Validation and application of the breast cancer distress thermometer in Chinese patients: Cutoff scores and stage-specific manifestations.

Objective: The first aim was to update and revise the Distress Thermometer (DT) to enhance its applicability in breast cancer patients. The second aim was to define the cutoff scores of the Breast Cancer Distress Thermometer (DT-BC) and identify the prevalence and manifestations of distress across different stages of the disease. Methods: The DT-BC was updated according to the Distress Management Guidelines from NCCN, Version 3.2019, and revised through a literature review, expert consultation, and patient surveys. Reliability was assessed using reliability analysis, test-retest reliability, and Kappa value; validity was tested via content and criterion-related validity. The cutoff scores of DT-BC were determined using the Hospital Anxiety and Depression Scale and receiver operating characteristic (ROC) curve analysis. Sensitivity and specificity were calculated based on the area under the curve (AUC). Nonparametric tests and logistic regression were used to analyze distress manifestations. Results: The total Cronbach's α for the problem list was 0.805, and the test-retest reliability coefficient was 0.750, with a Kappa value of 0.458. The content validity index was 1.00, and the criterion-related validity coefficient was 0.476. The DT-BC cutoff score was 6 for the diagnostic and postoperative treatment stages, 5 for the neoadjuvant and postoperative stages, and 4 for the rehabilitation stage. The prevalence and manifestations of distress varied significantly across different stages, with emotional distress being a common manifestation throughout the disease process. Conclusions: Based on the results of this psychometric evaluation, the DT-BC is considered suitable for use in the routine psychological screening of breast cancer patients.