Since the early 20th century, researchers on education have striven to fully understand the effects of student retention. The studies led to an important evolution characterized by the improvement of resources and by a greater sophistication of statistical analysis techniques. The purpose of these studies is to know better the true effect of student retention, which means a methodological reflection on the origin of biases and the most appropriate methods to control them. This article resumes this methodological evolution and comments on the main results of researches.
RETENTION; GRADE REPETITION; GRADE AUTOMATICA PASSING; QUASI EXPERIMENTAL RESEARCH
