Critical appraisal skills training to undergraduate medical students: A Randomized Control Study

Critical appraisal skills are presumed to perform a principal part in evidence-based health education and practice methods. This study aimed to design an educational intervention around critical appraisal in this context, evaluate the efficacy of the teaching methods, and investigate critical appraisal skills training to undergraduate medical students.

In this prospective Randomized Control Trial (RCT), 256 sixth-year undergraduate medical students from Shiraz University of Medical Science, Shiraz, Iran, participated. 124 of the students were not taught critical thinking methods as a control group, and 132 participants were taught critical thinking methods by multi-media and attended an online Critical Appraisal Skills (CAS) training workshop as an intervention group. We used the Critical Appraisal Skills Programme (CASP) questionnaire to evaluate students' knowledge, attitude, confidence, and appraisal skills. This questionnaire was translated into Persian for the first time in Iran by Shokooh Varai, et al. They investigated its validity and reliability, the reliability of the questionnaire being obtained by the Richardson Index (0.75), and the validity being confirmed by some faculty members of Tehran Nursing and Midwifery School. To compare both control and intervention groups, we used an independent t-test and a Chi-Square test at a significance level of 5%, and to analyze the demographic information, we applied some descriptive statistics: frequency, frequency percentage, mean and standard deviation. All of the statistical approaches were analyzed, using SPSS 22.

In all dimensions of the critical appraisal skills, medical students who completed the critical appraisal multi-media training and workshop performed better than those who did not (control group), and this difference was statistically significant (p<0.05). Moreover, the Chi-Square test results showed no statistical relationship between the groups regarding the demographic variables (p>0.05). Also, the Cohen's D effect size values in the knowledge and confidence dimensions were greater than 0.5; this meant a large effect. Regarding the attitude and appraises Skill dimensions, the effect size was between 0.2 and 0.5, which meant a medium effect.

Teaching critical appraisal skills through multi-media and CAS online workshops to medical students effectively improves the students' knowledge and confidence in appraising articles. This teaching also indicated a medium effect on students' attitudes and behavior. Our findings can justify implementing critical appraisal skills teaching modules in the undergraduate medical education curriculum.