Aim. To assess the methodological quality of non-randomized interventional studies of the outcomes of prevention and surgical treatment of postoperative ventral hernias using a systematic approach.Material and methods. We searched the indexed literature for non-randomized studies of VН surgery from January 1995 to December 2019. Each prospective study was combined with a corresponding retrospective study using predefined criteria to obtain comparable groups. The assessment of the following

more »

... nents was conducted: the choices of research methods, their rationale, design, inclusion criteria, reported results, and statistical methodsResults and discussion. 50 studies (17,608 patients) were selected: 25 prospective and 25 retrospective. In general, prospective studies showed slightly higher methodological quality scores than retrospective studies, with a mean score of 17 (IQR: 14-18) versus 15 (IQR 12-18). The studied subcategories of prospective studies obtained higher median scores for their "administration", "design" and "participants". 18 (36%) studies had a primary outcome, and only 2 studies (4%) described research power. None of the studies mentioned a standardized definition of VH recurrence, while methods for detecting recurrence varied widely. The methodological quality of the study did not depend on the year of publication or the increase in the impact factor of the magazine.Conclusion. Currently, non-randomized interventional studies of the results of surgical treatment of VH are methodologically ineffective. A clearer analysis of the research results and the establishment of a minimum standardized set of data is necessary.