This is the second of two articles on the conceptual and methodological
problems involved in comparing the effectiveness of drugs and psychotherapy
in the treatment of mental disorders. Part II focuses on differences
between psychotherapy and pharmacotherapy in the nature of treatment
effects and related goals for treatment, differences in the time course of
treatment effects, and potential sources of bias in the research setting.
In designing comparative studies of psychotherapy and pharmacotherapy,
investigators should address methodological choices explicitly and consider
the implications for interpretation of findings.