Physicians often find it challenging to apply the lessons of large research studies to their clinical practice, especially when the research participants do not reflect the racial identity, ethnicity, age, or sex and gender of the physicians’ patients. Strict eligibility criteria for enrollment in a study may exclude relevant participants. The study population may not include groups representing large fractions of those who might be candidates for the trial intervention. This can leave clinicians in a quandary about whether and how to apply the research findings to their own patients, for whom the risk–benefit profile may differ.

Of these trial design lapses, racial and ethnic gaps are particularly disturbing. For years, the Journal has published studies that simply do not include enough participants from the racial and ethnic groups that are disproportionately affected by the illnesses being studied to support any conclusions about their treatment. In the United States, for example, Black Americans have high rates of hypertension and chronic kidney disease, Hispanic Americans have the highest prevalence of nonalcoholic fatty liver disease, Native Americans are disproportionately likely to have metabolic syndrome, and Asian Americans are at particular risk for hepatitis B infection and subsequent cirrhosis, but these groups are frequently underrepresented in clinical trials and cohort studies.

There are several possible reasons for this lack of representation in research studies. Simple logistic obstacles, such as an inflexible work schedule or the lack of convenient and affordable transportation to a research center, can act as impediments. Some potential participants may fear being exploited or harmed by the medical establishment, given a history of mistreatment in which the Tuskegee experiment in untreated syphilis in Black men is only the tip of the iceberg.

Another major contributor is the dearth of investigators and study staff who are themselves members of minority groups. Involvement of such persons in conducting the study may increase the confidence of potential minority research participants and community leaders, who can be key to engaging broader participation and accommodating the needs of their communities. Mentoring such investigators, who could then work with underserved communities, would both enhance the recruitment of representative participants and improve communication so that it contextualizes the research questions and the potential benefits of participation in the study appropriately.

For too long, we have tolerated conditions that actively exclude groups from critical resources in health care delivery, research, and education. This exclusion has tragic consequences and undermines confidence in the institutions and the people who are conducting biomedical research. And clinicians cannot know how to optimally prevent and treat disease in members of communities that have not been studied.

Solving this problem will require changes throughout the research enterprise. We need to have a collective conversation about what constitutes acceptable and reasonable representativeness in clinical research. Every funder should mandate appropriate representation. Clinical trialists should devise better methods of recruitment from traditionally underrepresented groups. And medical schools and training programs must commit to the long-term work required to make sure more members of underrepresented groups become leaders in medical research.

Table 1. Table 1. Sample Supplementary Table on the Representativeness of Study Participants.

As a medical journal, we cannot fix all these problems. But we can take concrete steps. Our research papers often, but not always, comment on gender, race, and ethnicity within the study sample. But as of January 1, 2022, we will require, as a new step, that authors of research studies prepare a supplementary table that provides background information on the disease, problem, or condition and the representativeness of the study group, to be posted with the article at the time of publication online. An example of the kind of information authors should provide is shown in Table 1.

We will seek the same clarity and transparency in these descriptions of the selection and representativeness of study participants that we seek in any important methodologic feature of research. We believe this requirement will foster greater thought and effort in the recruitment of appropriately representative participants in studies.

We recognize that this step toward transparency is a small one and that it will not overcome many limitations in the application of study results. Studies conducted in one country, for example, may have limited applicability to other countries in which income levels, races, ethnicities, and cultural practices differ. This is one reason we continue to encourage global health research. We have, for some time, taken representation into account in evaluating the suitability of manuscripts for publication in the Journal; ultimately, we will require a more diverse study population for trials conducted in countries with underrepresented groups affected by the condition being studied. And we hope to work with funders, researchers, and other journals to appropriately diversify trial participation, increase the number of persons from underrepresented groups among researchers, and design studies that meet the clinical needs of those most burdened by disease.

Our mission as a journal is to communicate to physicians and other public health and allied health professionals the latest research and the most authoritative thinking to help them care for their patients. From this perspective, diversity in research isn’t simply a matter of social justice. It’s a critical part of learning how to improve the health of every person.