Two different lenses of social determinants of health

January 5, 2022 / By Clark Cameron

Recently, I visited my optician after an 18-month, pandemic-induced absence. The doctor is a rather pleasant fellow, but the annual exam is just as much fun as I recall. First (why first?), was the air puff glaucoma test, which was secretly designed to gauge one’s whiplash threshold. Next, was the phoropter. Unfamiliar with this term? It’s the machine the doctor swings around in front of your face, which looks like a Mardi Gras mask from outer space.

“A or B?”

              “Uh … A. No, wait. B!”

“Okay, 1 or 2?”      

              “Hmm. 2 … I think.”

“You think?”

“I take longer choosing paper or plastic at the market. Should my vision really be a lightning round exercise?”

“Let’s try this …”

My doctor clicked the phoropter and a lens suddenly dropped in front of my eye. Instantly the edges of the eye chart letters sharpened. No haze. Zero blur. Introducing the right lens brings clarity and focus.

Such is the case with a recent report produced by Richard Averill and Ron Mills. The report, entitled “Socioeconomic Status (SES) and health care delivery system performance,” applies the lens of the Center for Disease Control and Prevention’s (CDC) Social Vulnerability Index (SVI) to hospital performance across all U.S. counties. It seeks to understand if disparities of care exist between low SES and high SES counties. Low SES counties are defined as those which need more resources after a disaster such as a severe weather event or the COVID-19 pandemic.

“Low SES counties were disproportionately located in the three southern census regions. Delivery system performance in each SES percentile was evaluated by comparing actual delivery system performance for the beneficiaries living in the counties in each SES percentile to a risk-adjusted expected performance using the national average rate for each performance measure as a benchmark.”

In addition to the SVI Index, the authors also risk adjusted the evaluated data set using 3M™ Potentially Preventable Events (PPE).

Using the SVI lens, the report clearly concludes:

“for negative events such as an avoidable hospital admission and surgical mortality, beneficiaries in counties with lower SES experience higher than expected rates. For the service volume measures such as ambulatory physician and care management visits, beneficiaries in counties with lower SES experience lower than expect rates. The performance issues identified for low SES geographic regions means that the health care delivery system is not functioning as intended in low SES counties, thereby creating heath care equity concerns.”

The SVI is a good lens through which to view social factors contributing to health disparities, but it has a key limitation: county level visibility. This level is superior to a state level view, but it’s not uncommon to find a wide spectrum of wealth and income distribution within most U.S. counties. A more granular perspective is needed to better identify and address social determinants of health (SDoH) factors.

The ultimate 20/20 view is provided by the patient level lens. This lens is best applied between physician and patient. Z codes were added as modifiers to the ICD-10 code set for precisely this purpose. Covering social factors ranging from housing to employment to food insecurity and transportation, Z codes don’t aggregate groups of people simply by geography but provide a true “N of 1.”

When captured during a medical office visit, Z code data brings into crystal clear focus the immediate needs of an individual that can, in many cases, be remediated by a government agency, a community or non-profit organization or a commercial health plan. Historically, most physicians haven’t bothered to capture Z codes during patient encounters, but that’s changing. CMS now adjusts payment based on Z code capture, and risk adjustment tools like 3M™ Clinical Risk Groups (CRGs) already contain Z code logic.

Regardless of whether blurred vision is corrected with drug store readers (SVI) or with custom prescription glasses (Z codes), there are two valuable lenses now available to help address social factors and lead to better health.     

Clark Cameron is manager of payer market strategy and development for 3M Health Information Systems.


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