Methodology Behind the Tool

Types of Armed Violence: Definitions

Intra-state armed conflict is a contested incompatibility between a state and non-state armed group inside the state’s territory that causes at least 25 battle-related deaths per year. Intra-state armed conflict can be:

• fought over control of government and/or territory;
• have foreign involvement (i.e., internationalized intra-state wars); and
• be multi-party (i.e., involving a state and more than one non-state armed group).

The terms violent extremism and terrorism are often used interchangeably in the academic and policy literature. There is also much debate as to the precise definitions of these terms and the extent to which they are conceptually distinct from other forms of armed conflict. As a result, the project does not attempt to define these terms and instead keeps note of the various definitions used by different authors. The project does however distinguish between terrorism/violent extremism conducted by organized groups and terrorism conducted by lone actors.

Lone actors are defined as individuals who plan, prepare and execute their attacks with a high degree of autonomy and who are not active participants of established terrorist groups or organizations (although they may be inspired by them).

Systematic Literature Review

Our systematic literature review focuses on three dimensions of the different types of armed violence outlined above, namely:

• Why armed violence occurs (“onset”).
• The spillover of armed violence to neighboring countries (“spillover”).
• Recruitment into non-state armed groups (“recruitment”).

To conduct the systematic literature review, a team of researchers searched academic databases and policy publications to identify relevant studies published between 2014 and 2024. The literature review included studies published in English, French, and Spanish, as well as studies from a broad range of academic disciplines, including economics, political science, psychology and neuroscience. Once relevant studies were identified, the research team reviewed each study and extracted information on onset, recruitment and spillover, following a standardized codebook. More specifically, the researchers searched for information on the factors that make violence more or less likely to occur, and how these factors interact with other factors. The researchers also examined the degree to which these factors are supported by evidence, and whether the empirical basis for certain factors is absent or inconclusive. The findings from this systematic literature review were then transferred into an easily searchable tool to explore risk and protective factors.