Assessing the quality of research outputs in physiotherapy
Assessing the quality of research outputs is a challenging issue. Systematic reviews and meta-analyses of randomized trials have a pivotal role informing clinical practice and policy decisions and there is a broad agreement that the methodological quality of primary studies should be carefully assessed (1).The Physiotherapy Evidence Database (PEDro) scale is one of the most frequently used scales aimed to assess the methodological quality of clinical trials in the field of physiotherapy (1, 2).The reported reliability ICC values ranged from 0.55 (95% confidence interval CI: 0.47- 0.65) for the original scale, to 0.82 (95% CI: 0.70 – 0.89) for the Portuguese version of the Scale (3, 4). The PEDro scale consists of 11 items encompassing external validity (item 1), internal validity (items 2 to 9), and statistical reporting (items 10 to 11): 1. Eligibility criteria and source 2. Random allocation 3. Concealed allocation 4. Baseline comparability 5. Blinding of participants 6. Blinding of therapists 7. Blinding of assessors 8. Adequate follow-up (>85%) 9. Intention-to-treat analysis 10. Between-group statistical comparisons 11. Reporting of point measures and measures of variability (5). Each item is scored as either present (1) or absent (0), leading to a maximum score up to 10 (4). A trial is considered of moderate to high quality if it scores at least 6/10 (4). The purpose of the PEDro score is to help researchers identify trials that have good internal validity (items 2-9) and that report enough data to make their results interpretable (items 10-11) (5, 6). Applying, and interpreting items correctly are critical to a high-quality evidence-based health practice. But, the Cochrane Collaboration distinguishes between the methodological quality of a study and the risk of bias: A study of high quality can still be at high risk of bias (7). The Cochrane risk of bias (RoB) tool focuses on the internal validity of trials (7). RoB includes the assessment of six domains of bias: selection bias, performance bias, detection bias, attrition bias, reporting bias, and other bias (7). So, it is important to assess the impact of study quality and the risk of bias on trial results in physiotherapy. The PEDro scale has been shown to be a reliable tool in physiotherapy to assess methodological quality and can be used to distinguish between high-quality and low-quality clinical trials together with RoB (4,5,7). This open access tools provide dissemination, transparency and availability of research output. Also, in open access the PEDro scale and RoB facilitates research development in physiotherapy and encourage interdisciplinary research.
Manuela Filipec
University North
Department for Physiotherapy
Varaždin, Croatia
ORCID ID: 0000-0002-3845-0336Anica Kuzmić
University North
Department for Physiotherapy
Varaždin, Croatia
ORCID ID: 0000-0001-7620-1851Nikolina Zaplatić Degač
University North
Department for Physiotherapy
Varaždin, Croatia
ORCID ID: 0000-0001-5534-9742