The MCID for TKR is around 15 on WOMAC, while with the SF-36 of at least 10 points. These values should not be considered as absolute thresholds.

The Spanish version of the HADS demonstrated good reliability and validity when used in medical patients.

These results suggest a direct relationship between explicit appropriateness criteria and better health-related quality-of-life outcomes after THR and TKR surgery. Our results support the use of these criteria for clinical guidelines or evaluation purposes.

These values indicate expected gains after THR. However, the MCID and MDC values must be viewed cautiously due to the uncertainty of these estimators and should not be considered as absolute thresholds.

The previous parameters tested showed acceptable results for an evaluation tool. These results support the use of this algorithm as an aid in formulating clinical practice guidelines and to promote the appropriateness of TKR.