Demographic information
DISEASE
The subject group prepared the questionnaire after literature search and discussion, which included age, BMI, marital status, education level, occupation, monthly income, affected extremity, disease stage, number of axillary lymph nodes extracted, time of drainage tube removal, and operation type. The data collectors collected demographic information, DASH and FACT‐B 4.0 using a unified guidance language. In this study, the patients completed the questionnaire independently as far as possible. For those who could not fill in the form in person, the collector filled the form truthfully according to the patient's descriptions.