  Does reviewing previous answers during multiple-choice exams help examinees
increase their final score? This article formalizes the question using a
rigorous causal framework, the potential outcomes framework. Viewing examinees'
reviewing status as a treatment and their final score as an outcome, the
article first explains the challenges of identifying the causal effect of
answer reviewing in regular exam-taking settings. In addition to the
incapability of randomizing the treatment selection (reviewing status) and the
lack of other information to make this selection process ignorable, the
treatment variable itself is not fully known to researchers. Looking at
examinees' answer sheet data, it is unclear whether an examinee who did not
change his or her answer on a specific item reviewed it but retained the
initial answer (treatment condition) or chose not to review it (control
condition). Despite such challenges, however, the article develops partial
identification strategies and shows that the sign of the answer reviewing
effect can be reasonably inferred. By analyzing a statewide math assessment
data set, the article finds that reviewing initial answers is generally
beneficial for examinees.
