Background: Psychiatric surveys conducted in prison populations find high prevalence rates, but diagnoses may be difficult in this particular context. None of these surveys have been conducted in France.
Methods: 800 incarcerated male were sampled at random. Each prisoner was interviewed by a group of 2 clinicians, at least one of them being a senior psychiatrist. One of the clinicians used a structured clinical interview which generated DSM IV diagnosis (MINI plus); the second completed the procedure with an open clinical interview.
Results: Prevalence rates for a diagnosis given independently by both clinicians and for a consensual diagnosis were respectively: 3.8% (6.2%) for schizophrenia, 17.9% (24%) for major depressive disorder, 12.0% (17.7%) for generalized anxiety and 10.8% (14.6%) for drug dependence.
Conclusion: Psychiatric diagnosis can be difficult to interpret in prison, especially using traditional standardized interviews. The approach proposed here, with good reliability and closer to a day-to-day clinical practice, yields high prevalence rates.