title: Reliability in Measuring Preinjury Physical Function in Orthopaedic Trauma.
abstract: OBJECTIVE
  In orthopaedic trauma, patients' functional status scores cannot be collected before injury. Due to the lack of these data, it is difficult to reliably determine if patients have returned to their preinjury level of physical function. The goal of this article is to determine if patients' assessment of preinjury function agrees with that of familiar proxies, to determine whether patient assessment of preinjury function may be regarded as reliable.
  
  
  METHODS
  At first postinjury outpatient follow up, orthopaedic trauma patients and their proxies were asked to independently complete the PROMIS physical function computer adaptive test (PF CAT) based on how they perceived the function of the patient before injury. Intraclass correlation, paired sample t tests, and 95% confidence intervals were used to analyze patient-proxy agreement.
  
  
  RESULTS
  Fifty patient-proxy pairs completed the questionnaire at an average of 14.3 (SD = 1.1) days postoperative (average 19.3, SD = 12.1 days postinjury). Patient mean PF CAT score was 57.92 (SD = 10.38) for patients and 56.59 (SD = 11.50) for proxies. Paired samples t test showed that patient's PF CAT scores were not significantly different from proxy scores [mean score difference = 1.33; 95% CI = (-1.28, 3.94); P = 0.311]. Intraclass correlation between patient and proxy scores was 0.79. There was no notable bias.
  
  
  CONCLUSIONS
  Good agreement in PF CAT preinjury assessment between patients and proxies support patients' ability to report reliable preinjury physical functioning in the early postinjury setting using the PF CAT.
authors.affiliation: *Department of Orthopaedic Surgery, University of Utah, Salt Lake City, UT; and †Department of Biomedical Informatics, University of Utah, Salt Lake City, UT.
authors.forename: Ami R
authors.initials: AR
authors.lastname: Stuart
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Higgins
authors.forename: Man
authors.initials: M
authors.lastname: Hung
authors.forename: Charlene R
authors.initials: CR
authors.lastname: Weir
authors.forename: Erik N
authors.initials: EN
authors.lastname: Kubiak
authors.forename: David L
authors.initials: DL
authors.lastname: Rothberg
authors.forename: Charles L
authors.initials: CL
authors.lastname: Saltzman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D059026:Diagnostic Self Evaluation; D005260:Female; D050723:Fractures, Bone / Q000175:diagnosis* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D063868:Patient Outcome Assessment; D010809:Physical Fitness; D019727:Proxy; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires; D015599:Trauma Severity Indices; D016896:Treatment Outcome; D055815:Young Adult