Predicting self-care with patients and family members' affective states and family functioning.

People with cancer manage the side effects of treatment with the assistance of their family members. This study was designed to describe self-care behaviors (SCBs) initiated by patients and their family members and to determine the relationship between patients and family members' affective states and family functioning and SCBs. Using a longitudinal design, 42 patients and 40 family members were followed during 3 cycles of chemotherapy (12-16 weeks). The patients completed measures of affective state (POMS) each cycle; patients and family members completed a family functioning measure (F-COPES) at second cycle only; and the patients reported in an SCB log on an ongoing basis. The overall pattern of SCBs corroborated previous findings. The average number of SCBs initiated was 1.4 per side effect. Depression and vigor significantly predicted SCBs at Cycle 1 only. The severity of side effects consistently predicted SCB over the 3 cycles (r 2 = -0.39 to -0.46). Patients who experienced more severe side effects were at risk of diminished self-care.