Adapting PROMIS Physical Function Items for Users of Assistive Technology

The Patient Reported Outcomes Measurement Information System (PROMIS) is an NIH roadmap initiative to develop and test banks of items measuring patient reported outcomes for public use. This goal of this study was to adapt items from the PROMIS physical function (PF) domain bank so that they are appropriate and relevant to individuals who use wheelchairs, mobility aids, and other assistive technology (AT). Items were reviewed by experts and those determined not appropriate or relevant to AT users were removed or adapted when possible. Additional items were created to fill gaps in the domain. Cognitive interviews with users of AT (N=31) were completed such that each new or adapted item was reviewed by at least eight individuals with varying AT needs. Based on these results a candidate item bank was developed and administered to 400 individuals with multiple sclerosis and spinal cord injury. A subset of unchanged domain items was also administered to allow for calibration along the same metric as the original PF item bank. Preliminary data analyses suggest that the Chronbach alpha for the new items was 0.986. Several items had low information and required response categories be collapsed for analysis. Comparisons of test information functions for new and original items indicate that the new AT adapted items extend the PROMIS PF domain at the lower end of the scale, as was expected. After additional analysis adapted items will be included in the publically available PF item bank, extending its usability in populations with varying AT needs.