Exploring racial and ethnic disparities in medication adherence among Medicare comprehensive medication review recipients

•This retrospective study used 100% of the 2017 Medicare claims including MTM data.•Racial/ethnic disparity in medication adherence was identified among CMR recipients.•Blacks were more likely than Whites to be nonadherent to all medications studied.•Hispanics were more likely than Whites to be hyperlipidemia medication nonadherent.•Observed characteristics explained close to 15% of the identified disparity.