Why Systematic Review rather than Narrative Review?

rative reviews have been significantly increasing in most psychiatric journals in the world alongside " Psychiatry Investigation (PI) ". Since the launch of the " PI " at March 2004, there have been a number of review articles; indeed 54 papers were published as format of regular review papers or special articles in the " PI " from 2004 to 2014. However, of the 54 papers, only one review paper partially met the contemporary criteria of systematic review, otherwise were written as a format of narrative review for diverse topics such as epidemiological findings , concept and hypothesis of certain psychiatric disease, current understandings on certain disease, psychopharmacol-ogy, and treatment guidelines. This is unsatisfactory when reflecting the fact that systematic reviews have been rapidly and increasingly replacing traditional narrative (explicit) reviews as a standard platform of providing and updating currently available research findings as confident evidence. Most journals have started to change their policy in acceptance of review papers, they have been giving a priority to systematic review only as a regular review article and excluding narrative reviews, to provide the best evidence for all basic and clinical questions and further hypotheses. Of course, there should be Pros and Cons between systematic and narrative reviews; for instance, the major advantage of systematic reviews is that they are based on the findings of comprehensive and systematic literature searches in all available resources, with minimization of selection bias avoiding subjective selection bias, while narrative reviews, if they can be written experts in certain research area, can provide experts' intuitive, experiential and explicit perspectives in focused topics. 1 The absence of objective and systematic selection criteria in review method substantially results in a number of method-ological shortcomings leading to clear bias of the author's interpretation and conclusions. Such differences are quite clear when referring to the review paper of Drs. Cipriani and Ged-dess, 2 where 7 narrative and 2 systematic reviews were compared and found that narrative reviews including same studies reached different conclusions against each other, indicating the difficulties of appraising and using narrative reviews to have conclusion on specific topic. Hence, narrative reviews may be evidence-based, but they are not truly useful as scientific evidence. Even in reported as systematic review, it is also frequent that those papers are not true systematic review or they have certain bias in data search method and conclusions. For instance, due to lack of satisfactory …