Perspective of potential patients on the hospital volume-outcome relationship and the minimum volume threshold for total knee arthroplasty: a qualitative focus group and interview study.

Background: Total knee arthroplasty (TKA) is performed to treat end-stage knee osteoarthritis. In Germany, a minimum volume threshold of 50 TKAs/hospital/year was implemented to ensure outcome quality. This study, embedded within a systematic review, aimed to investigate the perspectives of potential TKA patients on the hospital volume-outcome relationship for TKA (higher volumes associated with better outcomes).

Methods: A convenience sample of adults with knee problems and heterogeneous demographic characteristics participated in the study. Qualitative data were collected during a focus group prior to the systematic review (n = 5) and during telephone interviews, in which preliminary results of the systematic review were discussed (n = 16). The data were synthesised using content analysis.

Results: All participants (n = 21) believed that a hospital volume-outcome relationship exists for TKA while recognising that patient behaviour or the surgeon could also influence outcomes. All participants would be willing to travel longer for better outcomes. Most interviewees would choose a hospital for TKA depending on reputation, recommendations, and service quality. However, some would also choose a hospital based on the results of the systematic review that showed slightly lower mortality/revision rates at higher-volume hospitals. Half of the interviewees supported raising the minimum volume threshold even if this were to increase travel time to receive TKA.

Conclusions: Potential patients believe that a hospital volume-outcome relationship exists for TKA. Hospital preference is based mainly on subjective factors, although some potential patients would consider scientific evidence when making their choice. Policy makers and physicians should consider the patient perspectives when deciding on minimum volume thresholds or recommending hospitals for TKA, respectively.