Changes in character strengths after watching movies: when to use rasch analysis

OBJECTIVE: Professionalism is a critical part of a medical education, and various activities have been proposed to enhance professionalism among medical students. Watching films is an activity to promote character related to professionalism. Limitation of such is a single group pre-posttest design raising concerns about the errors of measurement. The study aimed to demonstrate a method to deal with this design using Rasch analysis. RESULTS: This study used a pre-posttest design with 40 first year medical students. All participated in a 3-day activity that involved watching four selected movies: Twilight, Gandhi, The Shawshank Redemption and Amélie. These films offer compelling illustrations of the themes of self-regulation, humility, prudence and gratitude, respectively. All participants completed a 10-item composite scale (PHuSeG) addressing these themes before and after watching the movies. When determining who benefitted from the intervention, paired t-tests on the results of a Rasch analysis were used to evaluate changes between pre- and posttest. Using Rasch analyses, we could document the stability of the items from pre- to posttest, and significant changes at both the individual and group levels, which is a useful and practical approach for pre- and posttest design. Moreover, it helps validate the psychometric property of the instrument used.