Primary literature is essential for scientific communication and is commonly utilized in undergraduate biology education. Despite this, there is often little time spent "training" our students how to critically analyze a paper. To address this, we introduced a primary literature module in multiple upper-division laboratory courses. In this module, instructors conduct classroom discussions that dissect a paper as researchers do. While previous work has identified classroom interventions that improve primary literature comprehension within a single course, our goal was to determine whether including a scientific paper module in our classes could produce long-term benefits. On the basis of performance in an assessment exam, we found that our module resulted in longitudinal gains, including increased comprehension and critical-thinking abilities in subsequent lab courses. These learning gains were specific to courses utilizing our module, as no longitudinal gains were seen in students who had taken other upper-division labs that lacked extensive primary literature discussion. In addition, we assessed whether performance on our assessment correlated with a variety of factors, including grade point average, course performance, research background, and self-reported confidence in understanding of the article. Furthermore, all of the study conclusions are independent of biology disciplines, as we observe similar trends within each course.