A larger sample size would have been more appropriate for the study to limit the effect of confounding factors.
A prospective cohort study could have been more appropriate for the study to determine the effect of supplementation of vitamin D on those found to be deficient especially for those with poor glycaemic control. However time constraints did not allow this study design.
Due to time factor the effect of intervention in those with nephropathy was not known.
This study was done only in one season (dry), therefore the effect of seasonal variation on vitamin D cannot be ruled out.
104
Serum parathyroid hormone was not assayed, which might have provided additional information on the biological role of vitamin D.
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