PURPOSE: Mayer's theory of multimedia learning proposes that personalisation and embodiment (P/E) can improve outcomes in e-Learning. The authors hypothesised that an e-Learning module enhanced by P/E principles would lead to higher knowledge, perceived P/E and motivation among health care professionals, compared with an unenhanced module. METHODS: The authors conducted a randomised trial comparing two versions of a 30-minute multimedia e-Learning module addressing the antibiotic management of pneumonia. The unenhanced format used slides with voiceover (human voice but no visible speaker), formal language and no specific P/E strategies. The enhanced format additionally implemented P/E strategies including conversational style, polite language, visible author, social congruence, human-like presence and professional presence by subtly changing the script and substituting several short videos of subject matter experts. Participants included pharmacists, physicians and advanced practice providers from three academic and several community hospitals. Outcomes included knowledge, perceived P/E (assessed by the Congruence Personalisation Questionnaire, CPQ), motivation (assessed via the Instructional Materials Motivation Survey [IMMS] and Motivated Strategies for Learning Questionnaire [MSLQ]) and course satisfaction. RESULTS: There were 406 participants including 225 pharmacists, 109 physicians and 72 advanced practice providers. Post-module knowledge was slightly higher for the enhanced versus the unenhanced format, but the difference did not reach statistical significance (adjusted mean difference, 0.04 of 10 possible, [95% CI -0.26, 0.34], p = 0.78; Cohen d 0.02). Participant perceptions of P/E (measured via CPQ) were significantly greater for the enhanced format (difference 0.46 of 5 possible [0.35, 0.56], p < 0.001; Cohen d 0.85), as were motivational features of the e-Learning course (measured via IMMS) (difference 0.14 of 5 possible [0.02, 0.26], p = 0.02; Cohen d 0.24). Participants' overall motivational orientation (measured via MSLQ) and course satisfaction were not significantly different between the two formats (p > 0.05). CONCLUSION: Application of P/E principles to an e-Learning module led to greater perceived P/E and motivational features but did not influence knowledge.