For a study, the researchers aimed to assess construct validity through hypothesis testing and the examining reliability and discrimination of the PROMIS-29 v2.0 by the use of item response theory (IRT) analyses. Patient-Reported Outcomes Measurement Information System (PROMIS) 29.0 version 2.0 includes 28 questions for the 7 domains of Physical function, Anxiety, Depression, Fatigue, Sleep disturbance, Social role, and Pain interference, and one item related to pain intensity. They used the Quality Outcomes Dataset lumbar registry, evaluation of the construct validity of the PROMIS-29 v2.0 against pain intensity measures for back and leg, the Oswestry Disability Index, the EQ5D 3L-visual analog scale (quality of life), and proxy measures of activities, mobility, and self-care was done. IRT was also used to test PROMIS-29 v2.0 assumptions and fit. The sample had 652 surgery patients (mean age=60.1, SD=14.0) who were suffering from high levels of baseline disability. Hypothesis testing confirmed the direction and magnitude of the correlation between the PROMIS and legacy measures in 10 of the 12 hypotheses. IRT diagnosed 3 misfit items but otherwise adequate scale reliability and unidimensionality. The PROMIS-29 v2.0 measured several different constructs pertinent to a patient’s health and recovery during spine surgery. The researchers enhanced the importance that the PROMIS-29 v2.0 tool was a useful and effective outcome measure for populations who receive spine surgery.
