The statistical analysis of matched data in psychiatric research.

Clinical studies in psychiatry frequently involve the analysis of matched pairs, in which each patient is matched with his or her psychiatric clinician. If the response variable of interest is dichotomous, then McNemar's chi 2 test for correlated proportions may be applied to the resulting data. However, this test assumes that the set of matched pairs are statistically independent, an assumption that is violated if some clinicians are matched with more than one patient. In this article we present alternatives to McNemar's test for dealing with this problem.