Meeting the What Works Clearinghouse (WWC) attrition standard (or one of the attrition standards based on the WWC standard) is now an important consideration for researchers conducting studies that could potentially be reviewed by the WWC (or other evidence reviews). Understanding the basis of this standard is valuable for anyone seeking to meet existing standards and for anyone interested in adopting this approach to developing a standard (that is, combining a theoretical model with empirical estimates of key parameters) in a new context. The purpose of this paper is to explain the WWC attrition model, the process for selecting key parameter values for that model, and how the model informed the development of the WWC attrition standard and can be used to develop attrition standards tailored to other substantive areas. The model of attrition bias presented here, and the standard based on it, is an effort to protect consumers of research from drawing mistaken conclusions because of bias (in this case, attrition bias) in impact estimates. Tables and figures are appended.
Authors
- Authorizing Institution
- Society for Research on Educational Effectiveness (SREE)
- Peer Reviewed
- T
- Publication Type
- Reports - Descriptive
- Published in
- United States of America
Table of Contents
- Abstract Title Page 1
- Title 1
- Authors and Affiliations 1
- Abstract Body 2
- Background Context 2
- Purpose Objective Research Question Focus of Study 2
- Setting 2
- Population Participants Subjects 3
- Intervention Program Practice 3
- Significance Novelty of study 3
- Statistical Measurement or Econometric Model 3
- P z 4
- Usefulness Applicability of Method 5
- 1. Estimating and 5
- 2. Bounding Attrition Bias 6
- Research Design 6
- Data Collection and Analysis 6
- Findings Results 6
- Conclusions 6
- What we cannot do. 7
- What we can do 7
- Appendices 8
- Appendix A. References 8
- Statistical Analysis with Missing Data 2nd Edition 8
- American Economic Review Papers and Proceedings What to Do 8
- When Data Are Missing in Group Randomized Controlled Trials NCEE 2009-0049 8
- Biometrika 8
- Appendix B. Tables and Figures 9