Time to Deterioration in Quality of Life Score as a Modality of Longitudinal Analysis in Patients with Breast Cancer

Abstract Purpose. This prospective multicenter study explored different definitions of time to deterioration (TTD) in quality of life (QoL) scores, according to different cutoffs of the minimal clinically important difference (MCID) as a modality for longitudinal QoL assessment in breast cancer patients. Methods. QoL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 and BR-23 before surgery, after surgery, and 6 and 12 months later. The global health score, arm symptoms score (BRAS), and breast symptoms score were analyzed. For a given baseline score, QoL was considered to have deteriorated if this score decreased by ≥5 point…