Within brief experimental analysis, assessment data are used to target interventions for struggling students. This use of assessment data aligns with prevention and early intervention frameworks, but popular measures are limited for this purpose because of issues with measuring improvement in short periods. Our study was a pilot comparison of two curriculum-based assessment approaches with respect to measuring growth during the context of evidence-based interventions. Results suggested that subskill mastery measures were more consistent in assessing short-term improvement than general outcome measures. Results are discussed in terms of future research to examine how assessment data are used to target interventions.