Robust methods are needed to investigate association between white rice consumption and type 2 diabetes

The primary outcome in Hu and colleagues' meta-analysis and systematic review was risk of type 2 diabetes, but the authors did not clearly report their methods, giving it as self reported. 1 Table 2 indicates confirmation of type 2 diabetes by medical practitioners, but. on closer inspection medical testing was carried out only in subjects who self reported diabetes, not in all subjects. The data quality assessment seemed to have been devised by Hu and colleagues and was not a standard tool for critical appraisal. 2 3 The authors reported the results of included studies to be significantly heterogeneous (overall [chi]2=72.2%, P=0.001), but they did not discuss the possible reasons of heterogeneity in their analysis and analysed the pooled findings.