LibGuides: Occupational Therapy Research Guide: Evaluating Evidence

Levels of Evidence

Level I – Systematic Reviews, Meta-Analyses, Randomized Control Trials

Level II – Two groups, non-randomized studies ( e.g., cohort, case control, pre/post-test)

Level III – One group, nonrandomized studies (e.g., before and after, pre/post-test, time series, longitudinal studies)

Level IV – Descriptive studies that include analysis of outcomes (single subject design, case series, case study, survey studies)

Level V – Expert opinion, literature reviews, research not performed on human subjects

Hissong, A.N., Lape, J. E., & Bailey, D. M. (2015). Bailey’s research for the health professional. (3rd ed.). Philadelphia, PA FA Davis.

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
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.
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