These data summarize 221 studies published since 1978 related to countermeasures designed to combat influence operations. We include studies which met four inclusion criteria: (1) a source of variation in exposure to the countermeasure; (2) a clearly defined outcome of interest for some specified population; (3) relevance to thinking about the potential of an intervention to impact real-world behavior; and (4) enough detail to evaluate the credibility of the findings. Papers are identified by title, author, year, and journal. Each study is also coded according to such variables as treatment type (real-world or experimental), outcome type (action, belief, knowledge), and type of intervention (disinformation disclosure, content labeling, etc.). An initial set of articles were drawn from the bibliography of Trends in Online Influence Efforts (Martin et al., 2020) and keyword searches including a wide range of terms such as “countering misinformation”, “content moderation”, and "account removal”. To expand the review, we conducted two stages of forward and backward citation mapping based on this initial list.