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Evidence-Based Practice (SCGH): Study Type

Select the Best Studies to Answer Your Question

For a focused search apply filters for the study type, starting from the highest level of evidence and moving along the hierarchy from left to right.

Note: the highest level of evidence currently available for your question may be further down the hierarchy, especially in new and emerging areas of practice.

More on the hierarchy of evidence

Question Type

Therapy Interventions - symptoms, function, morbidity, mortality, costs.
Diagnosis Power of a test to differentiate between those with or without a disease condition
Prognosis Establishing the likely course over time due to factors other than interventions
Prevention Identify & modify risk factors/early diagnosis through screening
Harm Effects of harmful agents (exposure) including therapies

David L. Sackett. Evidence-based medicine: how to practice & teach EBM. Churchill Livingstone, 2000, p.19.


A well constructed, answerable and focused question:

Does riding a bicycle reduce tremor in patients with Parkinson's Disease?

Patient or problem Parkinson's Disease
Intervention Bicycling
Comparison nil OR standard treatment
Outcome Reduce Tremor
Question Type Therapy
Study Type Randomised Controlled Trial or Cohort Study

Having identified the type of question and the best study design to answer that question you are now ready to Search

Study Type

Question Type  Study Design
Therapy Randomised controlled trial > cohort studies
Diagnosis Prospective blind comparison to gold standard > cross sectional
Prognosis Cohort Studies > case control studies > case series
Prevention Randomised controlled trial > cohort studies
Harm Cohort studies > case control studies > case series