Problem Based Learning, (PBL) is considered a teaching strategy that improves the knowledge and involvement of students. However, scarce studies have been carried out to assess the factual impact of this strategy. This is mainly due to the absence of instruments to analyze the perceptions of students and the efficacy this PBL has. Also, Spanish universities are implementing recently this learning strategy on the idea that they are a good Higher Education (HE) innovation experience.

In this study we develop a scale to measure perceptions of students of a PBL experience as compared to traditional Social Psychology classes. We made an exhaustive revision of PBL studies to create a pool of items that captures the main aspects that affect the efficacy of a PBL experience. Then we selected ten items that comprised three factors: perception of PBL experience (alpha = .74), perception of the teacher´s competencies (alpha = .75) and involvement of the student in the subject (alpha = .75). We also obtained a global score that included the two factors (perception of the experience and the teacher) with a reliability of .81 for the pretest and .83 for the posttest.

In sum, our instrument is as comprehensive and easy to administer scale that allows capturing the factual efficacy of this strategy in HE.