Page 35 - The value of total hip and knee arthroplasties for patients

DISCUSSION
The current study demonstrated that nearly 60% of patients undergoingTHA orTKA 2 completed a set of PROMs preoperatively, in addition each time the questionnaire
was assessed more than 80% of the invited patients returned the questionnaire.
After 2 years of follow-up the response rate was respectively 79% and 78% forTHA
and TKA patients.
As compared to other registers, our inclusion rates were lower than the inclusion rates in the SHAR (86% for a set of PROMs consisting of the EQ-5D, Pain (VAS) and Satisfaction (VAS)), the NZJR (69% and collected the EQ-5D and the OHS/ OKS) and NRJ (75%, collected the EQ-5D, OHS/OKS and satisfaction). Conversely, our postoperative participation rates were comparable as reported by the SHAR (90% after 6 months) and somewhat higher than reported in the NRJ (75-76% after 6 months and 64% after 1 year).12;13
A possible explanation for the higher inclusion rates of the SHAR is that our questionnaire was more extensive which possibly influenced the response rate. Another explanation for the different inclusion rates could be that patients in some of the aforementioned studies such as the SHAR27 completed the preoperative questionnaires at the outpatient clinic, whereas in our study preoperative questionnaires were sent to patients’ home addresses. This was done as we anticipated that anxiety might be present at the day of hospital admission. However, in retrospect, not using a personal approach may have led to a relatively large proportion of patients not completing the preoperative forms. A last possible explanation is that we did not contact the patients who did not respond to the invitation . Our aim was to create and investigate a non-invasive structure which would be easy to implement. Nevertheless, inclusion-rates would probably have been higher if we contacted all patients who did not respond to the preoperative questionnaire by telephone.
The hypothesis that response rates of questionnaires sent by regular mail are lower as compared to response rates of questionnaires completed at the outpatient clinic is supported by a comparison of our results with previous studies.8 The aforementioned studies sent the follow-up questionnaires by regular mail as well, resulting in response rates similar to ours.In our study,solely patients who were willing
feasibility of collecting multiple PROMs
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