In an effort to keep sharpening my critical appraisal skills, I am going to start a research review series where I choose one article to summarize and discuss in each blog post. In each post, I will summarize the study’s methods and results, discuss its strengths/limitations, and talk about how it may affect my practice. Please feel free to share your thoughts in the comments below as well. To start this series off, the article I have selected is:
Michaleff ZA, Maher CG, Lin C-WC, Rebbeck T, Jull G, Latimer J, et al. Comprehensive physiotherapy exercise programme or advice for chronic whiplash (PROMISE): a pragmatic randomised controlled trial. Lancet (London, England). 2014 Jul 12;384(9938):133–41.
Purpose: to determine if a 12-week comprehensive PT exercise program is more effective than 1 advice session and telephone support for people with chronic whiplash. They also investigated potential treatment effect modifiers.
Patients between the ages of 18-65 with chronic grade 1 or 2 whiplash (>=3 months and <5 years) who feel at least moderate pain or moderate activity limitation due to pain, and are not currently receiving treatment (excluding drugs). n = 172 (86 in each group)
Both groups received a booklet entitled “Whiplash injury recovery: a self-management guide” that had information about WAD, advice on managing symptoms, and some simple neck exercises.
Comprehensive exercise program group: received up to 20 individually tailored and supervised exercise sessions lasting 1 hour each, spread out over 12 weeks (2x/week for 8 weeks, then 1x/week for 4 weeks). Weeks 1-4 consisted of “Motor Relearning” exercises including craniocervical flexion training, neck extensor training, scapular training, posture re-education, and sensorimotor exercises. Weeks 4-6 was a transition period where focus was shifted from c-spine specific motor-relearning exercises to a graded activity program based on the patients’ identified functional goals (via the Patient Specific Functional Scale). Weeks 7-12 consisted of this individually-designed graded activity program. A submaximal, progressive aerobic exercise program was also prescribed throughout the entire 12 weeks as per ACSM guidelines. Manual therapy could only be done in the first week if the PTs decided it was necessary. They were also given a 12-week HEP to be done on the days where they did not receive treatment. Cognitive behavioural therapy strategies were encouraged throughout (e.g. skill acquisition by modelling, setting progressive goals, self-monitoring via diaries). Principles of pacing were also incorporated once the transition had been fully made to a graded activity program.
Advice group: received a 30-minute in-person consult with a PT, which consisted of reading the booklet, practicing the exercises with as little assistance as needed from the PT, and clarifying any questions/concerns with the PT. They were also encouraged to practice the exercises independently at their discretion and to follow the advice given in the booklet. They were given the opportunity to contact the PT up to two times via telephone if they had any more questions/concerns.
All outcome measures were taken at baseline, 14 weeks, 6 months, and 12 months after randomization
Primary: average pain intensity over the previous week using the numerical pain rating scale (NPRS)
Potential treatment effect modifiers that were investigated:
Primary outcome: A 12 week comprehensive PT exercise programme did not provide additional benefit over advice for reducing average pain intensity over the preceding week at any of the time points.
Secondary outcomes: A 12 week comprehensive PT exercise programme provided significant, though not clinically worthwhile, benefit over advice on self-reported recovery (all time points) and functional ability (at 14 weeks only). There was no difference between groups for the other secondary outcomes.
Treatment effect modifiers: None of the measures were found to significantly affect treatment effectiveness
Compliance: in the comprehensive exercise group, median # of sessions attended was 17 (IQR 13-20). In the advice group, the median number of advice sessions and phone follow-up sessions was 1 (IQR 1-3).
Follow-up: ranged between 83-96% for both groups at each time point
No serious adverse events were reported.
- PTs were well trained to ensure the interventions were delivered consistently and appropriately: they had experience delivering these treatments prior to the trial, they were trained at a 1 day workshop prior to the start of the trial, they had a 2nd training session halfway through the trial to ensure interventions were given as per trial protocol, each PT had one treatment and one advice session audited by experts in the field
- Post-hoc sensitivity analysis was done to assess effect of missing data
- Interpretation of results considered not just statistical significance but also clinical significance
- Prospectively registered trial that followed a pre-specificed protocol
- The researchers did a mini systematic review & meta-analysis, finding 3 other high quality RCTs (PEDro 7-8/10) that addressed a similar question —> results of this meta-analysis suggested that an exercise programme doesn’t provide clinically meaningful benefit over advice as measured by disability outcomes in the short term (additional benefit was -3.3 [95% CI -5.5 to -1.1] on a 0-100 scale)
- Results consistent with recent similar RCT involving participants with acute WAD
- Note: PEDro score of 8/10 so a fairly high quality study (lost points for blinding of therapists & participants, which would not have been possible anyway for these types of interventions)
- Were the two interventions equally effective or equally ineffective? I would have liked to see if there was a clinically significant difference at each time point compared to baseline for both groups. It didn’t look like there would have been based on the results presented but it would have been nice to see that analysis. I’m not sure that I have the data I would need to calculate this from their results. If neither interventions were actually effective, what can therapists be doing better?
- It seems like the exercise principles taught to the patient in weeks 1-4 (Motor relearning phase) conflicts with the exercise principles taught in weeks 7-12 (Graded activity – particularly pacing). In the treatment protocol found in the Appendix, under the Guide to Motor Relearning Program section, it says that “a fundamental rule is that the exercises must not produce pain, especially in those participants with evidence of augmented central pain processing” (not my bold). The educational booklet also reinforces this. Later in the Appendix, under the Cognitive Behavioural Principles section, it promotes time-contingent progression of activity rather than pain-contingent to reduce focus on pain. It even says “It is important that education and reassurance is given as factual and specific as possible and vague or anxiety-inducing responses such as ‘let pain be your guide’ are avoided.” I wonder how these mixed messages affect the effectiveness of either styles of treatment and the patients’ understanding of pain. I didn’t see anything that directly addressed these changes in attitude towards pain in the Appendix.
- Those of you who know me know that the notion of a “good” posture is a pet peeve of mine. See this blog post by Greg Lehman to understand why. “Good” posture is promoted in both the booklet and in the comprehensive exercise program. How does this affect a patient’s views of their body and more importantly, their pain, disability, and self-efficacy? (I can only hypothesize here – I don’t know of any research on this but that would be an interesting qualitative study!)
- It was interesting that none of the treatment effect modifiers they measured were significant, especially catastrophising, which is something I have been taught to look out for when assessing patients. I recall listening to a Pain Science and Sensibility Podcast where they discussed a study that found that people who scored high in catastrophising did not respond to graded exposure treatment for non-specific spinal pain whereas those who scored low and mid did respond. I wonder what the difference was here. One thing I would want to know is how much variability was there with these potential treatment effect modifiers that they measured. If there is not enough variability, then would it be more difficult to detect a treatment effect modifier? (i.e. if everyone is clustered around the same level on the PCS, then “high” catastrophizers would actually be close on the scale to “low” catastrophizers)
- How adherent were the participants to their home exercises? The study mentioned exercise diaries but I didn’t read anything on how they quantified adherence to home exercises and how it compared between groups
Implications for Practice
One thing this study tells me is that more is not necessarily better. I think it calls into question whether or not we should be asking patients to come in 1-2x/week for 12 weeks of treatment when it doesn’t seem to provide more benefit than 1-3 advice sessions (2 of which can even be on the phone!). I’m sure private practice owners don’t like the sound of that but that’s great for public health! Knowing the results of this study, and since I will be in a private practice setting (I don’t know what work will be like but from what I’ve experienced on placement and what I’ve heard from others it seems like there is pressure/expectations for people to come in more frequently), I think I would want to be honest with my patient and tell them, “You are probably going to do just as well if you come in 1-2x/week for 12 weeks or 2-3 more times over the next 12 weeks spread out as you see fit. What research has found is that more is not always better. That being said, if you feel more comfortable coming more frequently in the beginning (e.g. 1x/week for 2-3 weeks) and then tapering it off from there, I would be happy to go with that as well. It’s your choice. What would you prefer?”
Part of me wants to protect my profession and protest, “but physio still works!! forget the research, humans are too complex to research” and another part says “well, it’s what the research says, physio is no use”. Then I realize that’s a false dichotomy. Instead of ignoring this study (among others) and sticking with doing what we always do with patients who have neck pain, and instead of declaring that going to see a physio is a waste of time, perhaps we need to continue looking for things we can do as physios that make a clinically meaningful difference.
Please feel free to share your thoughts below or shoot me an email :).