A SYSTEMATIC REVIEW OF ONLINE MARKETING EFFECTS ON ONLINE AND OFFLINE SALES: A FRAMEWORK AND STATE OF RESEARCH

Purpose - A significant body of literature has emerged over the past two decades on the effects of digital marketing on online and offline sales, giving rise to the pressing need to systematize the existing research and provide clarity on its various streams. Therefore, this systematic review has three main objectives: evaluating existing research, categorizing studies, and examining research methods. Design/Methodology/Approach - This paper presents a systematic review of 89 articles on the effectiveness of online marketing instruments. The review follows the PRISMA methodology and utilizes the Python -based software ASReview. Findings and Implications - The systematic review resulted in a categorization framework that classifies studies exploring the effectiveness of various online marketing instruments. Two major categories - own -channel advertising and cross -channel advertising - along with their subcategories, are outlined. The study also identified common research methods (analysis of sales and advertising data, various experiments) and frequently used statistical techniques (Difference -in -Differences and Vector Autoregressive modeling, Structural Equation Modeling, Regression Analysis). Limitations - Several limitations were encountered during this systematic review, including the inability to extract or access text from 61 articles, as well as potential language and publication bias as only English -language articles were included. Originality - This systematic review is the first comprehensive examination of the impact of online advertising on online and offline sales, contributing significantly to the existing literature. It introduces an innovative framework for categorizing studies, highlights key limitations, identifies research gaps, and offers an extensive overview of statistical methods for future research in this area.