Considerations for Using Large Data Sets to Assess Disparities in Eye Care and Vision Health

Besagar et al¹ used the Behavioral Risk Factor Surveillance System, a state-based telephone interview survey coordinated by the US Centers for Disease Control and Prevention, to determine associations of demographic factors, mental health, and social determinants of health with self-reported severe visual impairment. Large data sets, such as the Behavioral Risk Factor Surveillance System, are publicly available, providing a nationwide sample to evaluate health disparities, perform longitudinal surveillance, and identify areas of needed policy interventions. In this current work, the team found that severe visual impairment was associated with identifying as Black/African American, American Indian or Alaska Native, or Hispanic, having depression, being single, having poor economic stability, having low educational attainment, and having poor health care accessibility.¹

While large data sets supplement our understanding of social determinants of health, large data sets have important limitations.² Data sets may exclude populations from diverse racial and ethnic backgrounds or with low incomes. In the current work, for example, Besagar et al¹ highlight that 76% of the sample were non-Hispanic White. People from racial and ethnic minority backgrounds and people with lower socioeconomic status are disproportionately affected by social risk factors. So data sources to estimate the direction and magnitude of the risk for severe visual impairment must be inclusive of the correct cohort of patients to ensure accurate conclusions.

It is critical to this newer field of study that researchers use clear terminology. Social determinants of health, social risk factors, and social needs are individual concepts.³ Differentiating these concepts helps to interpret results and enable appropriate action. The World Health Organization defines social determinants of health as, “The conditions in which people are born, grow, live, work, and age,” which are “shaped by the distribution of money, power, and resources.”³ Social determinants of health are neither negative nor positive; they exist on a spectrum; and they are not possessed by an individual, but rather, they affect society.³ The social determinants of health domains outlined in Healthy People 2030 include economic stability, education access and quality, health care access and quality, neighborhood and built environment quality, and social and community context.⁴ Social risk factors describe how social determinants of health affect the individual, such as having low income, low education, food or housing insecurity, or high exposure to environmental pollutants.³ Social needs include what the person thinks is their current most pressing need.³ For example, through conversation, a person may identify safety from interpersonal violence as more critical than food or housing security. Research could better inform appropriate interventions if each researcher could pause to evaluate whether their work is focusing on social determinants of health, social risk factors, or social needs.

In the current work,¹ the data come from an aggregated data set of social determinants of health, so individuals’ social risks or social needs cannot be assessed. Although individual-level interventions (eg, an ophthalmologist becoming engaged in community outreach or creating a sliding financial scale for ophthalmic services) may help 1 patient at a time, they will not address the root cause of the population-level association between poverty and severe visual impairment because the interventions are not aligned to the level of analysis. With social determinants of health factors at a systemic level, interventions to improve severe visual impairment likely need to be broad policy changes. For example, a living wage (the income that an individual requires to live without any assistance) as a minimum wage could be one policy lever to address the social risk factor of low income identified as a predictor of severe visual impairment. Survey data describing social determinants of health unfortunately cannot, by themselves, inform interventions to mitigate negative individual social risks.

Integrating social risk factor assessment into practice for ophthalmologists represents an avenue to improve patients’ visual health. For example, for a patient with microbial keratitis, the ophthalmologist may prescribe multiple expensive eye drops hourly and ask for frequent follow-up visits. For a person with lower income and difficulties with transportation, this recommendation could be unachievable. In this context, a thoughtfully crafted social risk questionnaire to assess difficulty with transportation and ability to afford medications would inform a plan to help patients optimally with their health by also addressing the patient’s social needs. The ophthalmologist may need to identify less expensive medications or connect the patient to social work services for assistance with transportation, if that exists, to successfully treat disease and preserve vision.

While secondary data provide powerful insights, ophthalmologists and researchers are motivated to mindfully create change in the real world. In this space, community-engaged research has proven to be the best aid to develop interventions. The National Academy of Medicine emphasizes this point—to be successful in addressing social determinants of health, research must be built through genuine relationships with the communities affected by negative social risk factors.⁵ Community-engaged research is collaboration with the intent to make an impact in the specific community both through and with individuals affiliated by special interests, geographic location, or similar situations.⁶ Nwanyanwu and colleagues⁶ highlight that community-engaged research can enable researchers to better understand and address the social needs of patients with social risk factors who have poor vision or eye health. The partnership between the eye care professionals and vision researchers with the community must be both nurtured and developed in a way that is consistent with that community’s cultural framework.⁶ Partnerships through community-engaged research enable researchers to understand communities (eg, in the United States, the different needs between rural White individuals vs nonrural White individuals within a region). That level of detail is lost in aggregated data.

A multidisciplinary approach enables researchers, clinicians, and communities to effect change. Elam and colleagues⁷ provide ophthalmologists with recommendations to address health disparities in eye care that include ways to enhance collaboration with professionals, including optometrists, social workers, health care administrators, engineers, and policy makers. Examples of collaboration could be working with optometrists on services to expand access to affordable eyeglasses, partnering with social workers to support patients to offset income needed for medical care, or working with health care administrators to create programs for nonemergency medical transportation for patients, for example.

The key factors to consider in health equity research are an awareness of the different terminology (social determinants of health, social risk factors, or social needs), being mindful of using data sets that may not be generalizable or representative, and a focus on the interpretation of the data. Eye care professionals and vision researchers should be aware that community-engaged research requires time and resources and should be thoughtfully conducted so as not to cause additional harms to communities. Shining a spotlight on the associations of poor vision and social determinants of health provides our community of clinicians and scientists the impetus to improve the lives of all the patients whom we serve.