Validity of self-measured waist and hip circumferences: results from a community study in Malaysia

Background: Measures of central adiposity are better predictors of adverse health events than BMI. Nonetheless, BMI is more widely used in health research. One reason for this may be the limited research supporting the self-measurement of waist and hip circumference. The lack of validity studies is particularly acute in Asia. The main objective was to establish the validity of self-measurement of waist and hip circumference in a community setting and the correlation of those measures with BMI, blood pressure, and blood glucose levels. Methods. A community based, cross-sectional survey. A "healthy living expo" at a shopping mall in a rural town on peninsular Malaysia One hundred and thirty six (136) individuals volunteered to participate in the study, 125 of whom met the inclusion criteria. The ethnic distribution of the participants was 80% Chinese, 17% Malay and 3% Indian. Most participants were female (60%), with participants' ages ranging from 18 to 78 years (mean, 47.2). Self and assisted measurements of waist and hip were taken. Blood pressure, non-fasting blood glucose, height, and weight were also measured. Bland Altman plots and Lin's concordance coefficient were used to measure agreement between self and assisted measures. Pearson's correlation was used to examine the association of self and assisted measures with blood pressure, blood glucose, and BMI. Results: There was a downwards bias in self measured waist (-0.81 cm) and hip (-1 cm) circumferences compared with assisted measures. The concordance for the self and assisted measures of waist, hip and the ratio of the two were, respectively,.96,.93, and.84. The correlation between measures of central adiposity and BMI, blood pressure and blood glucose were similar for self and assisted measures. Conclusion: The results provide additional support for the use of self-measurement of waist and hip circumference studies of central adiposity, but is limited by the specificity of the setting. © 2013 Reidpath et al.; licensee BioMed Central Ltd

The relationship between age of smoking initiation and current smoking: an analysis of school surveys in three European countries

Daniel Reidpath - ORCID: 0000-0002-8796-0420 https://orcid.org/0000-0002-8796-0420Item is not available in this repository.Introduction: It is held that younger smoking initiates are more likely to become regular smokers. The definitions of smoking initiation (a puff, part of a cigarette, a whole cigarette) are inconsistent and raise questions about the robustness of the view. We sought to re-examine the relationship using adolescent smoking data from 3 European countries. Methods: A stratified secondary, logistic regression analysis of Global Youth Tobacco Survey data was conducted using a design-based analysis. Subgroup analyses were conducted of 13- to 15-year olds from Latvia (high smoking prevalence), Slovenia (moderate prevalence), and Montenegro (low prevalence) who had initiated smoking. The outcome was current smoking—smoking everyday for the past 30 days, or smoking 10 or more days in the past 30 days. Smoking initiation was operationalized as a single puff of a cigarette, and age of smoking initiation was a derived continuous measure. Results: In Latvia, there was a significant association between age of smoking initiation and current smoking for males (p < .05) and females (p < .001) when smoking was operationalized as smoking every day. It was only significant in female adolescents (p < .001) for smoking 10 or more days. In Slovenia and Montenegro, there was no significant relationship between age of smoking initiation and current smoking for either males or females. Conclusions: The evidence about the relationship between age of smoking initiation and current smoking is not clear. Explanations for the findings may relate to a lack of power, the specificity of the measure, or problems with the theory.https://doi.org/10.1093/ntr/nts17715pubpub