Abstract 112: Non-response Bias in Patient Reported Outcomes Research for Breast Reconstruction: Lessons from a Multi-institutional Prospective Cohort Study

Abstract

PURPOSE: Survey-based research has emerged as a primary method of evaluating the impact and outcomes of breast reconstruction in an era of patient centered care. Despite increased utilization of patient reported outcomes measures, such as the BREAST-Q surveys, there are few studies assessing non-response among study participants. Differential non-response to surveys threatens the generalizability and validity of studies evaluating patient reported outcomes. The objectives of this study were to identify independent variables associated with non-response to surveys following breast reconstruction to aid in the design and improvement of future patient-reported outcomes research. METHODS: The Mastectomy Reconstruction Outcomes Consortium is a multi-institutional prospective cohort study involving 11 leading medical centers from the United States and Canada. Data were collected through a combination of self-reported patient surveys and medical record review. Patient reported outcomes including satisfaction with breast and with care (BREAST-Q), depression (PHQ-9), and anxiety (GAD-7) were collected preoperatively and at several intervals postoperatively. Non-response rates to BREAST-Q, PHQ-9, and GAD surveys were measured at one week, three months, one year, and two years following breast reconstruction. Complication rates between questionnaire responders and non-responders were compared at one year. Multivariable logistic regression models were designed with non-response as the dependent variable. RESULTS: Among 3,083 women included in the analytic cohort, 2,060 (66.8%) underwent implant-based, 857 (27.8%) underwent autologous, and 166 (5.4%) underwent mixed breast reconstruction. Non-response rates to BREAST-Q surveys at one week, three months, one year, and two years postoperatively were 14.5%, 21.8%, 27.8%, and 34.4% respectively. At one year following reconstruction, the rate of non-response ranged from 8.0% to 41.4% among participating centers. Patient race and ethnicity, annual household income, and education were all associated with non-response to the postoperative surveys. Patients undergoing implant-based breast reconstruction were approximately half as likely to respond to BREAST-Q surveys at one year when compared with women who underwent autologous reconstruction. Neither satisfaction with care nor incidence of clinical complications was predictive of non-response to the surveys. CONCLUSION: Although patient reported outcomes are increasingly utilized to assess and compare the impact of breast reconstruction procedures, there are few studies evaluating differential non-response rates to survey instruments among study participants. In a multi-institutional, prospective cohort study, racial and ethnic minorities, and women from lower income and education groups were less likely to respond to follow-up surveys. Additionally, women who underwent implant-based breast reconstruction were approximately half as likely to respond to BREAST-Q surveys at one year when compared with women who underwent autologous reconstruction. Researchers studying patient-reported outcomes in breast reconstruction should assess and adjust for non-response bias. Future studies are needed to design and implement effective approaches to improving response rates for patients at high risk of loss to follow-up.