Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
A framework situating designs according to evaluation questions. The x-axis presents the internal validity - external validity continuum. The continuum between process, mechanism and effects is represented on the y-axis. Finally, the transverse axis positions the various methods according to the research question, from efficacy studies to implementation research
