Caregiver burden as a predictor of depression among family and friends who provide care for persons with bipolar disorder

Reliability of the Center for Epidemiologic Studies Depression Scale, a 20-item symptom checklist, is examined using data from a sample of community respondents containing Anglos (254), Blacks (270), and Mexican Americans (181). Although the survey response rate was lower for Mexican Americans, quality of the data provided by this group was not significantly different from that for Anglos or Blacks. That is, there were no differences among these groups in terms of missing data or internal consistency reliabilty (as measured by Cronbach's alpha and Spearman-Brown split halves). Factor-analytic results also demonstrate the same general structure of responses among the three groups.

The 35-item Duke Social Support Index (DSSI) measures multiple dimensions of social support and has been used extensively in cross-sectional and longitudinal studies of aging. Epidemiological studies of chronically ill, frail elderly individuals often wish to include a measure of social support. However, most multidimensional measures (including the DSSI) are long and may exhaust the patient, especially when included in an often already congested interview schedule. The authors have developed two abbreviated versions of the DSSI (23-item and 11-item) that capture the essential components of social support related to mental health outcomes and use of health services in treating elderly individuals with nonpsychiatric medical illness.

Subthreshold depression is a highly prevalent condition and a risk factor for developing a major depressive episode. Internet-based cognitive behaviour therapy may be a promising approach for the treatment of subthreshold depression. The current study had two aims: (1) to determine whether an internet-based cognitive behaviour therapy intervention and a group cognitive behaviour therapy intervention are more effective than a waiting-list control group; and (2) to determine whether the effect of the internet-based cognitive behaviour therapy differs from the group cognitive behaviour therapy intervention. A total of 191 women and 110 men with subthreshold depression were randomized into internet-based treatment, group cognitive behaviour therapy (Lewinsohn's Coping With Depression course), or a waiting-list control condition. The main outcome measure was treatment response after 10 weeks, defined as the difference in pre- and post-treatment scores on the Beck Depression Inventory (BDI). Missing data, a major limitation of this study, were imputed using the Multiple Imputation (MI) procedure Data Augmentation. In the waiting-list control group, we found a pre- to post-improvement effect size of 0.45, which was 0.65 in the group cognitive behaviour therapy condition and 1.00 within the internet-based treatment condition. Helmert contrasts showed a significant difference between the waiting-list condition and the two treatment conditions (p=0.04) and no significant difference between both treatment conditions (p=0.62). An internet-based intervention may be at least as effective as a commonly used group cognitive behaviour therapy intervention for subthreshold depression in people over 50 years of age.