How can we know what is medically true?
LEVELS OF EVIDENCE:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3124652/#!po=16.6667
DEFINITIONS
Meta analyses – examination of data from a number of independent studies of the same subject, in order to determine overall trends.
RCT – randomized controlled trial is a study in which people are allocated at random (by chance alone) to receive one of several clinical interventions. One of these interventions is the standard of comparison or control.
Cohort Study – a particular form of longitudinal study (same individuals observed over the study period) that samples a cohort (a group of people who share a defining characteristic), performing a cross-section at intervals through time.
Case–control studies are often used to identify factors that may contribute to a medical condition by comparing subjects who have that condition/disease (the “cases”) with patients who do not have the condition/disease but are otherwise similar (the “controls”).