Figure 2From: Substance use disorders in Arab countries: research activity and bibliometric analysisNumber of published documents in substance-related disorders stratified by topic. Group 1: Tobacco or Waterpipe research documents; Group 2: Alcohol research documents; Group 3: illicit drugs and abused medicinal agents research documents; Group 4: miscellaneous research topics. Note: total results exceed 413 because of some overlap in results of the first three groups.Back to article page