Epidemiologic methods for psychiatry

Meet the paper

In 2004 the WHO World Mental Health Survey Consortium published face-to-face interviews with 60,463 adults across 14 countries. Twelve-month prevalence of any disorder ranged from 4.3% in Shanghai to 26.4% in the United States — a six-fold spread, using the same instrument, in the same three years.^[15]

So which is it: is Shanghai six times healthier, or is something in the method doing the work? That single question is the whole of this topic. Case definition, instrument version, severity threshold, recall window, response rate, cultural idiom of distress, and stigma-driven refusal all move a prevalence estimate — before any biology gets a vote.^[1][15]

And the same surveys carry the number that funds services. Between 35.5% and 50.3% of serious cases in developed countries, and 76.3% to 85.4% in less-developed countries, received no treatment in the preceding 12 months. That is a treatment-gap argument built entirely on getting the denominator right.^[15]

Etymology for viva gold: epidemiology is Greek epi plus demos plus logos — "the study of what is upon the people". The unit of analysis is baked into the word: it was never about one patient.^[1]

References16ShowHide

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