What are the confounding variables?
It is impossible to judge the validity of this finding without data on the confounding variables.
Given the Indian setting it seems likely that those who are circumcised are Muslims whereas those who are not will be mostly Hindus. As such the circumcised participants are subject to a different sexual mores giving doubt to the conclusion.
Circumcision has long been advocated on the basis of simplistic observational research. While this letter will no doubt give a warm feeling to those who wish to promote circumcision, it provides no basis for inflicting damaging surgery on those who have no disease and cannot give consent.
Conflict of Interest:
Trustee of a charity representing the patients right to an autonomous decision about circumcision.