Test-Retest Reliability of the OVIS Questionnaire - An Instrument to Evaluate Oncological Care from a Patient's Point of View

Objectives: The OVIS study aims to outline and assess the health-care situation of patients with breast, prostate and skin cancer in Schleswig-Holstein. The used form contains questions regarding diagnosis, therapy, rehabilitation, postoperative health care, and quality of life and was administered approximately one year after primary therapy. The objective of this study (sub-study of the OVIS study) is the evaluation of the test-retest reliability of this questionnaire in patients with breast cancer, who were questioned during and one year after primary therapy. Methods: The study population was recruited during their ambulant chemotherapy and includes women with adjuvant and neoadjuvant treatment of their breast cancer. Patients with advanced metastasis were excluded. In total 56 patients, for whom medical records and both questionnaires were available, were included in this analysis. The test-retest reliability was measured using rates of absolute agreement and Cohen's kappa with a 95 % confidence interval. Results: Of the 73 closed questions, 41 % showed good and 52 % showed moderate test-retest reliability. Test-retest reliability was high for questions regarding important moments (e. g., notification of breast cancer diagnosis), diagnostic (e. g., mammography) or therapeutic procedures (e. g., ablation mammae). Conclusions: Although the time span between both questionings was one year, the acquired values of the test-retest reliability are consistent with those from comparable studies with shorter questioning intervals. The used questionnaire is a reliable instrument to determine the health care situation of women with breast cancer in Schleswig-Holstein.