Journal club (JC) is an integral part of postgraduate medical education. Although several innovations have been attempted to improve its effectiveness, the influence of the number of sessions remains unexplored. The current study investigated the effect of the number of sessions (one vs. four) of conduction of journal club on critical appraisal skills of postgraduate students at two institutions. A quasi-experimental study was conducted comparing the effectiveness of JC in a one- versus four-session JC format using two objective tests: Critical Appraisal Skills Test (CAST) and Population, Intervention, Comparison, Outcome (PICO) score. The degree of changes (pre-JC vs. post-JC session) after each format exposure, association of prescores to postscores, and correlation between the CAST and PICO scores were discerned. CAST score was higher in the four-session format (P = 0.03), whereas PICO score increased in the single-session format of JC (P = 0.03). Also, the change in CAST score was higher in the four-session versus single-session JC format (P = 0.04). We conclude that a four-session format of JC is more effective in augmenting critical appraisal skills of postgraduate students, whereas a single session is sufficient for improving factual knowledge.