Measuring health status of people who are wheelchair-dependent: validity of the Sickness Impact Profile 68 and the Nottingham Health Profile.

Abstract

Several questionnaires measuring health status are available, but their validity and correspondence between them in people with severe physical disabilities is not well known. In this study, the equivalence of the Nottingham Health Profile (NHP) and the Sickness Impact Profile 68 (SIP68) was examined. Patients were 111 people who were wheelchair-bound due to spinal cord injuries (45%), rheumatic diseases (27%) or other causes (28%). Internal consistency, associations between scales of both questionnaires and with criterion variables (reflecting upper and lower extremity function, perceived health, social functioning and well-being) were examined. Both the NHP and the SIP68 were of acceptable clinimetric quality (Cronbach's alpha 0.53-0.85). Agreement between scales of both questionnaires was moderate for scales reflecting emotional health (0.56) and for scales reflecting physical (0.22-0.68) and social functioning (0.28-0.35). The NHP reflects perceived health, whereas the SIP68 reflects functional health status. In rehabilitation research, a careful choice between available health status measures must be made.