Objectives: To investigate practicing physicians preferences, perceived usefulness and understanding of a new multilayered guideline presentation format - compared to a standard format - as well as conceptual understanding of trustworthy guideline concepts. Design: Mixed survey and randomized controlled trial through a standardised lecture for physicians. We presented participants with a clinical scenario and randomised them to view a guideline recommendation in multilayered or standard format. Both groups were presented and asked about guideline concepts. Participants answered multiple-choice questions by use of clickers. Setting: Mandatory educational lectures in six non-academic and academic hospitals and three primary care centres in Lebanon, Norway, Spain and United Kingdom. Participants: 181 practicing physicians in internal medicine (156) and general practice (25) attending the lectures. Interventions: A new digitally structured, multilayered guideline presentation format and a standard narrative presentation format currently in widespread use. Primary and secondary outcome measures: Our primary outcome was preference for presentation format. Understanding, perceived usefulness and perception of absolute effects were secondary outcomes. Results: 72% (95% CI 65-79) of participants preferred the multilayered format and 16% (95% CI 10-22) preferred the standard format. A majority agreed that recommendations (multilayered 86% vs. standard 91%, p-value = 0.31) and evidence summaries (79% vs. 77%, p-value = 0.76) were useful in the context of the clinical scenario. 72% of participants randomised to the multilayered format vs. 58% for standard formats reported correct understanding of the recommendations (p-value = 0.06). Most participants elected an appropriate clinical action after viewing the recommendations (98% vs. 92%, p-value = 0.10). 82% of the participants considered absolute effect estimates in evidence summaries helpful or crucial. Conclusions: Clinicians clearly preferred a novel multilayered presentation format to the standard format. Whether the preferred format improves decision-making and has an impact on patient important outcomes merits further investigation. Trial registration: None.