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Biomechanical Changes Related to Low Back Pain: An Innovative Tool for Movement Pattern Assessment and Treatment Evaluation in Rehabilitation
Published on: December 13, 2024
Responsiveness of the numeric pain rating scale in patients with low back pain
John D Childs1, Sara R Piva, Julie M Fritz
1Department of Physical Therapy, Wilford Hall Medical Center, San Antonio, TX, USA. childsjd@bigfoot.com
Study Design:
Cohort study of patients with low back pain (LBP) receiving physical therapy.
Objective:
To examine the responsiveness characteristics of the numerical pain rating scale (NPRS) in patients with LBP using a variety of methods.
Summary Of Background Data:
Although several studies have assessed the reliability and validity of the NPRS, few studies have characterized its responsiveness in patients with LBP.
Methods:
Determination of change on the NPRS during 1 and 4 weeks was examined by calculating mean change, standardized effect size, Guyatt Responsiveness Index, area under a receiver operating characteristic curve, minimum clinically important difference, and minimum detectable change. Change in the NPRS from baseline to the 1 and 4-week follow-up was compared to the average of the patient and therapist's perceived improvement using the 15-point Global Rating of Change scale.
Results:
The majority of patients had clinically meaningful improvement after both 1 and 4 weeks of rehabilitation. The standard error of measure was equal to 1.02, corresponding to a minimum detectable change of 2 points. The area under the curve at the 1 and 4-week follow-up was 0.72 (0.62, 0.81) and 0.92 (0.86, 0.97), respectively. The minimum clinically important difference at the 1 and 4-week follow-up corresponded to a change of 2.2 and 1.5 points, respectively.
Conclusions:
Clinicians can be confident that a 2-point change on the NPRS represents clinically meaningful change that exceeds the bounds of measurement error.
