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abstractpubmed· Abstract 2017 November-December,· item PMID:29055914
Evidence-Based Medicine and the Problem of Healthy Volunteers. Healthy controls are subjects without the disease being studied but may have other conditions indirectly affecting outcome. In the present epidemics of obesity a few subjects with undiagnosed nonalcoholic fatty liver disease enter clinical studies as controls, producing biased results. Stricter selection criteria should be considered to prevent this risk.