Assessing mobility in children using a computer adaptive testing version of the pediatric evaluation of disability inventory

Arch Phys Med Rehabil. 2005 May;86(5):932-9. doi: 10.1016/j.apmr.2004.10.032.


Objective: To assess score agreement, validity, precision, and response burden of a prototype computerized adaptive testing (CAT) version of the Mobility Functional Skills Scale (Mob-CAT) of the Pediatric Evaluation of Disability Inventory (PEDI) as compared with the full 59-item version (Mob-59).

Design: Computer simulation analysis of cross-sectional and longitudinal retrospective data; and cross-sectional prospective study.

Setting: Pediatric rehabilitation hospital, including inpatient acute rehabilitation, day school program, outpatient clinics, community-based day care, preschool, and children's homes.

Participants: Four hundred sixty-nine children with disabilities and 412 children with no disabilities (analytic sample); 41 children without disabilities and 39 with disabilities (cross-validation sample).

Interventions: Not applicable.

Main outcome measures: Summary scores from a prototype Mob-CAT application and versions using 15-, 10-, and 5-item stopping rules; scores from the Mob-59; and number of items and time (in seconds) to administer assessments.

Results: Mob-CAT scores from both computer simulations (intraclass correlation coefficient [ICC] range, .94-.99) and field administrations (ICC=.98) were in high agreement with scores from the Mob-59. Using computer simulations of retrospective data, discriminant validity, and sensitivity to change of the Mob-CAT closely approximated that of the Mob-59, especially when using the 15- and 10-item stopping rule versions of the Mob-CAT. The Mob-CAT used no more than 15% of the items for any single administration, and required 20% of the time needed to administer the Mob-59.

Conclusions: Comparable score estimates for the PEDI mobility scale can be obtained from CAT administrations, with losses in validity and precision for shorter forms, but with a considerable reduction in administration time.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Child
  • Child, Preschool
  • Computer Simulation*
  • Cross-Sectional Studies
  • Disability Evaluation*
  • Disabled Children / rehabilitation*
  • Female
  • Humans
  • Infant
  • Male
  • Outcome Assessment, Health Care / methods*
  • Rehabilitation / standards*
  • Rehabilitation Centers
  • Sensitivity and Specificity