Diagnostic accuracy of anthropometric indices for obesity screening among Asian adolescents

<p><b>INTRODUCTION</b>Weight-and-height-based anthropometric indices have long been used for obesity screening among adolescents.However, the ability of their age-and-sex-specific reference values in classifying adolescent as "obese" in different populations was not fully established. Our study aimed to validate the existing international (BMI-for-age charts from WHO, CDC, IOTF) and local cut-offs [percent weight for height (PWH)] for obesity against body fat percentage, as assessed by 4 skinfolds measurement.</p><p><b>MATERIALS AND METHODS</b>A cross-sectional sample of 6991 adolescents aged 12 to 18 years was measured. All anthropometric measurements were compliant with the internationally accepted protocol. Obesity was defined as percentage body fat greater than or equal to 95 percentile, specific to age and sex. The validity of the existing classification criteria in detecting obesity was evaluated by comparing their respective diagnostic accuracy.</p><p><b>RESULTS</b>Both prevalence of obesity and diagnostic accuracy indices varied by the classification criteria. While all criteria generated very high specificity rates with the lowest being 95%, their sensitivity rates were low ranging from 43% to 71%. Youden's index suggested that CDC and WHO criteria had optimal sensitivity and specificity. ROC analysis showed that overall performance could be improved by refining the existing cut-offs.</p><p><b>CONCLUSIONS</b>Clinical validity of weight-and-height-based classification systems for obesity screening in Asian adolescents is poorer than expected, and this could be improved by refining the existing cut-offs.</p>

Subsyndromal depression in old age: clinical significance and impact in a multi-ethnic community sample of elderly Singaporeans.

OBJECTIVE: This cross-sectional study examined the clinical significance and impact of subsyndromal depression in a sample of elderly people living in the community in Singapore. METHOD: Data were analyzed from a population survey (the Singapore National Mental Health Survey of the Elderly). A total of 1092 respondents from a nationally representative multi-ethnic (Chinese, Malay and Indian) stratified random sample of older adults aged 60 and above were examined for depression using the Geriatric Mental State Examination (GMS). Diagnostic confidence levels of 3-5 indicated a DSM-IV diagnosis of syndromal depression, and 1-2 indicated subsyndromal depression. Other variables included sociodemographic characteristics, psychiatric and medical comorbidities, MMSE, health awareness, health and functional status. RESULTS: Subjects with subsyndromal depression were more likely to have poor socioeconomic status, cognitive impairment, anxiety, and measures of poor mental, physical and functional status compared with non-depressed subjects, and were similar to or worse than syndromal cases. In multivariate analyses that controlled for age, gender, ethnicity, education and several other sociodemographic factors, both subsyndromal and syndromal depression were significantly associated with higher numbers of medical comorbidities, diagnoses of comorbid dementia and anxiety, lower MMSE scores, self-reported mental health problem, functional disability and poor health status. CONCLUSION: In this Asian population, subsydromal depression had the same clinical significance and health impact as syndromal depression, similar to findings in the West.