Aim: The aim of this study was to assess reporting of data on sex and race/ethnicity in randomized controlled trials (RCTs) of interventions published in the highest-ranking journals from the field of anesthesiology. Methods: We analyzed RCTs published from 2014 to mid-2017 in the seven journals belonging to the top 25% in the field of Anesthesiology according to the 2016 Journal Impact Factor published by the database Journal Citation Reports. We extracted data regarding terminology for sex/gender, proportion of participants according to the race/gender and race/ethnicity, and results shown for the race/gender and race/ethnicity. Results: Among the analyzed 657 trials, none stratified participants based on sex/gender or race/ethnicity. Proportion of included women and men was very similar. Most of the included participants were white/Caucasian. Less than 10% of analyzed trial reported information about participants’ ethnicity. Sex-related results were reported in 7.9% and race/ethnicity-related results were reported in 0.15% of analyzed trials. Of the 52 trials that reported sex-related results, 20 (38%) described that there was a significant difference between women and men in at least one analyzed outcome; among 8 trials that reported results based on race/ethnicity, 1 (12.5%) trial reported significant difference in at least one analyzed outcome for participants of different race/ethnicity. Less than 5% of analyzed trials addressed sex/gender or race/ethnicity in Discussion. Conclusion: Sex-specific and race/ethnicity aspects are neglected in anesthesiology trials, even though on average these trials included similar number of women and men. Outcomes related to anesthesiology and pain may differ in participants related to sex and race/ethnicity. Therefore, trialists in the field of anesthesiology should invest more effort to plan, conduct and report sex--specific and race/ethnicity results. Predominant inclusion of white participants in anesthesiology trials should be reconsidered.