We compared the metric properties of the University of California, Los Angeles (UCLA) activity scale, the Tegner score, and the Activity Rating Scale for assessment of activity levels in 105 patients undergoing THA (48 women; mean age, 63.4 years) and 100 patients undergoing TKA (61 women; mean age, 66.5 years). We assessed construct validity by correlating these scales with the International Physical Activity Questionnaire and different traditional patient self-reporting outcome measures. Test-retest reliability, feasibility, and floor and ceiling effects also were determined. The UCLA scale showed the strongest correlations with the other measures (r = -0.35 to 0.56 for THA; r = -0.55 to 0.23 for TKA) and was the only scale that discriminated between insufficiently and sufficiently active patients undergoing THA and TKA. The UCLA scale had the best reliability, provided the highest completion rate, and showed no floor effects. It seems to be the most appropriate scale for assessment of physical activity levels in patients undergoing total joint arthroplasty.
Level of evidence: Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.