Momenter ved tolkning av vitenskapelige artikler

English summary Issues of interpretation of scientific articles Nor Tannlegeforen Tid. 2024; 134: 932-7. Knowledge of study designs is important in order to evaluate critically the relevance and credibility of scientific articles. Such knowledge enables the reader to ask critical questions regarding the evidence base of research outcomes. The quality of this evidence may be arranged in a so-called evidence pyramid, which indicates that results from study designs near the top of the pyramid have higher evidence than those lower down. Systematic Reviews and Meta-analyses, if based solely on Randomised Controlled Trials (RCT), are considered to have the highest-ranking evidence base. In an RCT, the test persons are distributed in a random way (randomisation) to one or more treatment groups and a control group (or a gold standard treatment). Other study designs, such as cohort studies, case-control studies, cross-sectional studies, case reports and expert opinions, are normally regarded as having lesser evidence base. However, study designs alone are not sufficient to enable a critical evaluation of outcomes of scientific articles. Other factors, such as representativeness and number of selected patients, prospective or retrospective studies, laboratory or human studies and interpretation of statistical results, are also important when evaluating the evidence base.