Staying up to date as a physical therapist is a challenge because the research underpinning the science and practice of our profession is growing exponentially.1 The growth is well illustrated by the history of randomized controlled trials (RCT). In 1929, there was only 1 RCT evaluating a physical therapy treatment; by 1972, there were 100; by 1986, 1,000; by 2005, 10,000; and today, there are more than 12,000 RCTs. As a consequence, a “mid-career” physical therapist (who graduated in 1980) now has access to 25 times more RCTs compared with when they graduated. Even with the advent of physical therapy–specific databases such as Hooked on Evidence and PEDro, it has become impossible to keep up to date by reading primary research papers: the job has just gotten too big.
An efficient way for physical therapists to keep up to date is to read recent systematic reviews. For people with little spare time, systematic reviews are a godsend because they can distill the evidence from dozens of primary studies. Although systematic reviews on the effectiveness of interventions2 are probably the most common, there also are reviews that focus on cost-effectiveness,3 the views of patients,4 prognosis,5 diagnosis,6 clinical prediction rules,7 psychometric properties of scales8 or measures,9,10 cross-cultural adaptation of self-report measures,11 definitions of epidemiological terms,12 and practice guidelines.13 Most questions that arise in physical therapist practice lend themselves to evaluation within a systematic review.
Well-conducted systematic reviews identify, appraise, and summarize research in an unbiased fashion and so provide reliable information to guide clinical decision making. Unfortunately, though, not all systematic reviews are well conducted.14 And that is where the PRISMA statement comes in. The PRISMA statement provides a checklist of items for reporting systematic reviews and meta-analyses. When this key information is reported in a review, readers are in a much better position to judge the strength and weaknesses of a review and, most importantly, to judge whether the information provided is relevant to the specific clinical question they want to answer.
About PRISMA
The Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) statement evolved from the earlier QUOROM (Quality of Reporting of Meta-analyses) statement. QUOROM was a reporting checklist for meta-analyses of RCTs; however, as noted earlier, not all systematic reviews take this form. Beyond the expanded scope, other important differences with PRISMA are items for the review protocol and registration, for the specific electronic search strategy, and for describing sources of funding. More information on PRISMA is contained in the reprinted article in this issue15 and also at the PRISMA Web site (http://www.prisma-statement.org).
Reports of systematic reviews that attend to the PRISMA statement will provide readers with the key information they need in order to judge the value of a systematic review. It is for this reason that PTJ joins with other journals such as BMJ, Annals of Internal Medicine, PLoS Medicine, and Journal of Clinical Epidemiology in endorsing PRISMA. We will ask our authors to follow this statement when preparing manuscripts reporting a systematic review.
Those of you who have recently viewed our instructions for authors will know that PTJ has endorsed a range of reporting checklists analogous to PRISMA. PTJ asks authors to attend to the STARD statement when they report a diagnostic study, the STROBE statement when they report an observational study, and the CONSORT statement when they report an RCT. There are a number of extensions to the CONSORT statement that focus on the additional information required for reports of cluster trials and non-inferiority and equivalence trials and for trials evaluating herbal medicines or nonpharmacological interventions.
Why Read a Checklist?
Checklists like PRISMA are obviously of value to physical therapists who are preparing a manuscript; however, they do have other uses. For researchers, they provide an excellent reminder of the sorts of issues to consider when submitting a grant application to an agency such as the Foundation for Physical Therapy or National Institutes of Health. They also are useful for our reviewers and others who critically appraise research reports because the checklists specify the salient issues that need to be considered. However, reporting checklists are not designed to assess the quality of a published study. There are separate scales to assess the risk of bias (methodological quality) of a study. Examples include the QUADAS scale for diagnostic studies16 and the PEDro scale for RCTs.17,18
At the end of the day, the primary purpose of PTJ is to improve patient care. PTJ has adopted the PRISMA statement to help us better communicate our content to the physical therapists who provide that care.
- American Physical Therapy Association