The College Completion Strategy Guide authors have carefully reviewed the research informing the policy guidance in each brief, generally highlighting policies and practices evaluated in well-designed experimental studies and successfully replicated in other contexts.

A variety of studies and methodologies inform the strategy guide:

• Experimental research, which employs methods that test a causal relationship (for example, randomized controlled trials), is used to support causal statements.
• Quasi-experimental research, which employs methods that infer a causal relationship (for example, regression discontinuity, pretest-posttest, or interrupted time series), is used to support possible causal statements.
• Meta-analyses are used to share findings and analyses across experimental and quasi-experimental research studies. They may include the estimated effects of interventions.
• Descriptive data are used to discuss trends related to the characteristics, activities, outcomes, or experiences of a population, but are not used to infer causality.
• Qualitative research is used to illuminate the experiences of program participants.
• Implementation studies and cost studies provide insight into what staffing, financial, or other investments are required to implement an intervention well.

To the extent possible, the College Completion Strategy Guide elevates research with data disaggregated by different racial and ethnic groups, particularly to highlight where research is limited.