Validation of the Spinal Cord Injury-Functional Index for Use in Community-Dwelling Individuals With SCI.

OBJECTIVE

To evaluate the psychometric properties of the Spinal Cord Injury-Functional Index (SCI-FI) instruments in a community-dwelling sample.

DESIGN

Cross-sectional study.

SETTING

Community setting.

PARTICIPANTS

Individuals (N=269) recruited from 6 SCI Model Systems sites.

INTERVENTIONS: Not applicable.

MAIN OUTCOME MEASURES: Participants completed computer adaptive test and short form versions of 4 SCI-FI/Capacity (C) banks (ie, Ambulation, Basic Mobility, Fine Motor, Self-Care) and 1 SCI-FI/Assistive Technology (AT) bank (Wheelchair Mobility) at baseline and after 2 weeks. The Self-Report Functional Measure (SRFM) and the clinician-rated motor FIM were used to evaluate evidence of convergent validity.

RESULTS

Pearson correlations, intraclass correlation coefficients, minimal detectable change, and Bland-Altman plots supported the test-retest reliability of the SCI-FI instruments. Correlations were large with the SRFM (.69-.89) and moderate-to-large for the FIM instrument (.44-.64), supporting convergent validity. Known-groups validity was demonstrated by a significant main effect of injury level on all instruments and a main effect of injury completeness on the SCI-FI/C instruments. A ceiling effect was detected for individuals with incomplete paraplegia on the Fine Motor/C and Self-Care/C Short Forms.

CONCLUSION

Findings support the test-retest reliability, convergent validity, and known-groups validity of the SCI-FI/C instruments and the SCI-FI/AT Wheelchair Mobility instruments for use by community-dwelling individuals.