A Randomized Clinical Trial of Inpatient Family Intervention: VI. Mediating Variables and Outcome (original) (raw)

In a randomized clinical trial of Inpatient Family Intervention (IFI) for 169 inpatients with schizophrenia, affective disorder, and a residual group of other diagnoses, results suggested significant effects favoring IFI for patients and their families. The treatment effects were limited to females and to two diagnostic groups: chronic schizophrenia patients and the bipolar subgroup of affective disorders. Using analysis of variance and correlational analyses, we examined three variables that mediate between family treatment and outcome: 1) posthospital medication compliance, 2) posthospital psychosocial treatment compliance, and 3) patient rejection by the family. Results showed robust correlations between these variables and outcomes for all diagnostic subgroups. The pattern of associations between the mediating variables and outcome was more prominent for patients treated with IFI. These results were seen most clearly in the total sample, and for the subgroups of "all females" and "poor prehospital functioning females with schizophrenia." Finally, family achievement of the goals of the family intervention were positively associated with better patient outcome, while increased family burden at discharge was associated with shorter length of time posthospital to rehospitalization. Fam Proc 30:85-99, 1991 We have recently completed a study whose principal objective was to test the efficacy of family intervention in a hospital setting (1, 3, 5, 9). The specific study questions were: Does adding inpatient family intervention (IFI) to medication and standard hospital multimodal treatment result in increased efficacy? If so, for whom, patients or families, and for which diagnostic groups? A key related question was: How does it work? This report focuses on the last question, that is, on the process by which the outcomes were accomplished. We will identify and discuss the distinction between moderating and mediating variables. Moderating variables are those that influence whether a therapy is effective. In this study, there are two critical moderating effects: gender of patient and diagnosis. In contrast, mediating variables are those that intervene between the administration of a treatment and the ultimate outcome. These variables can help explain how a therapy works. In our manual for family treatment of patients hospitalized with diagnoses of schizophrenia, affective disorder, and the other Axis-I disorders, we specified key treatment foci for the family intervention. These foci contain hypotheses about how the family might alter or maintain certain patient behaviors, particularly through the influence of three mediating variables: 1) increasing their support for medication, 2) increasing their support for other treatment compliance, and 3) decreasing rejecting behavior toward the patient.