Research and Evaluation conducts research and demonstration programs, and designs, implements and evaluates interventions to improve community health and strengthen health policy. Our Research and Evaluation team has a solid track record of publications in peer-reviewed journals and national and international presentations relating to its research and evaluation activities. Public Health Solutions researchers are well-regarded in the field for their expertise in using online methods to recruit and retain large samples for data collection and intervention on critical public health issues.

Sabina Hirshfield, PhD


Sabina Hirshfield, PhD is a Senior Research Scientist with expertise in internet-based recruitment, research and video-based interventions with vulnerable populations, including sexual minorities and those living with HIV. Her training is in social sciences and epidemiology, which has enabled her to conduct theoretically-based HIV prevention research and interventions, most of which have been online, with both HIV-negative and HIV-positive populations. Through her online work, she has reached thousands of individuals and has established a solid publication record in the HIV prevention field. View published works.

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Martin J. Downing, PhD


Martin J. Downing, PhD is an environmental psychologist and Research Scientist with PHS. His research focuses on psychosocial and contextual factors of health and well-being, particularly at the intersection of sexual behavior, substance use, and HIV/STI prevention. He has expertise in quantitative and qualitative methods of data collection and analysis, Internet-based recruitment and survey administration, and video-based HIV prevention interventions. View published works.

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Ashley  Grosso, PhD


Ashley Grosso, PhD is a Research Scientist with primarily quantitative research experience in HIV epidemiology and prevention and reproductive health studies in the U.S. and sub-Saharan Africa. Her research has focused on populations at high risk including men who have sex with men and female sex workers. With her academic training in public administration, she has also completed research on the determinants, effectiveness, and equity of funding for HIV-related services in the United States and internationally. View published works.

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