Abstract
Objectives:
Patient-Reported Outcomes Measurements Information System (PROMIS) computer adaptive testing (CAT) has been shown to be a valid and reliable means to assess patient-reported outcomes and is increasingly utilized within orthopedic research and clinical care. All PROMIS domain scores are standardized to a population mean of 50 with 10 points representing one standard deviation. Normal scores and distributions for a subset of a healthy young athletic population have not been established and may be different from the general population where PROMIS was validated. The purpose of this study is 1) to establish normative PROMIS domain scores for Physical Function, Mobility, Upper Extremity, and Pain Interference and 2) to determine if differences exist by sex or age.
Methods:
Healthy collegiate athletes (18 to 23 years of age) were prospectively enrolled to complete a battery of PROMIS CAT domains including Mobility (v2.0), Upper Extremity Function (v2.0), Pain Interference (v1.1), and Physical Function (v2.0). Athletes were excluded if currently affected by an injury. In addition, the athletes provided information regarding their age, gender, primary sport, and secondary sport(s). Mean scores (± standard deviation), distribution of data, as well as identify any ceiling or floor effects were calculated. Ceiling and floor effects were assessed by the percentage of participants with the highest or lowest possible score on a domain. A significant ceiling or floor effect was present when greater than 15% met this criteria.
Results:
A total of 194 healthy athletes were included in the study, including 118 (60.8%) males and 76 (39.2%) females. Mean PROMIS scores as follows: Mobility: 58.2 ± 4.1, Upper Extremity Function: 57.4 ± 5.8, Pain Interference: 43.2 ± 6.2, and Physical Function: 62.9 ± 6.7. Distributions of scores for Mobility and Upper Extremity observed strong ceiling effects by 77.3% and 66% of subjects respectively scoring the maximal score (Figure 1). Similarly, 63.9% of subjects exhibited a floor effect for Pain Interference. However, Physical Function scores were not found to be affected by ceiling nor floor effects (8.8%). The Physical Function domain differed most from expected population-based mean (50) with the mean being more than one standard deviation above (62.9). Sex and age showed no statistically significant differences in any of the PROMIS domain scores.
Conclusion:
While PROMIS domains have been shown to be valid and reliable in quantitatively evaluating the baseline and subsequent rehabilitation of the average adult, differences in healthy athletic populations are important to understand. PROMIS domains of Mobility, Upper Extremity Function and Pain Interference demonstrate significant ceiling and floor effects in more than 2/3 of healthy athletes. The Physical Function domain did not demonstrate floor and ceiling effects but did demonstrate the largest difference between the healthy athletic population and the general population mean.
Distribution of PROMIS domains in healthy athletes (bars) compared to established distributions in the general adult population (normal curve) for (A) Physical Function, (B) Mobility, (C) Upper Extremity Function, and (D) Pain Interference. Population means are shown by the black vertical line (50) and healthy athletes mean scores are shown as a red vertical line for each domain.