Regularly reported patient surveys are an important dimension of hospital quality management. This study investigates whether providing hospital staff with interim feedback on patient survey results following a best practices workshop can help hospitals improve patient centeredness. Standardized surveys with consecutive patient samples were administered in accredited breast cancer center (BCC) hospitals in one German state (18 million inhabitants), over a 6-month period, in 2012. Two studies were conducted by applying a combination of regression point displacement (RPD) and interrupted time series (ITS) designs. In Study 1, 2 of the 27 hospitals that had previously participated in a best practices workshop to discuss patient-centeredness issues were randomly chosen and were provided interim feedback of patient survey results and workshop minutes. In Study 2, 4 randomly chosen hospitals of 32 that had not participated in the workshop also received interim feedback but no workshop minutes. Control hospitals in both studies neither received feedback nor workshop minutes. The impact of interim feedback was evaluated by applying graphical assessments and multiple regression analyses. Both graphical assessments (locally weighted scatterplot smoothing (LOESS) lines, RPD plots) suggested an effect of interim feedback. Multiple regression results did not unambiguously support these findings. The suggested design approach may prove particularly useful to assess effects in pilot studies, when resources are not available to conduct a randomized study or when its conduct is contingent on initial, positive evidence.