Objective: To investigate the effectiveness and mechanisms of a multimodal treatment including perturbation exercise directly applied in health care. Methods: A pragmatic, matched cohort study was conducted. Participants from the intervention group had chronic or recurrent low back pain and participated in a 12-week back pain prevention program. Coaches were trained to deliver multimodal care. Controls (usual care) were matched from a multi-center RCT. Outcomes were pain, disability, isokinetic trunk strength (extension/flexion) and balance (center of pressure trace). A Bayesian, sequential analysis along 8 matching procedures and moderation/mediation analyses incorporating the biopsychological avoidance-endurance model were conducted. Median values with highest posterior density intervals (HPDI) from baseline-adjusted analyses are presented. Results: Over 12 weeks, intervention and control experienced a similar decrease in pain and disability, which led to negligible average treatment effects for pain (0.5 HPDI95% [-3.6; 4.6]) and disability (1.5 HPDI95% [-2.3; 5.4]) for the intervention. Changes in functional strength and balance showed small but favorable effects for the intervention group, in particular for trunk extension (-4.1 Nm HPDI95% [-18.2, 10.0]) and monopedal stances (standardized score: 0.49 HPDI95% [0.13, 0.79]). Depression was higher in drop-outs and decreases in pain and disability were associated with decreases in depression. Distress-endurance subgroups experienced higher baseline pain and disability and showed the highest reductions in both parameters upon completion of the intervention. Conclusion: Multimodal treatments for low back pain without tailoring are possibly less effective in the context of health care than their efficacy in RCTs suggests. Targeting distress-endurance subgroups with a multimodal treatment approach is probably an effective strategy in treatment tailoring.

The authors have declared no competing interest.

Intervention: DRKS00030389, Control: DRKS00010129

This study was conducted within the MiSpEx research network and funded by the German Federal.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study was approved by the local ethics committee of the Faculty of Sport Science of Ruhr-University Bochum (EKS V 10/2017).

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Data of the treatment group, study documents and the analysis script are available in our online repository.

https://osf.io/mbrh