Classifying change with the Sickness Impact Profile for Nursing Homes (SIP-NH)

The aim of this cohort study was to evaluate the concordance of the Sickness Impact Profile for Nursing Homes (SIP-NH) and Sickness Impact Profile (SIP) in classifying change. Subjects consisted of 194 consecutive long-stay nursing home residents at one academic department of the V.A. and in 8 community proprietary nursing homes in San Antonio, Texas. They were to have more than 3 months residency; to be > or = 61 years; and to be dependent in at least 2 ADLs with an MMSE score of > or = 15. Subjects were administered a 128-item SIP and a reduced 66-item SIP-NH at baseline and 4, 8, and 12-month follow-up. At each follow-up, subjects were classified into 3 mutually exclusive change categories using a change score of > or = 5 points. Concordance of the classification of subjects by the SIP-NH and SIP was evaluated. The misclassification rate as well as its direction was also assessed. Both instruments classified a little over one-quarter of the subjects as better, over a third as being unchanged, and another third as being worse at the four-month follow-up. More subjects were classified as worse by both instruments at 8 and 12 months. All kappas ranged from 0.52 to 0.78, indicating good to excellent agreement. Overall, the SIP-NH characterized persons as changed more often than the SIP with no systematic directional bias. In conclusion, the SIP-NH was concordant with the SIP in classifying change in subjects. However, we cannot say which of the two is better for detecting change. Future research must focus on defining a change score which has clinical meaning, and evaluate responsiveness to change.