Prevalence of vitamin A deficiency in isolated geographical pockets of India.

It is unclear whether the survey regions, namely 6 of 1212 Villages and 4 peri-urban areas of 70 municipal wards, were chosen through an unbiased randomization process accounting at least for the socio-economic status. Apparently, the data primarily pertains to the marginalized and lower socio-economic population. The survey was largely conducted during the non winter period, when VAD estimates are usually higher. The authors have also not provided cluster adjusted estimates and 95% confidence intervals. It would therefore be inappropriate to extrapolate the findings from this survey to the entire Aligarh District.