The Medical Mistrust Multiformat Scale: Links with vaccine hesitancy, treatment adherence, and patient-physician relationships.

The assessment of medical mistrust is essential to progress in understanding behavioral health outcomes such as vaccine hesitancy, treatment adherence, and patient-practitioner relationships. To address limitations of existing medical mistrust scales and to address a need for clear psychometric information, a new Medical Mistrust Multiformat Scale (MMMS) was developed and tested. Study 1 included 741 Black and White participants with hypertension, with one subsample used for item selection and a second for cross-validation. Study 2 included 234 lower-income participants with diabetes or hypertension representing diverse racial/ethnic identities. All participants were recruited via marketing panels to complete online questionnaires. In both studies, the MMMS fit a unidimensional factor structure; items demonstrated high discrimination; and the scale was correlated with vaccine compliance. In Study 1, measurement invariance was demonstrated across Black and White groups. In Study 2, the MMMS correlated with additional tested outcomes regarding treatment adherence and patient-practitioner relationships, all effects remained significant after controlling for other related variables (conspiracy beliefs, race/ethnicity, political affiliation, stress), and the MMMS produced significantly larger convergent validity effects than a widely used existing mistrust scale. Results highlight the importance of medical mistrust and support use of the MMMS to assess mistrust in populations that include people with diverse racial/ethnic identities, people with chronic medical conditions, and people with lower incomes. (PsycInfo Database Record (c) 2021 APA, all rights reserved).