LibGuides: Physical Therapy Research Guide: Evaluating Evidence

Levels of Evidence

There are many evidence hierarchies available. Variations of the evidence pyramid below are some of the most widely used. These tools can help conceptualize the reasearch landscape, but beware of applying them too rigidly. Different study types are best suited to answer different types of clinical questions, and a well-designed study of a type lower on the pyramid may be more credible than a poorly-designed study of a type higher on the pyramid.

Explore the resources on this page for more information about levels of evidence and evaluating studies for validity and bias.

*Book and resource reviews

Credit: Bradley A. Long [author] and Eliza Donne [graphic designer]. 2^nd ed. Harrell Health Sciences Library. Penn State College of Medicine. (2020). Creative Commons License: https://doi.org/10.26207/gr3e-6b54

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Source: https://www.slideshare.net/AsirJohnSamuel/treadmill-training-in-children-by-dr-asir-john-samuel-pt

The PEDro Scale
The PEDro scale was developed to evaluate the internal validity of trials indexed on the PEDro database, but may be applied to intervention studies across health disciplines. A set of eleven criteria is used to create a PEDro score. Click the link to learn more and download a copy of the PEDro checklist.

Critical Appraisal Resources

Critical Appraisal Skills Programme
The Critical Appraisal Skills Programme provides a trove of tools to help you learn to evaluate scientific literature, including fillable checklists for each type of study: randomized control trials, systematic reviews, cohort studies, economic evaluations, and more.
EBP Tools from University of Oxford's Centre for Evidence-Based Medicine
Catalog of Bias
Explore the many ways a study can exhibit bias at each stage of the research lifecycle with this resource from the Catalog of Bias Collaboration which sprouted from the University of Oxford's Centre for Evidence-Based Medicine.
National Library of Medicine Tutorial on Finding & Using Health Statistics
Brush up on your statistical skills by going through the whole tutorial, or just look up definitions in the handy glossary