A protocol has been developed for a novel systematic literature review that is intended to help expand the understanding about how healthcare researchers design strength-based exercise interventions and set dose parameters for testing in randomized controlled trials (RCTs). The review, published in BMJ Open, presents a novel approach to investigate the dose prescriptions used for exercise interventions evaluated in RCTs, using trials in rheumatoid arthritis (RA) as an example.
When healthcare investigators design strength-based exercise interventions, they must select an appropriate dose to be tested prior to assessing its effect using a definitive, phase 3 RCT. Compared with early-phase testing used in pharmaceuticals trials, it is debatable whether exercise-based trials use the same rigor when determining tolerated dosage. Thus, it is not clear whether participants in such trials are initially prescribed optimal doses of exercise, which may, in turn, affect study outcomes.
Using trials of strength-based exercise interventions in adults with RA as an example, the investigators sought to identify the proportion of published RCTs that use phase 1 or phase 2 trials with dose escalation methodology to establish prescription parameters. They also sought to determine the type and level of evidence used to underpin prescription parameters of strength-based exercise interventions assessed by RCTs, explore the applicability and consistency of the evidence supporting prescription parameters in RCTs, and examine whether a relationship exists between the risk for bias in RCTs that assess strength-based exercise interventions and the level of evidence used to underpin prescription parameters.
The researchers concentrated on RCTs intended to evaluate strength-based exercise interventions in adults with RA (men and women ≥18 years) that were published after 2000. For each RCT selected, they identified the evidence used to support prescription parameters. Both the trial identified and the underpinning evidence will have key information available on the intervention using the template for intervention description and replication checklist.
A major limitation of the current review is that the investigators needed to rely on the description of interventions provided by the respective authors, so the findings are dependent on the quality of the reporting.
The researchers concluded that the use of a narrative approach to evaluate the extracted data is exploratory in nature. Given the probable mixed and unpredictable nature of the evidence reviewed, however, this type of approach is the most appropriate.
Boniface G, Norris M, Williamson E, Gandhi V, Kirtley S, O’Connell N. What evidence is used to underpin the design of strength-based exercise interventions evaluated in randomised controlled trials for rheumatoid arthritis? A systematic review protocol. BMJ Open. 2018;8(9):e024127.