Poster Presentation 51st International Society for the Study of the Lumbar Spine Annual Meeting 2025

Convergent validity and responsiveness of the Impact PROMIS, 9-item PROMIS questionnaire, in individuals with chronic non-specific low back pain (LBP). (#122)

Zahra ZE Ebrahimi 1 , Luciana LM Macedo 1 , Tara TP Packham 1 , Ayse AK Kuspinar 1
  1. McMaster, Hamilton, ON, Canada
  1. Background, objective and design: The (National Institute of Health (NIH)  has recommended using a 9-item PROMIS, named Impact PROMIS in low back pain (LBP) (Deyo, Dworkin et al. 2015). There are insufficient studies assessing its psychometric properties. Therefore, this study aims to evaluate the convergent validity, responsiveness and MCID of the Impact PROMIS. This is a secondary analysis of an RCT (Macedo, Hodges et al. 2021).
  2. Method

2.1 Convergent Validity: was assessed with the Disability (ODI), Quality of Life (EQ-5D-5L), Pain (NRS), and Function (PSFS) using correlation analyses. Moreover, we conducted relevant analyses for each sub-scale. We set a-priori hypotheses for the correlation analysis (Table 1), and then we conducted hypothesis testing.

2.2 Responsiveness: we used 3 approaches: 1) distribution-based with effect sizes (ES) and a t-test; 2) construct with correlations and hypothesis testing; 3) criterion with ROC curves. We set the cut-off for the AUC at 0.7.

67070d041e879-Convergent+validity+and+responsiveness+of+the+Impact+PROMIS+-+Word+2024-10-09+7_10_50+PM.png

2.3 MCID: we used the criterion approach to determine the MCID. We opted for a point where both sensitivity and specificity are maximized.

2.4 Sample size: To estimate sample size, we used Fisher's z test, so we required to include 161 participants.

  1. Result: We included data of 220 participants, of whom 142 (64.5%) were women with mean age of 50.3 years (±14.9). Ceiling or floor effects were not present.

3.1. Convergent Validity: Correlation between Impact PROMIS and ODI=0.78, NRS=0.77; PSFS -0.56, EQ-5D-5L VAS=-0.62, index=-0.75. The one-tailed analysis demonstrated that identified correlations were significantly higher than a-priori hypotheses for NRS, ODI and EQ-5D-5L but not for PSFS. We met 4 out of 5 hypotheses for total score and 3 out of 4 for subscale analyses.

3.2 Responsiveness: Effect size was calculated large, and t-test showed a statistically significant improvement at follow-up. For construct approach, the correlation was conducted and one-tailed analysis showed that we met 3 out of 5 hypotheses. Lastly, ROC curves showed an AUC of 0.76 (95% CI: 0.69 to 0.82) (Figure 1).

67070d041e879-Convergent+validity+and+responsiveness+of+the+Impact+PROMIS+-+Word+2024-10-09+7_10_37+PM.png

3.3 MCID was estimated 7 points with a sensitivity of 0.61 and specificity of 0.8.

Fig. 1 Receiver operating characteristic curves for the Impact PROMIS questionnaire for ‘improved’ and ‘unchanged’ on the GPE. Impact PROMIS change scores (area under curve = 0.76). Abbreviations: GPE, Global Perceived Effect of change. The highlighted point is the OCP

4. Conclusion: Impact PROMIS showed high convergent validity and acceptable responsiveness in individuals with chronic non-specific LBP, providing further support the use of the Impact PROMIS. However, we strongly recommend using a legacy outcome measure for function

  1. Deyo, R. A., S. F. Dworkin, D. Amtmann, G. Andersson, D. Borenstein, E. Carragee, J. Carrino, R. Chou, K. Cook and A. DeLitto (2015). "Report of the NIH Task Force on research standards for chronic low back pain." Physical therapy 95(2): e1-e18.
  2. Macedo, L. G., P. W. Hodges, G. Bostick, M. Hancock, M. Laberge, S. Hanna, G. Spadoni, A. Gross and J. Schneider (2021). "Which Exercise for Low Back Pain?(WELBack) trial predicting response to exercise treatments for patients with low back pain: a validation randomised controlled trial protocol." BMJ open 11(1): e042792.