Predictive validity and responsiveness of the functional ambulation category in hemiparetic patients after stroke

Arch Phys Med Rehabil. 2007 Oct;88(10):1314-9. doi: 10.1016/j.apmr.2007.06.764.


Objective: To determine the reliability, concurrent and predictive validity, and responsiveness of the Functional Ambulation Category (FAC) in hemiparetic patients after stroke.

Design: Prospective cohort.

Setting: An early rehabilitation center for patients with neurologic disorders.

Participants: Fifty-five nonambulatory patients after first-ever stroke, with duration of illness between 30 and 60 days, were included.

Interventions: Not applicable.

Main outcome measures: FAC, Rivermead Mobility Index (RMI), walking velocity, step length, and six-minute walking test (6MWT) were assessed at the beginning, after 2 and 4 weeks of rehabilitation, and again 6 months later. After 6 months, community ambulation was also assessed. Test-retest and interrater reliability, concurrent, discriminant, and predictive validity and responsiveness of the FAC were calculated.

Results: Based on video examinations, high test-retest reliability (Cohen kappa=.950) and interrater reliability (kappa=.905) were found. FAC scores at the beginning and after 2 weeks, 3 weeks, and 6 months correlated highly with the RMI (Spearman rho=.686, rho=.787, rho=.825, rho=.893, respectively), distance walked in the 6MWT (rho=.949, rho=.937, rho=.931, rho=.906, respectively), walking velocity (rho=.952, rho=.939, rho=.902, rho=.901, respectively), and step length (rho=.952, rho=.932, rho=.896, rho=.877, respectively) at the same time points (all P<.001). The RMI, walking velocity, step length, and distance walked in the 6MWT differed for each FAC category (P<.001). After 4 weeks of rehabilitation, an FAC score of 4 or higher predicted community ambulation at 6 months with 100% sensitivity and 78% specificity. FAC scores changed significantly between the first 2 and second 2 weeks (Wilcoxon z=8.7, z=7.9, respectively; both P<.001) of the inpatient rehabilitation program.

Conclusions: The FAC has excellent reliability, good concurrent and predictive validity, and good responsiveness in patients with hemiparesis after stroke.

MeSH terms

  • Female
  • Gait*
  • Humans
  • Male
  • Middle Aged
  • Observer Variation
  • Outcome Assessment, Health Care / methods*
  • Paresis / etiology
  • Paresis / physiopathology
  • Paresis / rehabilitation*
  • Predictive Value of Tests
  • Prospective Studies
  • Rehabilitation Centers
  • Severity of Illness Index
  • Stroke / complications
  • Stroke / physiopathology
  • Stroke Rehabilitation*
  • Walking*