PEDro is unique. Each clinical trial indexed on PEDro is assessed for methodological quality by at least two independent PEDro-trained Raters. This month, we highlight the invaluable contribution of Raters to PEDro.

For 25 years, PEDro Raters have been critical in helping PEDro users rapidly access the best available evidence by using the PEDro Scale to rate the quality of trials. PEDro Raters have rated 98% of all clinical trials indexed in PEDro, representing a total of over 128,700 ratings. This is a remarkable collaborative feat! The PEDro Partnership is grateful for the important contributions of the volunteer PEDro Raters.

What’s stayed the same?

PEDro Scale
The PEDro Scale was developed in 1999 and has remained unchanged. The PEDro Scale evaluates the methodological quality of a randomised clinical trial by the presence or absence of items related to risk of bias, overall article quality, and helps PEDro users to choose a quality article before reading it. The PEDro Scale is a valid and reliable tool. The inter-Rater agreement is high, indicating that results can be reproduced (Interclass Coefficient = 0.91).

As of August 2024, 98% of clinical trials (46,406 articles) indexed on PEDro had been rated. You can learn more about the PEDro Scale in this Research Note (Moseley AM, Pinheiro MB. Research Note: Evaluating risk of bias in randomised controlled trials. Journal of Physiotherapy 2022;68(2): 148-150. DOI:10.1016/j.jphys.2022.02.003).

Trained Raters to rate trials on PEDro
Originally, trials indexed in PEDro were rated by experienced researchers. Over time, the PEDro Scale Training program was developed for potential PEDro Raters with a must-pass assessment. This ensures the reliability and accuracy of trials rated on PEDro. The course is now self-paced, hosted online and it can be undertaken by anyone interested in using and understanding the PEDro scale. Find out more about the PEDro Scale training program here.

At least two independent Raters for each trial
PEDro scores are accurate and reliable. There is high agreement between Raters (ICC=0.91) and good agreement for individual items (Kappa = 0.52 to 1.00; N.C. Foley, et al. Phys Ther, 86 (2006), pp. 817-824). To ensure accuracy, each trial is assessed by at least two independent PEDro Raters. Any disagreements between their ratings are resolved by a third experienced Rater who finalises the PEDro score.

What’s changed for PEDro Raters?

Performing the ratings
PEDro Raters have used different platforms over the past 25 years to rate articles. Originally, Raters were mailed paper articles to rate. Later, articles were sent by email before a web-platform was developed. In 2023, the web-platform was upgraded with user input to provide Raters with new features and an improved experience.

Opportunities to network globally
An online community of PEDro Raters was created in response to PEDro Raters interest in connecting with other likeminded supporters of evidence-based physiotherapy. In 2023, the private PEDro Raters Facebook group was launched, and now more than 75% of current Raters are members.

This online community provides real-time opportunities such as discussing articles and ratings, collaborating and expanding Raters’ knowledge about evidence-based practice.

Languages represented by PEDro Raters
PEDro Raters span over many countries and speak a diverse range of languages including Arabic, Bosnian, Chinese, Croatian, Czech, Danish, Dutch, English, Filipino, French, German, Hindi, Italian, Japanese, Korean, Malay, Norwegian, Polish, Portuguese, Russian, Serbian, Spanish, Slovak, Swedish, Tamil, Turkish and Ukrainian.

Here is a world map showing the countries with at least one language represented by the network of PEDro Raters.

PEDro indexes articles in any language and are only assessed by Raters with the appropriate language skills. PEDro is always on the look-out for potential Raters with language skills other than English to contribute to PEDro ratings, particularly Persian, Greek, Danish, Slovak, Czech, Turkish, German. If you would like to help rate trials on PEDro, complete the PEDro Scale Training Program!