Agreement among clinical assessment scales for knee replacement surgery

The ‘performance variability’ of 15 different assessment systems after knee replacement was analyzed. The systems were applied to both knees of 52 patients who had received compartmental knee replacement. The ratings were standardized, compared, and demonstrated a wide variation of the outcomes. The results contradicted the opinion that the outcome differences between knee evaluation systems are small. The notion that different knee evaluation systems measure different underlying factors was supported. More detailed operative specifications for the different systems were suggested as a first step to decrease the variability among assessment systems.