] and the prevalence of active epilepsy was 5.4/1,000 people. This was higher in the more deprived social classes (7.5/1,000 compared with 1.6/1,000 in the less deprived). Prevalence was also higher in elderly people (8.5/1,000). Thirty-eight percent of patients with active epilepsy had inadequate treatment (19% on no medication); the figures were similar in the different socioeconomic groups. The prevalence of epilepsy in Brazil is similar to other resource-poor countries, and the treatment gap is high. Epilepsy is more prevalent among less wealthy people and in elderly people. There is an urgent need for education in Brazil to inform people that epilepsy is a treatable, as well as preventable, condition.

Estimation of prevalence of sarcopenia by using a new bioelectrical impedance analysis in Chinese community-dwelling elderly people.

PubMed

Wang, Hui; Hai, Shan; Cao, Li; Zhou, Jianghua; Liu, Ping; Dong, Bi-Rong

2016-12-28

The aim of the present study was to validate the usefulness of the new octapolar multifrequency bioelectrical impedance analysis (BIA) for assessment of appendicular skeletal muscle mass (ASM) by comparing it with that of dual-energy X-ray absorptiometry (DXA) and to investigate the prevalence of sarcopenia in Chinese community-dwelling elderly according to Asian Working Group for Sarcopenia (AWGS) definition. A cross-sectional study was conducted in communities of Chengdu, China. A total of 944 community-dwelling elderly adults aged ≥60 years were included. ASM was measured by using DXA as a criterion method to validate a standing eight-electrode multifrequency BIA (InBody 720), followed by a further estimation of the prevalence of sarcopenia according the AWGS definition. In the Bland-Altman analysis, no significant difference was found between DXA and BIA based on the ASM measurements. The prevalence of AWGS-defined sarcopenia was 12.5% in the elderly women and 8.2% in the elderly men. BIA is suitable for body composition monitoring (ASM) in elderly Chinese as a fast, noninvasive, and convenient method; therefore, it may be a better choice in large epidemiological studies in the Chinese population. The prevalence of AWGS-defined sarcopenia was approximately 10.4% and increased with age in the Chinese community-dwelling elderly in this study.

Hepatitis C in HIV-infected individuals: a systematic review and meta-analysis of estimated prevalence in Africa.

PubMed

Azevedo, Tiago Castro Lopes; Zwahlen, Marcel; Rauch, Andri; Egger, Matthias; Wandeler, Gilles

2016-01-01

Although hepatitis C virus (HCV) screening is recommended for all HIV-infected patients initiating antiretroviral therapy, data on epidemiologic characteristics of HCV infection in resource-limited settings are scarce. We searched PubMed and EMBASE for studies assessing the prevalence of HCV infection among HIV-infected individuals in Africa and extracted data on laboratory methods used. Prevalence estimates from individual studies were combined for each country using random-effects meta-analysis. The importance of study design, population and setting as well as type of test (anti-HCV antibody tests and polymerase chain reactions) was examined with meta-regression. Three randomized controlled trials, 28 cohort studies and 121 cross-sectional analyses with 108,180 HIV-infected individuals from 35 countries were included. The majority of data came from outpatient populations (55%), followed by blood donors (15%) and pregnant women (14%). Based on estimates from 159 study populations, anti-HCV positivity prevalence ranged between 3.3% (95% confidence interval (CI) 1.8-4.7) in Southern Africa and 42.3% (95% CI 4.1-80.5) in North Africa. Study design, type of setting and age distribution did not influence this prevalence significantly. The prevalence of replicating HCV infection, estimated from data of 29 cohorts, was 2.0% (95% CI 1.5-2.6). Ten studies from nine countries reported the HCV genotype of 74 samples, 53% were genotype 1, 24% genotype 2, 14% genotype 4 and 9% genotypes 3, 5 or 6. The prevalence of anti-HCV antibodies is high in HIV-infected patients in Africa, but replicating HCV infection is rare and varies widely across countries.

Sparse EEG/MEG source estimation via a group lasso

PubMed Central

Lim, Michael; Ales, Justin M.; Cottereau, Benoit R.; Hastie, Trevor

2017-01-01

Non-invasive recordings of human brain activity through electroencephalography (EEG) or magnetoencelphalography (MEG) are of value for both basic science and clinical applications in sensory, cognitive, and affective neuroscience. Here we introduce a new approach to estimating the intra-cranial sources of EEG/MEG activity measured from extra-cranial sensors. The approach is based on the group lasso, a sparse-prior inverse that has been adapted to take advantage of functionally-defined regions of interest for the definition of physiologically meaningful groups within a functionally-based common space. Detailed simulations using realistic source-geometries and data from a human Visual Evoked Potential experiment demonstrate that the group-lasso method has improved performance over traditional ℓ2 minimum-norm methods. In addition, we show that pooling source estimates across subjects over functionally defined regions of interest results in improvements in the accuracy of source estimates for both the group-lasso and minimum-norm approaches. PMID:28604790

Estimating disease prevalence from two-phase surveys with non-response at the second phase

PubMed Central

Gao, Sujuan; Hui, Siu L.; Hall, Kathleen S.; Hendrie, Hugh C.

2010-01-01

SUMMARY In this paper we compare several methods for estimating population disease prevalence from data collected by two-phase sampling when there is non-response at the second phase. The traditional weighting type estimator requires the missing completely at random assumption and may yield biased estimates if the assumption does not hold. We review two approaches and propose one new approach to adjust for non-response assuming that the non-response depends on a set of covariates collected at the first phase: an adjusted weighting type estimator using estimated response probability from a response model; a modelling type estimator using predicted disease probability from a disease model; and a regression type estimator combining the adjusted weighting type estimator and the modelling type estimator. These estimators are illustrated using data from an Alzheimer’s disease study in two populations. Simulation results are presented to investigate the performances of the proposed estimators under various situations. PMID:10931514

Estimating sensitivity and specificity for technology assessment based on observer studies.

PubMed

Nishikawa, Robert M; Pesce, Lorenzo L

2013-07-01

The goal of this study was to determine the accuracy and precision of using scores from a receiver operating characteristic rating scale to estimate sensitivity and specificity. We used data collected in a previous study that measured the improvements in radiologists' ability to classify mammographic microcalcification clusters as benign or malignant with and without the use of a computer-aided diagnosis scheme. Sensitivity and specificity were estimated from the rating data from a question that directly asked the radiologists their biopsy recommendations, which was used as the "truth," because it is the actual recall decision, thus it is their subjective truth. By thresholding the rating data, sensitivity and specificity were estimated for different threshold values. Because of interreader and intrareader variability, estimated sensitivity and specificity values for individual readers could be as much as 100% in error when using rating data compared to using the biopsy recommendation data. When pooled together, the estimates using thresholding the rating data were in good agreement with sensitivity and specificity estimated from the recommendation data. However, the statistical power of the rating data estimates was lower. By simply asking the observer his or her explicit recommendation (eg, biopsy or no biopsy), sensitivity and specificity can be measured directly, giving a more accurate description of empirical variability and the power of the study can be maximized. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

Recent Approaches to Estimate Associations Between Source-Specific Air Pollution and Health.

PubMed

Krall, Jenna R; Strickland, Matthew J

2017-03-01

Estimating health effects associated with source-specific exposure is important for better understanding how pollution impacts health and for developing policies to better protect public health. Although epidemiologic studies of sources can be informative, these studies are challenging to conduct because source-specific exposures (e.g., particulate matter from vehicles) often are not directly observed and must be estimated. We reviewed recent studies that estimated associations between pollution sources and health to identify methodological developments designed to address important challenges. Notable advances in epidemiologic studies of sources include approaches for (1) propagating uncertainty in source estimation into health effect estimates, (2) assessing regional and seasonal variability in emissions sources and source-specific health effects, and (3) addressing potential confounding in estimated health effects. Novel methodological approaches to address challenges in studies of pollution sources, particularly evaluation of source-specific health effects, are important for determining how source-specific exposure impacts health.

Estimation of group means when adjusting for covariates in generalized linear models.

PubMed

Qu, Yongming; Luo, Junxiang

2015-01-01

Generalized linear models are commonly used to analyze categorical data such as binary, count, and ordinal outcomes. Adjusting for important prognostic factors or baseline covariates in generalized linear models may improve the estimation efficiency. The model-based mean for a treatment group produced by most software packages estimates the response at the mean covariate, not the mean response for this treatment group for the studied population. Although this is not an issue for linear models, the model-based group mean estimates in generalized linear models could be seriously biased for the true group means. We propose a new method to estimate the group mean consistently with the corresponding variance estimation. Simulation showed the proposed method produces an unbiased estimator for the group means and provided the correct coverage probability. The proposed method was applied to analyze hypoglycemia data from clinical trials in diabetes. Copyright © 2014 John Wiley & Sons, Ltd.

Taxation reduces social disparities in adult smoking prevalence.

PubMed

Siahpush, Mohammad; Wakefield, Melanie A; Spittal, Matt J; Durkin, Sarah J; Scollo, Michelle M

2009-04-01

The CDC, the WHO, and the World Bank promote increases in the price of cigarettes as an effective and important tobacco-control strategy. This study was designed to assess the extent to which the association between the price of cigarettes and smoking prevalence, as measured monthly, varies by income group. Australian population survey data collected monthly from January 1991 to December 2006 were used to estimate Poisson regression models to assess the impact of the price of cigarettes on smoking prevalence across three income groups. Analyses were conducted in 2008. There was strong evidence that real price and prevalence were negatively associated (p<0.001) and that the association was stronger in lower-income groups (p<0.001). One Australian dollar increase in price was associated with a decline of 2.6%, 0.3%, and 0.2% in the prevalence of smoking among low-, medium-, and high-income groups, respectively. Increasing the price of cigarettes not only is an effective tobacco-control strategy to lower smoking prevalence in the general population, but also may provide a means of reducing social disparities in smoking.

The effect of participant nonresponse on HIV prevalence estimates in a population-based survey in two informal settlements in Nairobi city

PubMed Central

2010-01-01

Background Participant nonresponse in an HIV serosurvey can affect estimates of HIV prevalence. Nonresponse can arise from a participant's refusal to provide a blood sample or the failure to trace a sampled individual. In a serosurvey conducted by the African Population and Health Research Center and Kenya Medical Research Centre in the slums of Nairobi, 43% of sampled individuals did not provide a blood sample. This paper describes selective participation in the serosurvey and estimates bias in HIV prevalence figures. Methods The paper uses data derived from an HIV serosurvey nested in an on-going demographic surveillance system. Nonresponse was assessed using logistic regression and multiple imputation methods to impute missing data for HIV status using a set of common variables available for all sampled participants. Results Age, residence, high mobility, wealth, and ethnicity were independent predictors of a sampled individual not being contacted. Individuals aged 30-34 years, females, individuals from the Kikuyu and Kamba ethnicity, married participants, and residents of Viwandani were all less likely to accept HIV testing when contacted. Although men were less likely to be contacted, those found were more willing to be tested compared to females. The overall observed HIV prevalence was overestimated by 2%. The observed prevalence for male participants was underestimated by about 1% and that for females was overestimated by 3%. These differences were small and did not affect the overall estimate substantially as the observed estimates fell within the confidence limits of the corrected prevalence estimate. Conclusions Nonresponse in the HIV serosurvey in the two informal settlements was high, however, the effect on overall prevalence estimate was minimal. PMID:20649957

Early Mathematics Achievement Trajectories: English-Language Learner and Native English-Speaker Estimates, Using the Early Childhood Longitudinal Survey

PubMed Central

Roberts, Greg; Bryant, Diane

2012-01-01

This study used data from the Early Childhood Longitudinal Survey, Kindergarten Class of 1998 –1999, to (a) estimate mathematics achievement trends through 5th grade in the population of students who are English-language proficient by the end of kindergarten, (b) compare trends across primary language groups within this English-language proficient group, (c) evaluate the effect of low socioeconomic status (SES) for English-language proficient students and within different primary language groups, and (d) estimate language-group trends in specific mathematics skill areas. The group of English-language proficient English-language learners (ELLs) was disaggregated into native Spanish speakers and native speakers of Asian languages, the 2 most prevalent groups of ELLs in the United States. Results of multilevel latent variable growth modeling suggest that primary language may be less salient than SES in explaining the mathematics achievement of English-language proficient ELLs. The study also found that mathematics-related school readiness is a key factor in explaining subsequent achievement differences and that the readiness gap is prevalent across the range of mathematics-related skills. PMID:21574702

Can supervised group exercises including ergonomic advice reduce the prevalence and severity of low back pain and pelvic girdle pain in pregnancy? A randomized controlled trial.

PubMed

Eggen, Marit Horst; Stuge, Britt; Mowinckel, Petter; Jensen, Kjersti Smee; Hagen, Kåre Birger

2012-06-01

Many women have low back pain (LBP) or pelvic girdle pain (PGP) during pregnancy, but there is limited evidence of effective primary and secondary preventive strategies. The purpose of this study was to investigate whether a group-based exercise program can reduce the prevalence and severity of LBP and PGP in pregnant women. An observer-blinded randomized controlled trial with equal assignments to a training group and a control group was conducted. The study was conducted in primary care maternity units in 2 suburban municipalities in the southeastern part of Norway. The participants were 257 pregnant women who were healthy and between 18 and 40 years of age before gestation week 20. The training group received supervised exercises in groups once a week, and the control group received standard care. The main outcome measures were self-reported LBP and self-reported PGP. Secondary outcome measures were pain intensity in the morning and evening, disability, and 8-Item Short-Form Health Survey (SF-8) Physical Component Summary (PCS) and Mental Component Summary (MCS) scores. Follow-up measurements were performed at gestation weeks 24, 28, 32, and 36. Overall, there was no effect of the program on the prevalence of PGP (odds ratio = 1.03, 95% confidence interval [CI] = 0.66 to 1.59) or LBP (odds ratio = 0.77, 95% CI = 0.50 to 1.19). For the secondary outcomes, the estimated mean differences between the groups were -0.4 (95% CI = -0.8 to 0.1) for pain intensity in the morning, -0.4 (95% CI = -1.0 to 0.2) for pain intensity in the evening, -1.0 (95% CI = -2.2 to 0.0) for disability, 1.8 (95% CI = 0.0 to 3.7) for the SF-8 PCS, and -0.6 (95% CI = -2.2 to 1.4) for the SF-8 MCS. Due to low statistical power, the estimates for the primary outcomes are imprecise. Supervised group exercise did not reduce the prevalence of LBP or PGP in pregnancy.

Prevalence of older people with intellectual disability in Sweden: a spatial epidemiological analysis.

PubMed

Ng, N; Sandberg, M; Ahlström, G

2015-12-01

The expected increase in longevity of individuals with intellectual disabilities (ID) in many countries of the world is a direct result of medical and social advances, which have also extended the longevity of the general population. It is important to assess the need for social services for people with ID across different administrative levels to ensure sufficient resources are allocated to where they are most needed. This study estimates the annual prevalence of older people with ID from 2004 to 2012 and in different counties and municipalities in Sweden, by sex and age group; identifies proxy indicators related to the care of older people with ID in different counties in 2012 in Sweden and analyses the spatial distribution and clustering of municipalities with a high prevalence of older people with ID. Individuals with ID were identified through the national register based on the Swedish Act concerning Support and Service for Persons with Certain Functional Impairments (the LSS act) and the national death register. This study focuses on older individuals aged 55+ during the period of 2004-2012. The estimated prevalence was calculated at the county and municipality level and plotted on a municipality-level map. Moran's I statistics was used to identify any spatial clustering of municipalities with a large number of individuals with ID. The prevalence of ID among older individuals aged 55+ in Sweden increased from 2004 to 2012. The prevalence was consistently higher among men, and the gender gap increased slightly in recent years. Age-specific prevalence estimates showed ID to be higher in younger age groups, and the gender gap decreased in older age groups. The prevalence was higher in northern counties in Sweden (over 500 individuals per 100 000 population aged 55+). Higher prevalence areas were clustered in northern municipalities, whereas municipalities with high prevalence of older individuals with ID in the middle and southern regions of Sweden demonstrated

Site Specific Probable Maximum Precipitation Estimates and Professional Judgement

NASA Astrophysics Data System (ADS)

Hayes, B. D.; Kao, S. C.; Kanney, J. F.; Quinlan, K. R.; DeNeale, S. T.

2015-12-01

State and federal regulatory authorities currently rely upon the US National Weather Service Hydrometeorological Reports (HMRs) to determine probable maximum precipitation (PMP) estimates (i.e., rainfall depths and durations) for estimating flooding hazards for relatively broad regions in the US. PMP estimates for the contributing watersheds upstream of vulnerable facilities are used to estimate riverine flooding hazards while site-specific estimates for small water sheds are appropriate for individual facilities such as nuclear power plants. The HMRs are often criticized due to their limitations on basin size, questionable applicability in regions affected by orographic effects, their lack of consist methods, and generally by their age. HMR-51 for generalized PMP estimates for the United States east of the 105th meridian, was published in 1978 and is sometimes perceived as overly conservative. The US Nuclear Regulatory Commission (NRC), is currently reviewing several flood hazard evaluation reports that rely on site specific PMP estimates that have been commercially developed. As such, NRC has recently investigated key areas of expert judgement via a generic audit and one in-depth site specific review as they relate to identifying and quantifying actual and potential storm moisture sources, determining storm transposition limits, and adjusting available moisture during storm transposition. Though much of the approach reviewed was considered a logical extension of HMRs, two key points of expert judgement stood out for further in-depth review. The first relates primarily to small storms and the use of a heuristic for storm representative dew point adjustment developed for the Electric Power Research Institute by North American Weather Consultants in 1993 in order to harmonize historic storms for which only 12 hour dew point data was available with more recent storms in a single database. The second issue relates to the use of climatological averages for spatially

Estimates of global and regional prevalence of neural tube defects for 2015: a systematic analysis.

PubMed

Blencowe, Hannah; Kancherla, Vijaya; Moorthie, Sowmiya; Darlison, Matthew W; Modell, Bernadette

2018-02-01

Neural tube defects (NTDs) are associated with substantial mortality, morbidity, disability, and psychological and economic costs. Many are preventable with folic acid, and access to appropriate services for those affected can improve survival and quality of life. We used a compartmental model to estimate global and regional birth prevalence of NTDs (live births, stillbirths, and elective terminations of pregnancy) and subsequent under-5 mortality. Data were identified through web-based reviews of birth defect registry databases and systematic literature reviews. Meta-analyses were undertaken where appropriate. For 2015, our model estimated 260,100 (uncertainty interval (UI): 213,800-322,000) NTD-affected birth outcomes worldwide (prevalence 18.6 (15.3-23.0)/10,000 live births). Approximately 50% of cases were elective terminations of pregnancy for fetal anomalies (UI: 59,300 (47,900-74,500)) or stillbirths (57,800 (UI: 35,000-88,600)). Of NTD-affected live births, 117,900 (∼75%) (UI: 105,500-186,600) resulted in under-5 deaths. Our systematic review showed a paucity of high-quality data in the regions of the world with the highest burden. Despite knowledge about prevention, NTDs remain highly prevalent worldwide. Lack of surveillance and incomplete ascertainment of affected pregnancies make NTDs invisible to policy makers. Improved surveillance of all adverse outcomes is needed to improve the robustness of total NTD prevalence estimation, evaluate effectiveness of prevention through folic acid fortification, and improve outcomes through care and rehabilitation. © 2018 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals Inc. on behalf of New York Academy of Sciences.

Clustering of Helicobacter pylori infection in couples: differences between high- and low-prevalence population groups.

PubMed

Brenner, Hermann; Weyermann, Maria; Rothenbacher, Dietrich

2006-07-01

Several mostly small-scale studies reported clustering of Helicobacter pylori infections as a possible indicator of conjugal transmission, but results have been inconsistent. We assessed clustering of H pylori infections in a large community-based study from Germany that included both high-prevalence and low-prevalence population subgroups. Current H pylori infection was determined among 670 couples by means of carbon-13-urea breath test ((13)C-UBT) breath test and a monoclonal antigen immunoassay for H pylori in stool. Prevalences of infection among women were 34.9% (51 of 146 women) if the partner was infected and 14.5% (76 of 524 women) if the partner was not infected. Stratification by nationality showed a strong association of infection for partners with other than German nationality (adjusted odds ratio [OR], 6.05; 95% confidence interval [CI], 1.31-17.96), for whom prevalence of infection was greater than 50%, whereas no association was seen for German partners born in Germany (OR, 1.10; 95% CI, 0.47-2.61), for whom infection prevalence was approximately 10% (p for interaction = 0.048). Conjugal transmission of infection caused by H pylori is unlikely to be of relevance in low-prevalence population groups. Our results are consistent with the hypothesis of a potential role of conjugal transmission of H pylori infection in high-prevalence population groups.

Estimates of lifetime infertility from three states: the behavioral risk factor surveillance system.

PubMed

Crawford, Sara; Fussman, Chris; Bailey, Marie; Bernson, Dana; Jamieson, Denise J; Murray-Jordan, Melissa; Kissin, Dmitry M

2015-07-01

Knowledge of state-specific infertility is limited. The objectives of this study were to explore state-specific estimates of lifetime prevalence of having ever experienced infertility, sought treatment for infertility, types of treatments sought, and treatment outcomes. Male and female adult residents aged 18-50 years from three states involved in the States Monitoring Assisted Reproductive Technology Collaborative (Florida, Massachusetts, and Michigan) were asked state-added infertility questions as part of the 2012 Behavioral Risk Factor Surveillance System, a state-based, health-related telephone survey. Analysis involved estimation of lifetime prevalence of infertility. The estimated lifetime prevalence of infertility among 1,285 adults in Florida, 1,302 in Massachusetts, and 3,360 in Michigan was 9.7%, 6.0%, and 4.2%, respectively. Among 736 adults in Florida, 1,246 in Massachusetts, and 2,742 in Michigan that have ever tried to get pregnant, the lifetime infertility prevalence was 25.3% in Florida, 9.9% in Massachusetts, and 5.8% in Michigan. Among those with a history of infertility, over half sought treatment (60.7% in Florida, 70.6% in Massachusetts, and 51.6% in Michigan), the most common being non-assisted reproductive technology fertility treatments (61.3% in Florida, 66.0% in Massachusetts, and 75.9% in Michigan). State-specific estimates of lifetime infertility prevalence in Florida, Massachusetts, and Michigan varied. Variations across states are difficult to interpret, as they likely reflect both true differences in prevalence and differences in data collection questionnaires. State-specific estimates are needed for the prevention, detection, and management of infertility, but estimates should be based on a common set of questions appropriate for these goals.

Estimates of Lifetime Infertility from Three States: The Behavioral Risk Factor Surveillance System

PubMed Central

Crawford, Sara; Fussman, Chris; Bailey, Marie; Bernson, Dana; Jamieson, Denise J.; Murray-Jordan, Melissa; Kissin, Dmitry M.

2016-01-01

Background Knowledge of state-specific infertility is limited. The objectives of this study were to explore state-specific estimates of lifetime prevalence of having ever experienced infertility, sought treatment for infertility, types of treatments sought, and treatment outcomes. Methods Male and female adult residents aged 18–50 years from three states involved in the States Monitoring Assisted Reproductive Technology Collaborative (Florida, Massachusetts, and Michigan) were asked state-added infertility questions as part of the 2012 Behavioral Risk Factor Surveillance System, a state-based, health-related telephone survey. Analysis involved estimation of lifetime prevalence of infertility. Results The estimated lifetime prevalence of infertility among 1,285 adults in Florida, 1,302 in Massachusetts, and 3,360 in Michigan was 9.7%, 6.0%, and 4.2%, respectively. Among 736 adults in Florida, 1,246 in Massachusetts, and 2,742 in Michigan that have ever tried to get pregnant, the lifetime infertility prevalence was 25.3% in Florida, 9.9% in Massachusetts, and 5.8% in Michigan. Among those with a history of infertility, over half sought treatment (60.7% in Florida, 70.6% in Massachusetts, and 51.6% in Michigan), the most common being non–assisted reproductive technology fertility treatments (61.3% in Florida, 66.0% in Massachusetts, and 75.9% in Michigan). Conclusion State-specific estimates of lifetime infertility prevalence in Florida, Massachusetts, and Michigan varied. Variations across states are difficult to interpret, as they likely reflect both true differences in prevalence and differences in data collection questionnaires. State-specific estimates are needed for the prevention, detection, and management of infertility, but estimates should be based on a common set of questions appropriate for these goals. PMID:26172998

Utilizing Healthcare Developments, Demographic Data with Statistical Techniques to Estimate the Diarrhoea Prevalence in India.

PubMed

Srivastava, Shweta; Vatsalya, Vatsalya; Arora, Ashoo; Arora, Kashmiri L; Karch, Robert

2012-03-22

Diarrhoea is one of the leading causes of morbidity and mortality in developing countries in Africa and South Asia such as India. Prevalence of diarrheal diseases in those countries is higher than developed western world and largely has been associated with socio-economic and sanitary conditions. However, present available data has not been sufficiently evaluated to study the role of other factors like healthcare development, population density, sex and regional influence on diarrheal prevalence pattern. Study was performed to understand the relationship of diarrheal prevalence with specific measures namely; healthcare services development, demographics, population density, socio-economic conditions, sex, and regional prevalence patterns in India. Data from Annual national health reports and other epidemiological studies were included and statistically analyzed. Our results demonstrate significant correlation of the disease prevalence pattern with certain measures like healthcare centers, population growth rate, sex and region-specific morbidity. Available information on sanitation like water supply and toilet availability and socioeconomic conditions like poverty and literacy measures could only be associated as trends of significance. This study can be valuable for improvisation of appropriate strategies focused on important measures like healthcare resources, population growth and regional significances to evaluate prevalence patterns and management of the diarrhoea locally and globally.

Red cell antigen prevalence predicted by molecular testing in ethnic groups of South Texas blood donors.

PubMed

Aranda, Lorena I; Smith, Linda A; Jones, Scott; Beddard, Rachel

2015-01-01

Alloimmunization to red blood cell antigens is seen in patients receiving chronic blood transfusion. Knowing the prevalence of blood group antigens of the different ethnicities of South Texas donors can provide better management of rare blood inventory for patients in this geographical area. A total of 4369 blood donors were tested and analyzed for various antigens in the following blood group systems: ABO, Rh, Kell, Duffy, Kidd, MNS, Lutheran, Dombrock, Landsteiner-Wiener, Diego, Colton, and Scianna. Donors tested to be group 0 or A were serologically tested for the Rh (C, E, c, e) antigens. Those that tested as presumably R1R1, R2R2, or Ror were then genotyped. Donors constituted three major ethnicities: black (18.3%), Hispanic (36.3%), and Caucasian (41.1%); ethnicities comprised of Asian, American Indian, multiracial, and other accounted for the remaining donors (4.3%). The most likely common Rh phenotype for each ethnicity is as follows: black -Ror (44.4%), Hispanic -R1R1 (59.0%), and Caucasian -R1R1 (38.9%). The prevalence of Kell, Duffy, and Kidd blood group system antigens in black and Caucasian donors is comparable with published reports for the entire U.S. The black South Texas donor population had an 8.8 percent increase in prevalence of the Fy(a+b-) phenotype as compared with these published reports; the Hispanic South Texas donor population had a prevalence of 36.1 percent of the Fy(a+b-) phenotype. Regarding the Diego blood group system, the Hispanic donor population in South Texas had a prevalence of 93.5 percent for the Di(a-b+) phenotype as compared with published reports for the entire U.S. (>99.9%). The Hispanic population had a prevalence of 7.9 percent of donors testing as M-N+S-s+ as compared with 20.2 percent and 15.6 percent for black and Caucasian donors, respectively. This study helped us determine the prevalence of each of the blood group antigens in the South Texas donor population to establish and maintain adequate rare inventory of

Estimation of Listeria monocytogenes and Escherichia coli O157:H7 prevalence and levels in naturally contaminated rocket and cucumber samples by deterministic and stochastic approaches.

PubMed

Hadjilouka, Agni; Mantzourani, Kyriaki-Sofia; Katsarou, Anastasia; Cavaiuolo, Marina; Ferrante, Antonio; Paramithiotis, Spiros; Mataragas, Marios; Drosinos, Eleftherios H

2015-02-01

The aims of the present study were to determine the prevalence and levels of Listeria monocytogenes and Escherichia coli O157:H7 in rocket and cucumber samples by deterministic (estimation of a single value) and stochastic (estimation of a range of values) approaches. In parallel, the chromogenic media commonly used for the recovery of these microorganisms were evaluated and compared, and the efficiency of an enzyme-linked immunosorbent assay (ELISA)-based protocol was validated. L. monocytogenes and E. coli O157:H7 were detected and enumerated using agar Listeria according to Ottaviani and Agosti plus RAPID' L. mono medium and Fluorocult plus sorbitol MacConkey medium with cefixime and tellurite in parallel, respectively. Identity was confirmed with biochemical and molecular tests and the ELISA. Performance indices of the media and the prevalence of both pathogens were estimated using Bayesian inference. In rocket, prevalence of both L. monocytogenes and E. coli O157:H7 was estimated at 7% (7 of 100 samples). In cucumber, prevalence was 6% (6 of 100 samples) and 3% (3 of 100 samples) for L. monocytogenes and E. coli O157:H7, respectively. The levels derived from the presence-absence data using Bayesian modeling were estimated at 0.12 CFU/25 g (0.06 to 0.20) and 0.09 CFU/25 g (0.04 to 0.170) for L. monocytogenes in rocket and cucumber samples, respectively. The corresponding values for E. coli O157:H7 were 0.59 CFU/25 g (0.43 to 0.78) and 1.78 CFU/25 g (1.38 to 2.24), respectively. The sensitivity and specificity of the culture media differed for rocket and cucumber samples. The ELISA technique had a high level of cross-reactivity. Parallel testing with at least two culture media was required to achieve a reliable result for L. monocytogenes or E. coli O157:H7 prevalence in rocket and cucumber samples.

[Ischemic heart disease prevalence estimated using a standard algorithm based on electronic health data in various areas of Italy].

PubMed

Balzi, Daniela; Barchielli, Alessandro; Battistella, Giuseppe; Gnavi, Roberto; Inio, Andrea; Tessari, Roberta; Picariello, Roberta; Canova, Cristina; Simonato, Lorenzo

2008-01-01

to define an algorithm to estimate prevalence of ischemic heart disease from health administrative datasets. four Italian areas: Venezia, Treviso, Torino, Firenze. resident population in the four areas in the period 2002-2004 (only 2003 for Firenze) for a total of 2,350,000 inhabitants in 2003. annual crude and standardized prevalence rate (x100 inhabitants), 95% confidence intervals by area. Quality (comparability and coherence) indicators are also reported the algorithm is based on record linkage of hospital discharges (SDO), pharmacological prescriptions (PF), exemptions from health-tax exemptions (ET) and causes of mortality (CM). From SDO we extracted discharges for ICD9-CM codes 410*-414* in all diagnoses in the estimation year and during the four years immediately preceding. We selected from PF subjects with at least two prescriptions of organic nitrates (ATC = C01DA*) in the estimation year. From ET subjects with a new exemption for ischemic heart disease (002.414) or who obtained exemption in the three years preceding, were selected. We also considered all deaths in the year for ischemic heart disease (ICD9 CM 410-414). Cases were defined as ischemic heart disease prevalent cases if they were extracted at least once from one of the datasets and if they were alive on January 1 of the estimation year. estimated crude prevalence ranges from 2.5 to 4%. The standardized prevalence led to a narrower range of values (2.8-3.3%). Venezia and Firenze show a higher standardized prevalence in both sexes (men 4.7% and 4.4%; women 2.3% and 2.2% respectively); Treviso and Torino present a lower standardized prevalence (men: 3.9%; women: 1.9%). The hospital discharges are the main source to identify prevalent subjects (34-48% of subjects are solely identified by SDO), pharmacological prescriptions are a relevant source in Firenze and Torino (27-28%), while they are less relevant in Venezia and Treviso (13-15%). ET shows a different contribution to prevalent case

Randomized response estimates for the 12-month prevalence of cognitive-enhancing drug use in university students.

PubMed

Dietz, Pavel; Striegel, Heiko; Franke, Andreas G; Lieb, Klaus; Simon, Perikles; Ulrich, Rolf

2013-01-01

To estimate the 12-month prevalence of cognitive-enhancing drug use. Paper-and-pencil questionnaire that used the randomized response technique. University in Mainz, Germany. A total of 2569 university students who completed the questionnaire. An anonymous, specialized questionnaire that used the randomized response technique was distributed to students at the beginning of classes and was collected afterward. From the responses, we calculated the prevalence of students taking drugs only to improve their cognitive performance and not to treat underlying mental disorders such as attention-deficit-hyperactivity disorder, depression, and sleep disorders. The estimated 12-month prevalence of using cognitive-enhancing drugs was 20%. Prevalence varied by sex (male 23.7%, female 17.0%), field of study (highest in students studying sports-related fields, 25.4%), and semester (first semester 24.3%, beyond first semester 16.7%). To our knowledge, this is the first time that the randomized response technique has been used to survey students about cognitive-enhancing drug use. Using the randomized response technique, our questionnaire provided data that showed a high 12-month prevalence of cognitive-enhancing drug use in German university students. Our study suggests that other direct survey techniques have underestimated the use of these drugs. Drug prevention programs need to be established at universities to address this issue. © 2013 Pharmacotherapy Publications, Inc.

Chronic disease prevalence from Italian administrative databases in the VALORE project: a validation through comparison of population estimates with general practice databases and national survey

PubMed Central

2013-01-01

Background Administrative databases are widely available and have been extensively used to provide estimates of chronic disease prevalence for the purpose of surveillance of both geographical and temporal trends. There are, however, other sources of data available, such as medical records from primary care and national surveys. In this paper we compare disease prevalence estimates obtained from these three different data sources. Methods Data from general practitioners (GP) and administrative transactions for health services were collected from five Italian regions (Veneto, Emilia Romagna, Tuscany, Marche and Sicily) belonging to all the three macroareas of the country (North, Center, South). Crude prevalence estimates were calculated by data source and region for diabetes, ischaemic heart disease, heart failure and chronic obstructive pulmonary disease (COPD). For diabetes and COPD, prevalence estimates were also obtained from a national health survey. When necessary, estimates were adjusted for completeness of data ascertainment. Results Crude prevalence estimates of diabetes in administrative databases (range: from 4.8% to 7.1%) were lower than corresponding GP (6.2%-8.5%) and survey-based estimates (5.1%-7.5%). Geographical trends were similar in the three sources and estimates based on treatment were the same, while estimates adjusted for completeness of ascertainment (6.1%-8.8%) were slightly higher. For ischaemic heart disease administrative and GP data sources were fairly consistent, with prevalence ranging from 3.7% to 4.7% and from 3.3% to 4.9%, respectively. In the case of heart failure administrative estimates were consistently higher than GPs’ estimates in all five regions, the highest difference being 1.4% vs 1.1%. For COPD the estimates from administrative data, ranging from 3.1% to 5.2%, fell into the confidence interval of the Survey estimates in four regions, but failed to detect the higher prevalence in the most Southern region (4.0% in

Prevalence of food sensitization and probable food allergy among adults in India: the EuroPrevall INCO study.

PubMed

Mahesh, P A; Wong, Gary W K; Ogorodova, L; Potts, J; Leung, T F; Fedorova, O; Holla, Amrutha D; Fernandez-Rivas, M; Clare Mills, E N; Kummeling, I; Versteeg, S A; van Ree, R; Yazdanbakhsh, M; Burney, P

2016-07-01

Data are lacking regarding the prevalence of food sensitization and probable food allergy among general population in India. We report the prevalence of sensitization and probable food allergy to 24 common foods among adults from general population in Karnataka, South India. The study was conducted in two stages: a screening study and a case-control study. A total of 11 791 adults in age group 20-54 were randomly sampled from general population in South India and answered a screening questionnaire. A total of 588 subjects (236 cases and 352 controls) participated in the case-control study involving a detailed questionnaire and specific IgE estimation for 24 common foods. A high level of sensitization (26.5%) was observed for most of the foods in the general population, higher than that observed among adults in Europe, except for those foods that cross-react with birch pollen. Most of the sensitization was observed in subjects who had total IgE above the median IgE level. A high level of cross-reactivity was observed among different pollens and foods and among foods. The prevalence of probable food allergy (self-reports of adverse symptoms after the consumption of food and specific IgE to the same food) was 1.2%, which was mainly accounted for cow's milk (0.5%) and apple (0.5%). Very high levels of sensitization were observed for most foods, including those not commonly consumed in the general population. For the levels of sensitization, the prevalence of probable food allergy was low. This disassociation needs to be further explored in future studies. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Asian Americans: diabetes prevalence across U.S. and World Health Organization weight classifications.

PubMed

Oza-Frank, Reena; Ali, Mohammed K; Vaccarino, Viola; Narayan, K M Venkat

2009-09-01

To compare diabetes prevalence among Asian Americans by World Health Organization and U.S. BMI classifications. Data on Asian American adults (n = 7,414) from the National Health Interview Survey for 1997-2005 were analyzed. Diabetes prevalence was estimated across weight and ethnic group strata. Regardless of BMI classification, Asian Indians and Filipinos had the highest prevalence of overweight (34-47 and 35-47%, respectively, compared with 20-38% in Chinese; P < 0.05). Asian Indians also had the highest ethnic-specific diabetes prevalence (ranging from 6-7% among the normal weight to 19-33% among the obese) compared with non-Hispanic whites: odds ratio (95% CI) for Asian Indians 2.0 (1.5-2.6), adjusted for age and sex, and 3.1 (2.4-4.0) with additional adjustment for BMI. Asian Indian ethnicity, but not other Asian ethnicities, was strongly associated with diabetes. Weight classification as a marker of diabetes risk may need to accommodate differences across Asian subgroups.

A systematic review of anxiety prevalence in adults within primary care and community settings in Malaysia.

PubMed

Wong, Chin Hoong; Sultan Shah, Zia U Bakt; Teng, Cheong Lieng; Lin, Tzi Quen; Majeed, Zainab Abdul; Chan, Chun Wai

2016-12-01

Anxiety disorders are common mental health disorders with significant impact on the individual as well as burden on the country as a whole. A systematic review of databases, reference lists, internet sources, and input from content experts revealed 42 studies that documented the prevalence of anxiety symptoms or disorders. 12 of these studies specifically evaluated anxiety disorders. 4 studies looked at the prevalence of anxiety disorders in the general population, whilst the remainder focused on selected population groups: university students (4 studies); substance abuse (3 studies); and victims of abuse (1 study). Studies in the general population showed that the prevalence of generalised anxiety disorder was 0.4-5.6%, mixed anxiety and depression were 3-5%, panic without agoraphobia 0.4%, phobia unspecified 0.5-%, and anxiety not-otherwise-specified 0.3-6.5%. We found significant variability in anxiety disorders in the studies in selected population groups. The variability could also have been affected by methodological factors within each study. This study provides a broad overview of the prevalence of anxiety disorders in Malaysia. More research is required to develop diagnostic instruments that are validated for local use and comparable with international standards. Reliable prevalence estimates are lacking within certain groups, e.g. those in rural, indigenous, migrant population groups and those exposed to natural disasters. Copyright © 2016 Elsevier B.V. All rights reserved.

Applied Prevalence Ratio estimation with different Regression models: An example from a cross-national study on substance use research.

PubMed

Espelt, Albert; Marí-Dell'Olmo, Marc; Penelo, Eva; Bosque-Prous, Marina

2016-06-14

To examine the differences between Prevalence Ratio (PR) and Odds Ratio (OR) in a cross-sectional study and to provide tools to calculate PR using two statistical packages widely used in substance use research (STATA and R). We used cross-sectional data from 41,263 participants of 16 European countries participating in the Survey on Health, Ageing and Retirement in Europe (SHARE). The dependent variable, hazardous drinking, was calculated using the Alcohol Use Disorders Identification Test - Consumption (AUDIT-C). The main independent variable was gender. Other variables used were: age, educational level and country of residence. PR of hazardous drinking in men with relation to women was estimated using Mantel-Haenszel method, log-binomial regression models and poisson regression models with robust variance. These estimations were compared to the OR calculated using logistic regression models. Prevalence of hazardous drinkers varied among countries. Generally, men have higher prevalence of hazardous drinking than women [PR=1.43 (1.38-1.47)]. Estimated PR was identical independently of the method and the statistical package used. However, OR overestimated PR, depending on the prevalence of hazardous drinking in the country. In cross-sectional studies, where comparisons between countries with differences in the prevalence of the disease or condition are made, it is advisable to use PR instead of OR.

Cigarette Smoking Among Inmates by Race/Ethnicity: Impact of Excluding African American Young Adult Men From National Prevalence Estimates.

PubMed

Kennedy, Sara M; Sharapova, Saida R; Beasley, Derrick D; Hsia, Jason

2016-04-01

Cigarette smoking prevalence is more than two times greater among incarcerated adults, a population usually excluded from national health surveys. African American young adult (18-25) men are less likely to smoke cigarettes than their white counterparts. However, they are two and a-half-times more likely to be incarcerated. This study estimated smoking prevalence with noninstitutionalized and incarcerated samples combined to determine if excluding incarcerated adults impacts smoking prevalence for certain populations. The Bureau of Justice Statistics last fielded the Survey of Inmates in State and Federal Correction Facilities in 2003-2004. We combined data from Survey of Inmates in State and Federal Correction Facilities (n = 17 910) and the 2003 and 2004 National Health Interview Survey (n = 61 470) to calculate combined cigarette smoking estimates by race/ethnicity, sex, and age. Inmates represented the greatest proportion of smokers among African American men. Among African American young adult men, inmates represented 15.2% of all smokers in the combined population, compared to 2.0% among white young adult men. Cigarette smoking prevalence was 17.6% in the noninstitutionalized population of young adult African American men and 19.7% in the combined population. Among white young adult men, cigarette smoking prevalence was 29.8% in the noninstitutionalized population, and 30.2% in the combined population. There was little difference in estimates among women. The exclusion of incarcerated African American young adult men may result in a small underestimation of cigarette smoking prevalence in this population. Increasing access to smoking cessation support among inmates may reduce smoking prevalence in disproportionately incarcerated segments of the US population. The exclusion of incarcerated adults from national survey data should be considered when examining differences in cigarette smoking prevalence estimates between African American and white young adult men

Prevalence and risk factors of Coxiella burnetii seropositivity in Danish beef and dairy cattle at slaughter adjusted for test uncertainty.

PubMed

Paul, Suman; Agger, Jens F; Agerholm, Jørgen S; Markussen, Bo

2014-03-01

Antibodies to Coxiella burnetii have been found in the Danish dairy cattle population with high levels of herd and within herd seroprevalences. However, the prevalence of antibodies to C. burnetii in Danish beef cattle remains unknown. The objectives of this study were to (1) estimate the prevalence and (2) identify risk factors associated with C. burnetii seropositivity in Danish beef and dairy cattle based on sampling at slaughter. Eight hundred blood samples from slaughtered cattle were collected from six Danish slaughter houses from August to October 2012 following a random sampling procedure. Blood samples were tested by a commercially available C. burnetii antibody ELISA kit. A sample was defined positive if the sample-to-positive ratio was greater than or equal to 40. Animal and herd information were extracted from the Danish Cattle Database. Apparent (AP) and true prevalences (TPs) specific for breed, breed groups, gender and herd type; and breed-specific true prevalences with a random effect of breed was estimated in a Bayesian framework. A Bayesian logistic regression model was used to identify risk factors of C. burnetii seropositivity. Test sensitivity and specificity estimates from a previous study involving Danish dairy cattle were used to generate prior information. The prevalence was significantly higher in dairy breeds (AP=9.11%; TP=9.45%) than in beef breeds (AP=4.32%; TP=3.54%), in females (AP=9.10%; TP=9.40%) than in males (AP=3.62%; TP=2.61%) and in dairy herds (AP=15.10%; TP=16.67%) compared to beef herds (AP=4.54%; TP=3.66%). The Bayesian logistic regression model identified breed group along with age, and number of movements as contributors for C. burnetii seropositivity. The risk of seropositivity increased with age and increasing number of movements between herds. Results indicate that seroprevalence of C. burnetii is lower in cattle sent for slaughter than in Danish dairy cows in production units. A greater proportion of this prevalence

Estimated prevalence of erosive tooth wear in permanent teeth of children and adolescents: an epidemiological systematic review and meta-regression analysis.

PubMed

Salas, M M S; Nascimento, G G; Huysmans, M C; Demarco, F F

2015-01-01

The main purpose of this systematic review was to estimate the prevalence of dental erosion in permanent teeth of children and adolescents. An electronic search was performed up to and including March 2014. Eligibility criteria included population-based studies in permanent teeth of children and adolescents aged 8-19-year-old reporting the prevalence or data that allowed the calculation of prevalence rates of tooth erosion. Data collection assessed information regarding geographic location, type of index used for clinical examination, sample size, year of publication, age, examined teeth and tissue exposure. The estimated prevalence of erosive wear was determined, followed by a meta-regression analysis. Twenty-two papers were included in the systematic review. The overall estimated prevalence of tooth erosion was 30.4% (95%IC 23.8-37.0). In the multivariate meta-regression model use of the Tooth Wear Index for clinical examination, studies with sample smaller than 1000 subjects and those conducted in the Middle East and Africa remained associated with higher dental erosion prevalence rates. Our results demonstrated that the estimated prevalence of erosive wear in permanent teeth of children and adolescents is 30.4% with high heterogeneity between studies. Additionally, the correct choice of a clinical index for dental erosion detection and the geographic location play an important role for the large variability of erosive tooth wear in permanent teeth of children and adolescents. The prevalence of tooth erosion observed in permanent teeth of children and adolescents was considerable high. Our results demonstrated that prevalence rate of erosive wear was influenced by methodological and diagnosis factors. When tooth erosion is assessed, the clinical index should be considered. Copyright © 2014 Elsevier Ltd. All rights reserved.

Estimating the impact of grouping misclassification on risk ...

EPA Pesticide Factsheets

Environmental health risk assessments of chemical mixtures that rely on component approaches often begin by grouping the chemicals of concern according to toxicological similarity. Approaches that assume dose addition typically are used for groups of similarly-acting chemicals and those that assume response addition are used for groups of independently acting chemicals. Grouping criteria for similarity can include a common adverse outcome pathway (AOP) and similarly shaped dose-response curves, with the latter used in the relative potency factor (RPF) method for estimating mixture response. Independence of toxic action is generally assumed if there is evidence that the chemicals act by different mechanisms. Several questions arise about the potential for misclassification error in the mixture risk prediction. If a common AOP has been established, how much error could there be if the same dose-response curve shape is assumed for all chemicals, when the shapes truly differ and, conversely, what is the error potential if different shapes are assumed when they are not? In particular, how do those concerns impact the choice of index chemical and uncertainty of the RPF-estimated mixture response? What is the quantitative impact if dose additivity is assumed when complete or partial independence actually holds and vice versa? These concepts and implications will be presented with numerical examples in the context of uncertainty of the RPF-estimated mixture response,

Estimating a test's accuracy using tailored meta-analysis-How setting-specific data may aid study selection.

PubMed

Willis, Brian H; Hyde, Christopher J

2014-05-01

To determine a plausible estimate for a test's performance in a specific setting using a new method for selecting studies. It is shown how routine data from practice may be used to define an "applicable region" for studies in receiver operating characteristic space. After qualitative appraisal, studies are selected based on the probability that their study accuracy estimates arose from parameters lying in this applicable region. Three methods for calculating these probabilities are developed and used to tailor the selection of studies for meta-analysis. The Pap test applied to the UK National Health Service (NHS) Cervical Screening Programme provides a case example. The meta-analysis for the Pap test included 68 studies, but at most 17 studies were considered applicable to the NHS. For conventional meta-analysis, the sensitivity and specificity (with 95% confidence intervals) were estimated to be 72.8% (65.8, 78.8) and 75.4% (68.1, 81.5) compared with 50.9% (35.8, 66.0) and 98.0% (95.4, 99.1) from tailored meta-analysis using a binomial method for selection. Thus, for a cervical intraepithelial neoplasia (CIN) 1 prevalence of 2.2%, the post-test probability for CIN 1 would increase from 6.2% to 36.6% between the two methods of meta-analysis. Tailored meta-analysis provides a method for augmenting study selection based on the study's applicability to a setting. As such, the summary estimate is more likely to be plausible for a setting and could improve diagnostic prediction in practice. Copyright © 2014 Elsevier Inc. All rights reserved.

The prevalence of musculoskeletal symptoms in the construction industry: a systematic review and meta-analysis.

PubMed

Umer, Waleed; Antwi-Afari, Maxwell F; Li, Heng; Szeto, Grace P Y; Wong, Arnold Y L

2018-02-01

Although individual studies have reported high prevalence of musculoskeletal symptoms (MSS) among construction workers, no systematic review has summarized their prevalence rates. Accordingly, this systematic review/meta-analysis aimed to synthesize MSS prevalence in different construction trades, gender and age groups, which may help develop specific ergonomic interventions. Nine databases were searched for articles related to the research objective. Two reviewers independently screened citations, extracted information and conducted quality assessment of the included studies. Meta-analyses were conducted on clinical and statistical homogenous data. Thirty-five out of 1130 potential citations were included reporting diverse types of period prevalence and case definitions. Only the 1-year prevalence rates of MSS (defined as at least one episode of pain/MSS in the last year) at nine anatomical regions had sufficient homogeneous data for meta-analysis. Specifically, the 1-year prevalence of MSS was 51.1% for lower back, 37.2% for knee, 32.4% for shoulder, 30.4% for wrist, 24.4% for neck, 24.0% for ankle/foot, 20.3% for elbow, 19.8% for upper back, and 15.1% for hip/thigh. Female workers demonstrated a higher prevalence of MSS while there was insufficient information on the prevalence of trade-specific or age-related MSS. The quality assessments revealed that many included studies estimated prevalence solely based on self-reported data, and did not report non-respondents' characteristics. Lumbar, knee, shoulder, and wrist MSS are the most common symptoms among construction workers. Future studies should standardize the reporting of period prevalence of MSS in different construction trades to allow meta-analyses and to develop relevant MSS prevention program.

[Direct costs of diabetes mellitus in Germany: first estimation of the differences related to educational level].

PubMed

Korber, K; Teuner, C M; Lampert, T; Mielck, A; Leidl, R

2013-12-01

There are many studies on health inequalities, but these are rarely combined with cost-of-illness analyses. If the cost-of-illness were to be calculated for the individual status groups, it would be possible to assess the economic potential of preventive measures aimed specifically at people from low status groups. The objective of this article is to demonstrate for the first time the preventive potential by taking the example of diabetes mellitus (DM) from an economic perspective. Based on a systematic literature review, the average direct costs per patient with DM were assessed. Then, the prevalence of DM among adults with different educational levels was estimated based on the nationwide survey 'German Health Update' (GEDA), conducted by the Robert Koch-Institute in Germany in 2009. Finally, the cost and prevalence data were used to calculate the direct costs for each educational level. The direct costs of DM amount to about 13.1 billion € per year; about 35% of these costs can be attributed to patients with a low educational level. Thus, their share of the total costs is about 67% higher than their share of the total population. If the prevalence in the group with 'low educational level' (14.8%) could be reduced to the prevalence in the group with 'middle educational level' (7.9%), this would save about 2.2 billion (about 16.5%) € of direct costs. The analysis provides a first estimate of the potential savings from an effective status specific prevention programme. However, the direct costs per patient used were only an average for all people with DM, as a breakdown by educational level was not available. Since education can also affect health behaviour and compliance, which are also determinants of cost, the analyses presented here are probably conservative. © Georg Thieme Verlag KG Stuttgart · New York.

A Bayesian evidence synthesis approach to estimate disease prevalence in hard-to-reach populations: hepatitis C in New York City.

PubMed

Tan, Sarah; Makela, Susanna; Heller, Daliah; Konty, Kevin; Balter, Sharon; Zheng, Tian; Stark, James H

2018-06-01

Existing methods to estimate the prevalence of chronic hepatitis C (HCV) in New York City (NYC) are limited in scope and fail to assess hard-to-reach subpopulations with highest risk such as injecting drug users (IDUs). To address these limitations, we employ a Bayesian multi-parameter evidence synthesis model to systematically combine multiple sources of data, account for bias in certain data sources, and provide unbiased HCV prevalence estimates with associated uncertainty. Our approach improves on previous estimates by explicitly accounting for injecting drug use and including data from high-risk subpopulations such as the incarcerated, and is more inclusive, utilizing ten NYC data sources. In addition, we derive two new equations to allow age at first injecting drug use data for former and current IDUs to be incorporated into the Bayesian evidence synthesis, a first for this type of model. Our estimated overall HCV prevalence as of 2012 among NYC adults aged 20-59 years is 2.78% (95% CI 2.61-2.94%), which represents between 124,900 and 140,000 chronic HCV cases. These estimates suggest that HCV prevalence in NYC is higher than previously indicated from household surveys (2.2%) and the surveillance system (2.37%), and that HCV transmission is increasing among young injecting adults in NYC. An ancillary benefit from our results is an estimate of current IDUs aged 20-59 in NYC: 0.58% or 27,600 individuals. Copyright © 2018 Elsevier B.V. All rights reserved.

Prevalence of upper limb disorders among female librarians.

PubMed

Pandy, R

2013-09-01

Work as a librarian involves exposure to potential risk factors for developing upper limb disorders. The prevalence of upper limb symptoms has, however, not previously been assessed in this occupational group. To estimate the 7-day and annual prevalence of self-reported neck and upper limb symptoms in librarians and to examine associations with specific tasks and ergonomic risk factors. A cross-sectional study using components of the standardized Nordic questionnaire. The study population consisted of librarians employed by a large local authority, and data collection was by means of a self-administered questionnaire. from studies on keyboard workers and on the general population were used as comparators. The 7-day prevalence of self-reported neck and upper limb pain in female librarians was 42% (95% confidence interval (CI) 33.7-50.5) and the annual prevalence was 65% (95% CI 56.6-72.8). The prevalence of reported wrist and hand pain increased with increased working involving a wide thumb-index span (P < 0.05) with a significant linear trend in prevalence with increasing exposure (P < 0.01). There was a strong association between reporting hand and/or wrist pain and awareness of work-related upper limb disorder (P < 0.05). The annual prevalence of self-reported upper limb symptoms among female librarians was high, but there was insufficient evidence to confirm whether the prevalence was higher than in the general population or among keyboard workers. Working with a wide thumb-index span was associated with reporting upper limb symptoms.

Reliability of CKD-EPI predictive equation in estimating chronic kidney disease prevalence in the Croatian endemic nephropathy area.

PubMed

Fuček, Mirjana; Dika, Živka; Karanović, Sandra; Vuković Brinar, Ivana; Premužić, Vedran; Kos, Jelena; Cvitković, Ante; Mišić, Maja; Samardžić, Josip; Rogić, Dunja; Jelaković, Bojan

2018-02-15

Chronic kidney disease (CKD) is a significant public health problem and it is not possible to precisely predict its progression to terminal renal failure. According to current guidelines, CKD stages are classified based on the estimated glomerular filtration rate (eGFR) and albuminuria. Aims of this study were to determine the reliability of predictive equation in estimation of CKD prevalence in Croatian areas with endemic nephropathy (EN), compare the results with non-endemic areas, and to determine if the prevalence of CKD stages 3-5 was increased in subjects with EN. A total of 1573 inhabitants of the Croatian Posavina rural area from 6 endemic and 3 non-endemic villages were enrolled. Participants were classified according to the modified criteria of the World Health Organization for EN. Estimated GFR was calculated using Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI). The results showed a very high CKD prevalence in the Croatian rural area (19%). CKD prevalence was significantly higher in EN then in non EN villages with the lowest eGFR value in diseased subgroup. eGFR correlated significantly with the diagnosis of EN. Kidney function assessment using CKD-EPI predictive equation proved to be a good marker in differentiating the study subgroups, remained as one of the diagnostic criteria for EN.

Sensitivity and specificity of the method used for ascertainment of healthcare-associated infections in the second Slovenian national prevalence survey.

PubMed

Serdt, Mojca; Lejko Zupanc, Tatjana; Korošec, Aleš; Klavs, Irena

2016-12-01

The second Slovenian national healthcare-associated infections (HAIs) prevalence survey (SNHPS) was conducted in acute-care hospitals in 2011. The objective was to assess the sensitivity and specificity of the method used for the ascertainment of six types of HAIs (bloodstream infections, catheter-associated infections, lower respiratory tract infections, pneumoniae, surgical site infections, and urinary tract infections) in the University Medical Centre Ljubljana (UMCL). A cross-sectional study was conducted in patients surveyed in the SNHPS in the UMCL using a retrospective medical chart review (RMCR) and European HAIs surveillance definitions. Sensitivity and specificity of the method used in the SNHPS using RMCR as a reference was computed for ascertainment of patients with any of the six selected types of HAIs and for individual types of HAIs. Agreement between the SNHPS and RMCR results was analyzed using Cohen's kappa coefficient. 1474 of 1742 (84.6%) patients surveyed in the SNHPS were included in RMCR. The sensitivity of the SNHPS method for detecting any of six HAIs was 90% (95% confidence interval (CI): 81%-95%) and specificity 99% (95% CI: 98%-99%). The sensitivity by type of HAI ranged from 63% (lower respiratory tract infections) to 92% (bloodstream infections). Specificity was at least 99% for all types of HAIs. Agreement between the two data collection approaches for HAIs overall was very good (κ=0.83). The overall sensitivity of SNHPS collection method for ascertaining HAIs overall was high and the specificity was very high. This suggests that the estimated prevalence of HAIs in the SNHPS was credible.

Using Relative Statistics and Approximate Disease Prevalence to Compare Screening Tests.

PubMed

Samuelson, Frank; Abbey, Craig

2016-11-01

Schatzkin et al. and other authors demonstrated that the ratios of some conditional statistics such as the true positive fraction are equal to the ratios of unconditional statistics, such as disease detection rates, and therefore we can calculate these ratios between two screening tests on the same population even if negative test patients are not followed with a reference procedure and the true and false negative rates are unknown. We demonstrate that this same property applies to an expected utility metric. We also demonstrate that while simple estimates of relative specificities and relative areas under ROC curves (AUC) do depend on the unknown negative rates, we can write these ratios in terms of disease prevalence, and the dependence of these ratios on a posited prevalence is often weak particularly if that prevalence is small or the performance of the two screening tests is similar. Therefore we can estimate relative specificity or AUC with little loss of accuracy, if we use an approximate value of disease prevalence.

Prevalence of Knee Osteoarthritis in 100 Athletically Active Veteran Soccer Players Compared With a Matched Group of 100 Military Personnel.

PubMed

Paxinos, Odysseas; Karavasili, Alexandra; Delimpasis, Georgios; Stathi, Afroditi

2016-06-01

Although knee injuries in professional soccer (football) have been extensively studied, the prevalence of knee osteoarthritis (OA) in veteran players is not well documented. To investigate the prevalence of knee OA in retired professional soccer players in comparison with a group of athletically active military personnel. Cross-sectional study; Level of evidence, 3. A group of 100 veteran Greek soccer players aged 35 to 55 years (mean [±SD] age, 46.90 ± 5.9 years) were examined for knee OA and were administered the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire. A matched group of 100 athletically active military personnel served as a comparison group. The sonographic prevalence of OA was significantly higher in the veteran soccer group (52%) than in the military group (33%) (n = 200; P = .010). This difference remained significant even after excluding participants with a history of knee surgery (44.1% vs 25.3%, respectively) (n = 151; P = .010). Femoral cartilage thickness was similar between the 2 groups (P = .473), while altered knee alignment had no effect on the prevalence of OA (P = .740). With the exception of perceived pain being more prevalent in the military group, there were no other statistically significant differences between the 2 groups in KOOS values. Veteran soccer players had a higher sonographic prevalence of knee OA but better pain scores than a matched group of athletically active military personnel. © 2016 The Author(s).

Interpolation between spatial frameworks: an application of process convolution to estimating neighbourhood disease prevalence.

PubMed

Congdon, Peter

2014-04-01

Health data may be collected across one spatial framework (e.g. health provider agencies), but contrasts in health over another spatial framework (neighbourhoods) may be of policy interest. In the UK, population prevalence totals for chronic diseases are provided for populations served by general practitioner practices, but not for neighbourhoods (small areas of circa 1500 people), raising the question whether data for one framework can be used to provide spatially interpolated estimates of disease prevalence for the other. A discrete process convolution is applied to this end and has advantages when there are a relatively large number of area units in one or other framework. Additionally, the interpolation is modified to take account of the observed neighbourhood indicators (e.g. hospitalisation rates) of neighbourhood disease prevalence. These are reflective indicators of neighbourhood prevalence viewed as a latent construct. An illustrative application is to prevalence of psychosis in northeast London, containing 190 general practitioner practices and 562 neighbourhoods, including an assessment of sensitivity to kernel choice (e.g. normal vs exponential). This application illustrates how a zero-inflated Poisson can be used as the likelihood model for a reflective indicator.

Association between Ambient Air Pollution and Asthma Prevalence in Different Population Groups Residing in Eastern Texas, USA.

PubMed

Gorai, Amit Kr; Tchounwou, Paul B; Tuluri, Francis

2016-03-29

Air pollution has been an on-going research focus due to its detrimental impact on human health. However, its specific effects on asthma prevalence in different age groups, genders and races are not well understood. Thus, the present study was designed to examine the association between selected air pollutants and asthma prevalence in different population groups during 2010 in the eastern part of Texas, USA.The pollutants considered were particulate matter (PM2.5 with an aerodynamic diameter less than 2.5 micrometers) and surface ozone. The population groups were categorized based on age, gender, and race. County-wise asthma hospital discharge data for different age, gender, and racial groups were obtained from Texas Asthma Control Program, Office of Surveillance, Evaluation and Research, Texas Department of State Health Services. The annual means of the air pollutants were obtained from the United States Environmental Protection Agency (U.S. EPA)'s air quality system data mart program. Pearson correlation analyzes were conducted to examine the relationship between the annual mean concentrations of pollutants and asthma discharge rates (ADR) for different age groups, genders, and races. The results reveal that there is no significant association or relationship between ADR and exposure of air pollutants (PM2.5, and O₃). The study results showed a positive correlation between PM2.5 and ADR and a negative correlation between ADR and ozone in most of the cases. These correlations were not statistically significant, and can be better explained by considering the local weather conditions. The research findings facilitate identification of hotspots for controlling the most affected populations from further environmental exposure to air pollution, and for preventing or reducing the health impacts.

The prevalence of peripheral arterial disease (PAD) and PAD risk factors among different ethnic groups in the US population.

PubMed

Aponte, Judith

2012-06-01

The National Health and Nutrition Examination Survey (NHANES) 2003-2004 data set was utilized to examine and compare trends and differences in PAD-related risk factor variables among 5 different ethnic/racial groups. The sample included individuals 40 years and older with PAD and of the ethnic/racial groups: Mexican American, Other Hispanic, Non-Hispanic White, Non-Hispanic Black, and Other/Multiracial. Two demographic variables (age and gender) and 4 PAD-risk factors (hypertension [HTN], systolic blood pressure [SBP], and diastolic blood pressure [DBP]), dyslipidemia, high-density lipoprotein [HDL] and low-density lipoprotein [LDL], diabetes, and cigarette smoking) were examined for each group. The study design conducted was descriptive using the NHANES 2003-2004 secondary data set. Raw data were weighted. Descriptive statistics were measured, Chi-squares were compared, and Phi-coefficients were measured for association using SAS version 9.1 and SUDAAN 10.0. The group with the highest prevalence of PAD are females 40-50 years of age, and the ethnic group with PAD who have the highest risk for PAD-related risk factors are Non-Hispanic Black. Through Chi-square significant differences (P=0.00001-0.03874) between specific ethnic groups for all four PAD-related risk factors (i.e., HTN, dyslipidemia, diabetes and cigarette smoking). All of the associations between the prevalence of HTN, dyslipidemia, diabetes, or cigarette smoking and ethnicity were statistically significant (P=<0.0001). Overall differences exist among the different ethnic groups. Copyright © 2012 Society for Vascular Nursing, Inc. Published by Mosby, Inc. All rights reserved.

Prevalence of victimization and exposure to violence in a sample of Hispanic Americans: a research note.

PubMed

Miller, Holly Ventura; Lopez, Kristina M

2015-05-01

Research on the growing U.S. Hispanic population has increased in recent years, although much of this work has examined differences between the foreign- and native-born or between Hispanics and non-Hispanics. Fewer studies have explored within-group differences (Mexican vs. Puerto Rican vs. Cuban, etc.) and none have assessed variability in the prevalence of victimization across these diverse groups. Unfortunately, the available evidence is somewhat inconclusive regarding the prevalence of victimization among Hispanics and relative to other demographic groups such as Whites and Blacks. This study first aims to provide clarification as to the prevalence of Hispanic victimization relative to non-Hispanic Whites (NHW) and non-Hispanic Blacks (NHB). Then, we assess within-group differences for the Hispanic subsample for each of the victimization measures. Using Wave IV of the National Longitudinal Study of Adolescent Health (Add Health), we estimate the prevalence of various forms of criminal victimization and exposure to violence for Hispanics, NHW, and NHB. Results suggest that significant differences exist between Hispanics and both NHW and NHB. More specifically, Hispanics were less likely to report most of the victimization outcomes than either group. Significant differences in victimization were also observed between Hispanic subgroups. Generally, Mexicans and Puerto Ricans were most likely to report victimization whereas Cubans and Chicanos (with the exception of property crime) were least likely to report victimization. © The Author(s) 2014.

How social information can improve estimation accuracy in human groups.

PubMed

Jayles, Bertrand; Kim, Hye-Rin; Escobedo, Ramón; Cezera, Stéphane; Blanchet, Adrien; Kameda, Tatsuya; Sire, Clément; Theraulaz, Guy

2017-11-21

In our digital and connected societies, the development of social networks, online shopping, and reputation systems raises the questions of how individuals use social information and how it affects their decisions. We report experiments performed in France and Japan, in which subjects could update their estimates after having received information from other subjects. We measure and model the impact of this social information at individual and collective scales. We observe and justify that, when individuals have little prior knowledge about a quantity, the distribution of the logarithm of their estimates is close to a Cauchy distribution. We find that social influence helps the group improve its properly defined collective accuracy. We quantify the improvement of the group estimation when additional controlled and reliable information is provided, unbeknownst to the subjects. We show that subjects' sensitivity to social influence permits us to define five robust behavioral traits and increases with the difference between personal and group estimates. We then use our data to build and calibrate a model of collective estimation to analyze the impact on the group performance of the quantity and quality of information received by individuals. The model quantitatively reproduces the distributions of estimates and the improvement of collective performance and accuracy observed in our experiments. Finally, our model predicts that providing a moderate amount of incorrect information to individuals can counterbalance the human cognitive bias to systematically underestimate quantities and thereby improve collective performance. Copyright © 2017 the Author(s). Published by PNAS.

How social information can improve estimation accuracy in human groups

PubMed Central

Jayles, Bertrand; Kim, Hye-rin; Cezera, Stéphane; Blanchet, Adrien; Kameda, Tatsuya; Sire, Clément; Theraulaz, Guy

2017-01-01

In our digital and connected societies, the development of social networks, online shopping, and reputation systems raises the questions of how individuals use social information and how it affects their decisions. We report experiments performed in France and Japan, in which subjects could update their estimates after having received information from other subjects. We measure and model the impact of this social information at individual and collective scales. We observe and justify that, when individuals have little prior knowledge about a quantity, the distribution of the logarithm of their estimates is close to a Cauchy distribution. We find that social influence helps the group improve its properly defined collective accuracy. We quantify the improvement of the group estimation when additional controlled and reliable information is provided, unbeknownst to the subjects. We show that subjects’ sensitivity to social influence permits us to define five robust behavioral traits and increases with the difference between personal and group estimates. We then use our data to build and calibrate a model of collective estimation to analyze the impact on the group performance of the quantity and quality of information received by individuals. The model quantitatively reproduces the distributions of estimates and the improvement of collective performance and accuracy observed in our experiments. Finally, our model predicts that providing a moderate amount of incorrect information to individuals can counterbalance the human cognitive bias to systematically underestimate quantities and thereby improve collective performance. PMID:29118142

Prevalence of face recognition deficits in middle childhood.

PubMed

Bennetts, Rachel J; Murray, Ebony; Boyce, Tian; Bate, Sarah

2017-02-01

Approximately 2-2.5% of the adult population is believed to show severe difficulties with face recognition, in the absence of any neurological injury-a condition known as developmental prosopagnosia (DP). However, to date no research has attempted to estimate the prevalence of face recognition deficits in children, possibly because there are very few child-friendly, well-validated tests of face recognition. In the current study, we examined face and object recognition in a group of primary school children (aged 5-11 years), to establish whether our tests were suitable for children and to provide an estimate of face recognition difficulties in children. In Experiment 1 (n = 184), children completed a pre-existing test of child face memory, the Cambridge Face Memory Test-Kids (CFMT-K), and a bicycle test with the same format. In Experiment 2 (n = 413), children completed three-alternative forced-choice matching tasks with faces and bicycles. All tests showed good psychometric properties. The face and bicycle tests were well matched for difficulty and showed a similar developmental trajectory. Neither the memory nor the matching tests were suitable to detect impairments in the youngest groups of children, but both tests appear suitable to screen for face recognition problems in middle childhood. In the current sample, 1.2-5.2% of children showed difficulties with face recognition; 1.2-4% showed face-specific difficulties-that is, poor face recognition with typical object recognition abilities. This is somewhat higher than previous adult estimates: It is possible that face matching tests overestimate the prevalence of face recognition difficulties in children; alternatively, some children may "outgrow" face recognition difficulties.

Justifying group-specific common morality.

PubMed

Strong, Carson

2008-01-01

Some defenders of the view that there is a common morality have conceived such morality as being universal, in the sense of extending across all cultures and times. Those who deny the existence of such a common morality often argue that the universality claim is implausible. Defense of common morality must take account of the distinction between descriptive and normative claims that there is a common morality. This essay considers these claims separately and identifies the nature of the arguments for each claim. It argues that the claim that there is a universal common morality in the descriptive sense has not been successfully defended to date. It maintains that the claim that there is a common morality in the normative sense need not be understood as universalist. This paper advocates the concept of group specific common morality, including country-specific versions. It suggests that both the descriptive and the normative claims that there are country-specific common moralities are plausible, and that a country-specific normative common morality could provide the basis for a country's bioethics.

Prevalence, Variability and Bioconcentration of Saxitoxin-Group in Different Marine Species Present in the Food Chain

PubMed Central

Oyaneder Terrazas, Javiera; Contreras, Héctor R.; García, Carlos

2017-01-01

The saxitoxin-group (STX-group) corresponds to toxic metabolites produced by cyanobacteria and dinoflagellates of the genera Alexandrium, Gymnodinium, and Pyrodinium. Over the last decade, it has been possible to extrapolate the areas contaminated with the STX-group worldwide, including Chile, a phenomenon that has affected ≈35% of the Southern Pacific coast territory, generating a high economic impact. The objective of this research was to study the toxicity of the STX-group in all aquatic organisms (bivalves, algae, echinoderms, crustaceans, tunicates, cephalopods, gastropods, and fish) present in areas with a variable presence of harmful algal blooms (HABs). Then, the toxic profiles of each species and dose of STX equivalents ingested by a 60 kg person from 400 g of shellfish were determined to establish the health risk assessment. The toxins with the highest prevalence detected were gonyautoxin-4/1 (GTX4/GTX1), gonyautoxin-3/2 (GTX3/GTX2), neosaxitoxin (neoSTX), decarbamoylsaxitoxin (dcSTX), and saxitoxin (STX), with average concentrations of 400, 2800, 280, 200, and 2000 µg kg−1 respectively, a species-specific variability, dependent on the evaluated tissue, which demonstrates the biotransformation of the analogues in the trophic transfer with a predominance of α-epimers in all toxic profiles. The identification in multiple vectors, as well as in unregulated species, suggests that a risk assessment and risk management update are required; also, chemical and specific analyses for the detection of all analogues associated with the STX-group need to be established. PMID:28604648

Prevalence, severity and risk factors of asthma, rhinitis and eczema in a large group of Chinese schoolchildren.

PubMed

Song, Ning; Shamssain, Mohammed; Mohammed, Shamssain; Zhang, Jin; Wu, Jianling; Fu, Chunling; Hao, Shuting; Guan, Jitao; Yan, Xixin

2014-04-01

There is a lack of information on the prevalence, severity and risk factors of asthma, rhinitis and eczema in Chinese children. To establish baseline data for a major longitudinal study of factors affecting asthma, rhinitis and eczema in a large group of children from the industrialized city of Shijiazhuang, China. We used the International Study of Asthma and Allergies in Childhood questionnaire and studied 10 338 children, ages 6-18, from Shijiazhuang. The prevalence of childhood asthma, rhinitis and eczema is 1.2%, 13.5% and 11.8%, respectively. Boys had higher prevalence of these conditions than girls and younger children had higher prevalence of asthma and eczema but lower prevalence of rhinitis than older children. Breastfed children had lower prevalence of asthma and rhinitis, but not eczema, than non-breastfed children. Overweight children had higher prevalence of asthma and rhinitis than those who were not overweight. Children exposed to paternal smoking had higher prevalence of rhinitis and eczema than those not exposed; children exposed to pets had higher prevalence of asthma and rhinitis than those not exposed. The prevalence of asthma in this study group is low, but the prevalence of rhinitis is high, and could be considered a major public health problem. The prevalence of asthma, rhinitis and eczema is generally higher in boys and younger children generally have higher prevalence of asthma and eczema but lower prevalence of rhinitis. Exposure to pets is a risk factor for rhinitis, being overweight is a risk factor for asthma and rhinitis, and exposure to parental smoking is a risk factor for asthma, rhinitis and eczema in these children.

Utility of Capture-Recapture Methodology to Estimate Prevalence of Congenital Heart Defects Among Adolescents in 11 New York State Counties: 2008 to 2010.

PubMed

Akkaya-Hocagil, Tugba; Hsu, Wan-Hsiang; Sommerhalter, Kristin; McGarry, Claire; Van Zutphen, Alissa

2017-11-01

Congenital heart defects (CHDs) are the most common birth defects in the United States, and the population of individuals living with CHDs is growing. Though CHD prevalence in infancy has been well characterized, better prevalence estimates among children and adolescents in the United States are still needed. We used capture-recapture methods to estimate CHD prevalence among adolescents residing in 11 New York counties. The three data sources used for analysis included Statewide Planning and Research Cooperative System (SPARCS) hospital inpatient records, SPARCS outpatient records, and medical records provided by seven pediatric congenital cardiac clinics from 2008 to 2010. Bayesian log-linear models were fit using the R package Conting to account for dataset dependencies and heterogeneous catchability. A total of 2537 adolescent CHD cases were captured in our three data sources. Forty-four cases were identified in all data sources, 283 cases were identified in two of three data sources, and 2210 cases were identified in a single data source. The final model yielded an estimated total adolescent CHD population of 3845, indicating that 66% of the cases in the catchment area were identified in the case-identifying data sources. Based on 2010 Census estimates, we estimated adolescent CHD prevalence as 6.4 CHD cases per 1000 adolescents (95% confidence interval: 6.2-6.6). We used capture-recapture methodology with a population-based surveillance system in New York to estimate CHD prevalence among adolescents. Future research incorporating additional data sources may improve prevalence estimates in this population. Birth Defects Research 109:1423-1429, 2017.© 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Temperature-Dependent Estimation of Gibbs Energies Using an Updated Group-Contribution Method.

PubMed

Du, Bin; Zhang, Zhen; Grubner, Sharon; Yurkovich, James T; Palsson, Bernhard O; Zielinski, Daniel C

2018-06-05

Reaction-equilibrium constants determine the metabolite concentrations necessary to drive flux through metabolic pathways. Group-contribution methods offer a way to estimate reaction-equilibrium constants at wide coverage across the metabolic network. Here, we present an updated group-contribution method with 1) additional curated thermodynamic data used in fitting and 2) capabilities to calculate equilibrium constants as a function of temperature. We first collected and curated aqueous thermodynamic data, including reaction-equilibrium constants, enthalpies of reaction, Gibbs free energies of formation, enthalpies of formation, entropy changes of formation of compounds, and proton- and metal-ion-binding constants. Next, we formulated the calculation of equilibrium constants as a function of temperature and calculated the standard entropy change of formation (Δ f S ∘ ) using a model based on molecular properties. The median absolute error in estimating Δ f S ∘ was 0.013 kJ/K/mol. We also estimated magnesium binding constants for 618 compounds using a linear regression model validated against measured data. We demonstrate the improved performance of the current method (8.17 kJ/mol in median absolute residual) over the current state-of-the-art method (11.47 kJ/mol) in estimating the 185 new reactions added in this work. The efforts here fill in gaps for thermodynamic calculations under various conditions, specifically different temperatures and metal-ion concentrations. These, to our knowledge, new capabilities empower the study of thermodynamic driving forces underlying the metabolic function of organisms living under diverse conditions. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Estimated prevalence of compulsive buying in Germany and its association with sociodemographic characteristics and depressive symptoms.

PubMed

Mueller, Astrid; Mitchell, James E; Crosby, Ross D; Gefeller, Olaf; Faber, Ronald J; Martin, Alexandra; Bleich, Stefan; Glaesmer, Heide; Exner, Cornelia; de Zwaan, Martina

2010-12-30

The aim of this study was to estimate the prevalence of compulsive buying and its association with sociodemographic characteristics and depressive symptoms in a nationally representative sample of the German population using the validated German version of the Compulsive Buying Scale (CBS; Faber and O'Guinn, 1992) in order to have a direct comparison with U.S. findings. The point prevalence of compulsive buying in the weighted representative sample (N=2,350) was estimated to be 6.9%. This was somewhat higher than the percentage in the American sample assessed in 2004 (5.8%). No significant difference was found between women and men (6.9% and 6.8%, respectively). Age was inversely related to the prevalence of compulsive buying. Individuals with compulsive buying reported more depressive symptoms assessed via the German version of the Brief Patient Health Questionnaire Mood Scale (PHQ-9). Further research on this topic is needed to establish a clearer delineation of when excessive buying is clinically significant and should be treated and how it could be prevented. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

Estimating the Smoking Ban Effects on Smoking Prevalence, Quitting and Cigarette Consumption in a Population Study of Apprentices in Italy.

PubMed

Pieroni, Luca; Muzi, Giacomo; Quercia, Augusto; Lanari, Donatella; Rundo, Carmen; Minelli, Liliana; Salmasi, Luca; dell'Omo, Marco

2015-08-13

We evaluated the effects of the Italian 2005 smoking ban in public places on the prevalence of smoking, quitting and cigarette consumption of young workers. The dataset was obtained from non-computerized registers of medical examinations for a population of workers with apprenticeship contracts residing in the province of Viterbo, Italy, in the period 1996-2007. To estimate the effects of the ban, a segmented regression approach was used, exploiting the discontinuity introduced by the application of the law on apprentices' smoking behavior. It is estimated that the Italian smoking ban generally had no effect on smoking prevalence, quitting ratio, or cigarette consumption of apprentices. However, when the estimates were applied to subpopulations, significant effects were found: -1% in smoking prevalence, +2% in quitting, and -3% in smoking intensity of apprentices with at least a diploma.

Collation and comparison of multi-practice audit data: prevalence and treatment of known diabetes mellitus.

PubMed Central

Khunti, K; Goyder, E; Baker, R

1999-01-01

BACKGROUND: Different methods have been used to determine the prevalence and treatment of diabetes. Despite the large number of studies, previous estimations of prevalence and treatment have been carried out on relatively small numbers of patients, and then in only a few practices in single geographical regions. AIM: To investigate the feasibility of collating data from multi-practice audits organized by primary care audit groups in order to estimate the prevalence and treatment of patients with known diabetes, and to discuss the methodological issues and reasons for variation. METHOD: A postal questionnaire survey of all primary care audit groups in England and Wales that had conducted a multi-practice audit of diabetes between 1993-1995. Prevalence rates and patterns of diabetic care were compared with other community-based surveys of known diabetes from 1986-1996 identified on MEDLINE. RESULTS: Twenty-five (43%) audit groups supplied data from multi-practice audits of diabetes. Seven (28%) multi-practice audits involving 259 practices fulfilled the inclusion criteria for prevalence estimation. The overall prevalence of diabetes based on a population of 1,475,512 patients was 1.46% (range between audit groups = 1.18% to 1.66%; chi 2 = 308; df = 6; P < 0.0001). Male to female ratio was 1.15:1. Treatment of diabetes could be ascertained for 10 (40%) audit groups comprising 319 practices. Of these, 23.4% (range = 16.5%-27.4%) were controlled by diet, 48.5% (range = 43.6%-55.8%) were prescribed oral hypoglycaemic drugs, and 28.2% (range = 25.0%-32.4%) were treated with insulin. There were significant variations between audit groups in treatment pattern (chi 2 = 250; df = 18; P < 0.0001). CONCLUSION: Prevalence and treatment rates of diabetes and other chronic diseases can be assessed and compared using data from multi-practice audits. Collation of audit data could improve the precision of quantitative estimates of health status in populations. A standard method of

Estimating the Impact of Raising Prices and Eliminating Discounts on Cigarette Smoking Prevalence in the United States.

PubMed

Marynak, Kristy L; Xu, Xin; Wang, Xu; Holmes, Carissa Baker; Tynan, Michael A; Pechacek, Terry

2016-01-01

The average retail price per pack of cigarettes is less than $6, which is substantially lower than the $10 per-pack target established in 2014 by the Surgeon General to reduce the smoking rate. We estimated the impact of three cigarette pricing scenarios on smoking prevalence among teens aged 12-17 years, young adults aged 18-25 years, and adults aged ≥26 years, by state: (1) $0.94 federal tax increase on cigarettes, as proposed in the fiscal year 2017 President's budget; (2) $10 per-pack retail price, allowing discounts; and (3) $10 per-pack retail price, eliminating discounts. We conducted Monte Carlo simulations to generate point estimates of reductions in cigarette smoking prevalence by state. We found that each price scenario would substantially reduce cigarette smoking prevalence. A $10 per-pack retail price eliminating discounts could result in 637,270 fewer smokers aged 12-17 years; 4,186,954 fewer smokers aged 18-25 years; and 7,722,460 fewer smokers aged ≥26 years. Raising cigarette prices and eliminating discounts could substantially reduce cigarette smoking prevalence as well as smoking-related death and disease.