Well designed head to head randomised controlled trials are generally considered to provide the most rigorous research evidence on the relative effects of interventions. 1 Evidence from such trials is often limited or unavailable, however, and indirect comparison may be necessary.
An august committee had for the first time relied only on the most rigorous scientific evidence to formulate guidelines to prevent heart attacks and strokes, which kill one out of every three Americans.
A few years ago, the National Sleep Foundation NSFF) convened a panel of experts in sleep, physiology, internal medicine, neurology and psychiatry, among other specialties, to conduct a thorough review of all relevant medical research and to develop age-specific recommendations for appropriate sleep duration based on the most rigorous scientific evidence available.
Yet we meant to do it this way because randomized controlled trials are considered to provide the most methodologically rigorous evidence.
Conditional cash transfer programmes (CCTs) in Latin America and Asia, which make cash benefits conditional on household members' participation in education, health and nutrition services, are reviewed here because most strong, rigorous evidence to date on cash transfer impacts come from these programmes.
In an attempt to clarify the comparative effect of prolonged versus intermittent infusion β-lactam antibiotics on mortality, clinical cure, and adverse effects, we analyzed RCTs that offered the most methodologically rigorous evidence from the available studies.
The third, and most rigorous level of evidence, is a randomized, controlled clinical trial.
The most rigorous sources of evidence included in this review were also the leanest on contextual and mechanism data.
These reviews are the most rigorous summary of the evidence available.
