Source: SUNY Downstate/Medical Research Library of Brooklyn, http://library.downstate.edu/EBM2/2100.htm
The highest levels of the pyramid contain studies with the greatest credibility such as systematic reviews and meta-analyses. Studies at the lower levels of the evidence pyramid (randomized controlled trials and case reports) are more plentiful considered less reliable than those at higher levels. In searching databases, it might be helpful to use a search strategy that include terms such as systematic reviews, meta-analyses, or literature reviews.
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