Clinical interpretation of computerized adaptive test-generated outcome measures in patients with knee impairments.
OBJECTIVE
To describe meaningful interpretations of functional status (FS) outcomes measures estimated using a body-part specific computerized adaptive test (CAT).


METHODS
A prospective observational cohort study.


METHODS
Outpatient physical therapy clinics (291 clinics) in 30 U.S. states.


METHODS
Sample of 21,896 patients with knee impairments receiving outpatient physical therapy.


METHODS
Not applicable.


METHODS
FS estimated using CAT administration.


RESULTS
We investigated 4 approaches to clinically meaningful interpretations of outcomes data: (1) 95% confidence interval for each score estimate, (2) percentile rank of FS scores, (3) responsiveness, and (4) functional staging. Overall, precision of a single score was estimated by FS score +/-5. Based on score distribution, percentile ranks at 25th, 50th, and 75th percentiles corresponded to intake FS scores of 33, 42, and 51 and discharge FS scores of 51, 61, and 74, respectively. Results showed that 9 or higher FS change units represented statistically and clinically important improvement. Patients were classified into 6 hierarchical levels of FS using functional staging.


CONCLUSIONS
Results suggest how CAT-generated outcomes measures can be interpreted to assist clinicians and patients during rehabilitation.
Wang
Ying-Chih
YC
Focus On Therapeutic Outcomes Inc, Knoxville, TN, USA. inga-wang@northwestern.edu
Hart
Dennis L
DL
Stratford
Paul W
PW
Mioduski
Jerome E
JE
D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D007592:Joint Diseases / Q000503:physiopathology / Q000534:rehabilitation*; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D026741:Physical Therapy Modalities; D011446:Prospective Studies; D016059:Range of Motion, Articular; D020127:Recovery of Function; D012984:Software