A Pilot Study to Modify the SF-36V Physical Functioning Scale for Use With Veterans With Spinal Cord Injury
Presented to the VA Health Services Research and Development Service Annual Research Conference, 2005, Baltimore, MD, and the American Paraplegia Society, 2005, Las Vegas, NV.
Abstract
Luther SL, Kromrey J, Powell-Cope G, Rosenberg D, Nelson A, Ahmed S, Quigley P. A pilot study to modify the SF-36V physical functioning scale for use with veterans with spinal cord injury.
Objective
To develop a valid and reliable spinal cord injury (SCI) specific physical functioning (PF) scale for the Veterans Health Administration (VHA) version of the 36-Item Short-Form Health Survey.
Design
A mixed qualitative and quantitative research design was used. In phase 1, a pool of SCI-specific PF items was generated based on focus groups with patients and health care providers. In phase 2, the psychometric properties of the SCI-specific PF scale were established.
Setting
A VHA SCI center.
Participants
The sample consisted of valid responses from 359 veterans with traumatic SCI who were seen at a VHA SCI center during the prior year (2002).
Interventions
Not applicable.
Main Outcome Measure
Physical functioning in people with SCI.
Results
Exploratory factor analysis was conducted separately on respondents with lower neurologic-level injuries (paraplegia, 53% [n=190]) and those with higher neurologic-level injuries (tetraplegia, 45% [n=163]) and identified 9 items loading on 1 factor in both groups. These 9 items were included in separate item response theory (IRT) model analyses for each subgroup. Based on the IRT analysis, 1 item was eliminated, resulting in an 8-item, SCI-specific PF scale.
Conclusions
Although several of the items in the SCI-specific PF scale showed floor effects, particularly in people with tetraplegia, we found excellent reliability and strong support of convergent and divergent validity of the scale.
aVISN 8 Patient Safety Research Center, James A. Haley Veterans Hospital, Tampa, FL
bCollege of Public Health, University of South Florida, Tampa, FL
cCollege of Education, University of South Florida, Tampa, FL
dCollege of Nursing, University of South Florida, Tampa, FL.
Reprint requests to Stephen L. Luther, PhD, Patient Safety Center, 11605 N Nebraska Ave, Tampa, FL 33612-5738
Supported by the Department of Veterans Affairs, Veterans Health Administration VISN 8, VISN 8 Patient Safety Research Center, and VISN 8 Measurement and Evaluation Team.
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated.
ABSTRACT