Reader response: Pharmacotherapy for diabetic peripheral neuropathy pain and quality of life: A systematic review

We read with interest the article by Waldfogel et al.¹ The authors suggested that there was a reporting bias regarding pregabalin, due to the number of unpublished studies or studies without results reported on clinicaltrials.gov. Waldfogel et al. searched PubMed and the Cochrane Database for systematic reviews from 2011 to October 12, 2015, and PubMed, Embase, and the Cochrane Central Register of Controlled Trials for primary studies from January 1, 2013, to May 24, 2016; clinicaltrials.gov was searched on March 9, 2016.¹ Given these search criteria, the authors failed to find publications describing the results of 4 pregabalin studies registered on clinicaltrials.gov.