Outcome profiles in the treatment of unipolar depression

Treatment efficacy is typically evaluated by examining group means and pre-post change scores. Although informative, such analyses may obscure individual or subgroup differences in response (outcome profiles). The present study used two different methods to define treatment outcome profiles--rationally-derived criteria (Frank et al., Archives of General Psychiatry 48, 851-855, 1991) and dynamic clustering--to evaluate four treatments of unipolar depression: behaviour therapy, amitriptyline, psychodynamic psychotherapy and relaxation training (attention placebo). The profiling methods yielded similar results. Regardless of treatment, the majority of patients displayed either a recovery or nonremission outcome profile, with relatively few instances of remission followed by a recurrence of depression. These findings challenge the view that any of the treatments are associated with a strong tendency to relapse, at least over the 3-month follow-up period. To further characterize the major outcome profiles, discriminant analysis was performed. Results indicated that recovery and nonremission profiles differed in that the latter was associated with a longer and more severe index episode and greater neuroticism. A number of variables, including family history of depression and therapists' prediction of outcome, failed to distinguish recovered from unremitted patients.