Background and aims: Problem gambling has been identified as an emergent public health issue, and there is a need to identify gambling trends and to regularly update worldwide gambling prevalence rates. This paper aims to review recent research on adult gambling and problem gambling (since 2000) and then, in the context of a growing liberalization of the gambling market in the European Union, intends to provide a more detailed analysis of adult gambling behavior across European countries. Methods: A systematic literature search was carried out using academic databases, Internet, and governmental websites. Results: Following this search and utilizing exclusion criteria, 69 studies on adult gambling prevalence were identified. These studies demonstrated that there are wide variations in past-year problem gambling rates across different countries in the world (0.12-5.8%) and in Europe (0.12-3.4%). However, it is difficult to directly compare studies due to different methodological procedures, instruments, cut-offs, and time frames. Despite the variability among instruments, some consistent results with regard to demographics were found. Discussion and conclusion: The findings highlight the need for continuous monitoring of problem gambling prevalence rates in order to examine the influence of cultural context on gambling patterns, assess the effectiveness of policies on gambling-related harms, and establish priorities for future research.
