Four Variables Were Sufficient for Low Back Pain: Determining Which Patient-Reported Tools Pain and Disability Improvements.

Abstract

<b>OBJECTIVE:</b> To predict 30- and 180-day improvements in disability and pain for patients seeking physical therapy care for low back pain (LBP). <b>DESIGN:</b> Longitudinal cohort. <b>METHODS:</b> Baseline assessment was completed by 259 patients with chief complaint of LBP, and the assessment includes psychosocial measures (Keele STarT Back Screening [SBST] and the Optimal Screening for Prediction of Referral and Outcome Yellow Flag [OSPRO-YF] tools), the Optimal Screening for Prediction of Referral and Outcome Review of Symptoms (OSPRO-ROS) and the Review of Symptoms Plus (OSPRO-ROS+) tools, the Charlson Comorbidity Index (CCI), the Area Deprivation Index (ADI), and the National Institute of Health Chronic Pain Criteria (NIH-CP). Using the Modified Low Back Disability Questionnaire (MDQ) and the Numeric Pain Rating Scale (NPRS) as primary outcomes, statistical analysis determined multiple sets of predictor variables with similar model performance. <b>RESULTS:</b> The parsimonious "best model" for prediction of the 180-day MDQ change included 3 predictors (Admit MDQ, NIH-CP, and OSPRO ROS+) because it had the lowest penalized goodness-of-fit statistic (BIC = -35.21) and the highest explained variance (R2 = 0.295). The parsimonious "best model" for 180-day NPRS change included 2 variables (Admit NPRS and OSPRO-ROS+) with the lowest penalized goodness-of-fit statistic (BIC = -18.2) and the highest explained variance (R2 = 0.190). <b>CONCLUSION:</b> There were many model options with similar statistical performance when using established measures to predict MDQ and NPRS outcomes. A potential variable set for a standard predictive model that balances statistical performance with pragmatic considerations included the OSPRO-ROS+, OSPRO-YF, NIH-CP definition, and admit MDQ and NPRS scores. <i>J Orthop Sports Phys Ther 2022;52(10):685-693. Epub: 12 August 2022. doi:10.2519/jospt.2022.11018</i>.