Most accurate results is obtained from which clinical study (AIIMS Nov 11)
|A||Double blinded RCT|
|B||Systematic review (methanolysis)|
|D||Case control study|
The best study or the research design which gives us the most accurate results is the randomized controlled trial.
It must be remembered that metanalysis is not a study design but only a method of analyzing the data of smaller studies which may yield non significant results. So we may have to do a metanalysis of such similar small comparable studies so that the effective sample size increases thereby increasing the power & level of significance of the study & may even make a statistically non significant result statistically significant.
But if the question is based on Preference of Studies for establishing causation:
c. Cohort study
d. Case control study
e. Cross sectional studies
f. Ecological studies