Background: Documentation of concurrent and late side effects of medical interventions to prevent and treat breast cancer is important in research and clinical practice. We used the Breast Cancer Prevention Trial (BCPT) Symptom Checklist to develop an instrument (BCPT Symptom Scales) that could be used to assess side effects and to examine correlates of the derived symptom dimensions among patient populations.
Methods: Exploratory and confirmatory factor analyses were conducted using data from the 42-item BCPT Symptom Checklist completed by four distinct patient populations (N = 2208) who had previously been diagnosed with breast cancer or were at risk for the disease. We examined associations among the resulting BCPT Symptom Scales and demographic and cancer-related variables and a widely used measure of health-related quality of life.
Results: Exploratory and confirmatory factor analyses revealed eight factors corresponding to physical symptoms associated with cancer treatment, chemoprevention, menopause, and normal aging: hot flashes, nausea, bladder control, vaginal problems, musculoskeletal pain, cognitive problems, weight problems, and arm problems. On the derived BCPT Symptom Scales, women reported somewhat higher mean scores on scales for hot flashes, pain, and weight problems than on scales for the other symptoms. Demographic and cancer-related variables accounted for up to 15% of the interindividual variance in how women responded to the symptom scales. The most consistent predictors of reporting greater symptoms included lower education level and previous receipt of chemotherapy.
Conclusions: Meaningful symptom dimensions, identified across four samples of women, were associated with demographic and breast cancer-related variables. The BCPT Symptom Scales offer a valuable refinement of the original BCPT Symptom Checklist to assess side effects associated with the treatment and prevention of breast cancer.