OBJECTIVES: (1)Assess patients’ quality of life before and after total primary knee replacement using EQ-5D-3L profiles. (2)Demonstrate the information gained from disaggregated Patient Reported Outcome Measures instead of utility or other summary scores.

METHODS: Patient and clinical outcomes data from two multicentre studies were re-analysed, focusing on descriptions of patients’ quality of life using the EQ-5D-3L. 1,879 patients were included from 4 countries(USA, UK, Australia, New Zealand) operated on by the same surgeons using two different knee replacement systems. Descriptive analyses included levels (no, some, severe problems) within EQ-5D dimensions (Mobility, Self-Care, Usual Activities, Pain & Discomfort, Anxiety & Depression) and profiles (combinations of dimensions and levels) at baseline and 3 follow-up points, including changes over time and differences between implants and countries. Regression analysis quantified the relationship between the EQ-5D-3L components and the EQ VAS.

RESULTS: Problems with Mobility, Usual Activities and Pain & Discomfort, in that order, were most frequent for pre-operative patients. There were large improvements in every dimension after surgery, but the time that this was observed differed: for Mobility, Self-Care and Anxiety & Depression, most of the improvement occurred during the first year; for Usual Activities and Pain & Discomfort, over two years. Additionally, 56% of patients reported no problems with pain & discomfort, 70% with usual activities and 79% with mobility. Analysing profiles, 85% of patients experienced an unequivocal improvement, 5.9% had no change, 3.5% worsened and 5.6% a mixed change at two years follow-up. Anxiety & Depression had the greatest impact on EQ VAS scores; while Mobility and Usual Activities were also important; Usual Activities was particularly important post-surgery.

CONCLUSIONS: The methods revealed insights that PROMs summary scores obscure, including how conditions and treatments impact on different aspects of patients’ quality of life and their relative importance to self-assessed quality of life overall.