AbstractCognitive diagnostic assessment (CDA) as an innovative criterion-based approach to assessment has been the center of increasing attention in recent decades due to its inherent merits over its previous psychometric counterpart. Due to the lack of research on the post hoc analyses of classroom assessments to diagnose L2 learners’ strengths and weaknesses in the multidivisible skill of reading comprehension, and also its significance in high-stakes tests, this article offers the implementation of samples of high-stakes tests in the classroom environment due to its beneficial consequences and washback for the learners to increase their educational chances. Therefore, the present article is intended to shed light on the mental processes which the examinees went through in responding to the multiple choice questions of four reading comprehension passages, elicited from the recent Iranian University Entrance Exam 2015. Time-series design was conducted to forty female students aged between 1.....