The SIP68: a measure of health-related functional status in rehabilitation medicine

Abstract

Objective: To demonstrate the usefulness of the SIP68, a recently developed short version of the sickness impact profile (SIP), for measuring health-related functional status in rehabilitation medicine.

Design: Survey, oral interviews.

Setting: Patient's homes.

Patients: 315 persons (out of 423 that could be reached) with a spinal cord injury whose mean average age was 39.4 years and who were living in the community at the time of the interview.

Main outcome measures: Internal consistency is tested by computing Cronbach's alpha. Construct validity is tested by principal components analysis and computing Cattell's similarity index. Criterion validity is tested by comparing SIP68 results with the level of the spinal cord lesion and with results of specific measures of disability (Barthel Index) and life satisfaction (Life Satisfaction Questionnaire), and with vocational status.

Results: SIP68 scores and subscale scores indicate that our spinal cord injured group falls well within the scope of this instrument. Internal consistency figures are good and the proposed six-dimensional structure is confirmed. Criterion validity figures are also satisfactory. Barthel Index scores show high agreement with the scores of the subscale "somatic autonomy," moderate agreement with the other physically related and socially related subscales, and low agreement with the mentally related subscales of the SIP68. LSQ scores show low agreement with the physically related subscales and moderate agreement with the mentally and socially related subscales. Figures of vocational status show strongest agreement with the socially oriented subscales.

Conclusion: The SIP68 is recommended as a useful generic outcome measure for research in rehabilitation medicine.