A Cochrane review included 8 studies. No significant difference in effect was found between marital therapy and individual psychotherapy, either for the continuous outcome of depressive symptoms: SMD –0.12 (95% CI –0.56 to 0.32, 6 studies), or the dichotomous outcome of proportion of subjects remaining at caseness level: RR 0.84 (95% CI 0.32 to 2.22, 3 studies). In comparison with drug therapy, a lower drop-out rate was found for marital therapy: RR 0.31 (95% CI 0.15 to 0.61), but this result was greatly influenced by a single study. The comparison with no/minimal treatment, favoured marital therapy for depressive symptoms, SMD –1.28 (95% CI –1.85 to –0.72, 2 studies) and showed a smaller effect for persistence of depression (1 study).
Comment: The quality of evidence is downgraded by inconsistency (variability in results across studies) and by imprecise results (limited study size for each comparison).