A Computerized Adaptive Test for Patients With Hip Impairments Produced Valid and Responsive Measures of Function

Hip CAT functional status score distributions at admission (FS Intake) and discharge (FS Discharge). NOTE. Intake data from the 8714 patients with intake FS estimates and discharge data from the 3841 patients with discharge data.

Test information functions. NOTE. Test information function curves were estimated by using item parameter estimates from the original data (n=444 sample 2).²⁶ Abbreviations: Top 7 IER (Low Function Patients), test information function using the 7 most commonly used items in the hip CAT for patients with lower FS scores; Top 7 IER (High Function Patients), test information function using the 7 most commonly used items in the hip CAT for patients with higher FS scores; Full Test (P&P Version), test information function using all items in the hip CAT item bank for all patients; Top 7 IER (Entire Sample), test information function using the 7 most commonly used items in the hip CAT for all patients regardless of FS scores. Abbreviation: IER, item exposure rate.

The measure precision of CAT-estimated FS abilities. Abbreviation: SEM, standard error of the mean.

The hip CAT functional status measure SE 95% CI upper limits and percent of patients per FS range at intake (N=8714).

The hip CAT FS measure MDC 90% and 95% CI upper limits and percent of patients per FS range at intake (n=3838).