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Physical Therapy 710

Studies Defined

The following brief definitions follow the evidence pyramid:

Systematic Review: a comprehensive survey of a topic that takes great care to find all relevant studies of the highest level of evidence, assess each study, synthesize the findings from individual studies in an unbiased, explicit and reproducible way and present an impartial summary of the findings with due consideration of any flaws in the evidence. 

Meta-Analysis: a systematic, objective way to combine data from many studies, usually from randomized controlled clinical trials, and arrive at a pooled estimate of treatment effectiveness and statistical significance.

Randomized Controlled Trial: a study in which subjects are randomly assigned to one of two groups: the experimental group receive the intervention that is being tested, and the control group receive either no treatment (placebo) or standard treatment. RCTs are considered the “gold standard” in medical research, best for answering questions about the effectiveness of different therapies or interventions.

Cohort Study: Identifies participants who currently have a certain condition or receive a treatment and are followed over time & compared with another group of people who are not affected by the condition.

Case Control Study: participants who already have a certain condition are compared with people who do not. 

Case Report/Case Series: reports on the treatment of individual patients with the same condition, or on a single patient.


PICO Clinical Questions: the Cochrane Clinical Answers provide concise, evidence-based answers to PICO clinical questions based on Cochrane Reviews. They are designed to be actionable and to inform point-of-care decision-making. Study a few to become good at asking PICO questions.