Therapeutic quality of exercise interventions for chronic low back pain: a meta-research study using i-CONTENT tool

OBJECTIVE: To assess the therapeutic quality of exercise interventions delivered in chronic low back pain (cLBP) trials using the international Consensus on Therapeutic Exercise aNd Training (i-CONTENT) tool and its inter-rater agreement.

METHODS: We performed a meta-research study, starting from the trials' arms included in the published Cochrane review (2021) 'Exercise therapy for chronic low back pain'. Two pairs of independent reviewers applied the i-CONTENT tool, a standardised tool designed to ensure the quality of exercise therapy intervention, in a random sample of 100 different exercise arms. We assessed the inter-rater agreement of each category calculating the specific agreement. A percentage of 70% was considered satisfactory.

RESULTS: We included 100 arms from 68 randomised controlled trials published between 1991 and 2019. The most assessed exercise types were core strengthening (n=27 arms) and motor control (n=13 arms). Among alternative approaches, yoga (n=11) and Pilates (n=7) were the most representative. Overall, most exercise interventions were rated as having a low risk of ineffectiveness for patient selection (100%), exercise type (92%), outcome type and timing (89%) and qualified supervisor (84%). Conversely, some items showed more uncertainty: the safety of exercise programmes was rated as 'probably low risk' in 58% of cases, exercise dosage in 34% and adherence to exercise in 44%. The items related to exercise dosage (31%) and adherence (29%) had heterogenous judgements, scoring as high risk of ineffectiveness or probably not done. Among all exercise types, Pilates scored best in all domains. A satisfactory specific agreement for 'low risk category' was achieved in all items, except dosage of exercise (60%) and adherence to exercise (54%).

CONCLUSION: Exercises delivered for patients with cLBP generally demonstrate favourable therapeutic quality, although some exercise modalities may present poor therapeutic quality related to dosage and adherence. While the i-CONTENT judgements generally showed satisfactory specific agreement between raters, disagreements arose in evaluating some crucial items.