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When numbers matter: an epidemiologist improves health care for the homeless

Yale Medicine Magazine, 2006 - Autumn


Can statistics help the health of New York City’s homeless? Bonnie Kerker, Ph.D. ’01, is convinced that they can. Over the last two years, Kerker, the city’s assistant commissioner for epidemiology services, and her colleagues have analyzed data from more than 100,000 clients of the city’s vast shelter system.

Her research—based on data from everyone who spent a night in the shelter system from 2001 through 2003 that were matched to Health Department registries—has created a picture of the health of this population. Now this information underpins a plan to augment health care resources available to shelter residents.

Among her findings—single adults who use New York’s shelter system are diagnosed with HIV infection 16 times more often than the city’s general population. And the death rate among the homeless is twice as high. These facts helped influence the new plan, scheduled to be fully operational by December 2006.

The new plan enhances both medical screenings and treatment options. Expanded services will range from shelter-based ambulatory detox services to greater assistance for pregnant women. Progress will be monitored against new performance indicators that will track the implementation of each step. Deaths due to exposure to natural elements or extreme weather will also be analyzed.

Lead author of a report, “The Health of Homeless Adults in New York City,” which was released in January 2006, Kerker is particularly pleased that the plan will “expand rapid HIV testing and increase the identification and treatment of alcohol and drug abuse at shelters—all of which the city said it would do in response to the findings. It’s the bright side of some dark data.”

Participation in the new health programs is voluntary, and eligible candidates will receive information to explain what’s being offered and how they can benefit. The city’s ultimate goal is to find homes for as many shelter users as possible. “We think that improving people’s health can improve their chances to acquire and maintain adequate housing,” Kerker said. “But the big elephant in the room is really homelessness.”

Kerker’s concern for underserved populations began at age 10, when she imagined herself as a Peace Corps volunteer helping malnourished African kids. She and her two sisters grew up in New City, a suburb north of New York City, where their father was a lawyer and their mother a former teacher. Kerker, now 37, did join the Peace Corps after graduating from Tufts in 1990 with a degree in American studies. During two years in the Dominican Republic, she developed community health and education programs in Sabana Alta, a small town of 8,000 people.

Hired as an epidemiologist and data analyst for the New York City Department of Health and Mental Hygiene in 1995, Kerker left in 1997 to pursue a doctorate at Yale. “I was always interested in the translation of data into action. My two amazing advisors—Mark Schlesinger and Sally Horwitz—gave me much hands-on opportunity to see how data can actually be used in real life. Dr. Horwitz was evaluating the health effects of Connecticut’s new Welfare to Work program. Being involved in that process helped me understand how to analyze and present data in a way that makes them useful to policy-makers.”

Her doctoral program yielded an unexpected professional reward. After 18 months at a child welfare agency in Connecticut, Kerker heard through a classmate about a new Department of Health bureau in New York established by another Yale alumnus, Farzad Mostashari, M.D. ’96. He hired her in late 2003. When Mostashari left in 2005 to head another project, Kerker was promoted to his former position.

Today, she runs a department with 25 employees and clearly loves her work. “Everybody really relies on data in the Bloomberg administration. So you feel like you’re needed, and that the work you do is actually being used in policy decisions,” Kerker reflected. “That’s why I went into this field in the first place.”