Quasi-experimental studies: Experimental designs in which subjects are not randomly assigned to experimental and control groups.
Randomized studies: Experimental designs that randomly assign subjects (individuals, families, classrooms, schools, communities) into equivalent groups that are exposed to different interventions in order to compare outcomes with the goal of inferring causal effects.
Replication: The reproduction of a trial or experiment by an independent researcher.
Research funders: For purposes of this report, federal agencies and foundations that fund research on mental health promotion or prevention of mental, emotional, or behavioral disorders.
Resilience: The ability to recover from or adapt to adverse events, life changes, and life stressors.
Retrospective study: A study that looks back at the histories of a group that currently has a disorder or characteristic in comparison to a similar group without that disorder or characteristic to determine what factors may be associated with the disorder or characteristic.
Risk factor: A characteristic at the biological, psychological, family, community, or cultural level that precedes and is associated with a higher likelihood of problem outcomes.
Selective prevention: Preventive interventions that are targeted to individuals or to a subgroup of the population whose risk of developing mental, emotional, or behavioral disorders is significantly higher than average. The risk may be imminent or it may be a lifetime risk. Risk groups may be identified on the basis of biological, psychological, or social risk factors that are known to be associated with the onset of a disorder. Those risk factors may be at the individual level for nonbehavioral characteristics (e.g., biological characteristics such as low birth weight), at the family level (e.g., children with a family history of substance abuse but who do not have any history of use), or at the community/population level (e.g., schools or neighborhoods in high-poverty areas).
Substance abuse: The use of alcohol or drugs despite negative consequences.
Substance dependence: The persistent use of alcohol or drugs despite negative consequences, often with a physiological dependence characterized by tolerance and/or symptoms of withdrawal.
Substance use disorder: An inclusive term referring to either substance abuse or substance dependence.
Systematic review: A literature review that tries to identify, appraise, select, and synthesize all high-quality research evidence relevant to a research question.