Causal Evidence Guidelines, Version 2.2

CLEAR reviews causal studies in a number of labor-related topic areas and assigns them a rating indicating the strength of their causal evidence.

This document provides the CLEAR evidence criteria for rating causal studies. A companion addendum provides additional examples of how to apply the guidelines to rate the strength of causal evidence.

CLEAR assesses the quality of evidence for:

• randomized controlled trials (RCTs)

• interrupted time series (ITS) designs

• comparison group designs

• other nonexperimental causal designs (e.g., difference-in-differences)