The Research & Evaluation division has a staff of seven (four PhDs, one MSc, one CHES, and one Research Assistant). The team is led by Mary Ann Chiasson, DrPH, who joined Public Health Solutions as Vice President for Research and Evaluation in 1999. Dr. Chiasson is an epidemiologist with more than 20 years of experience in public health.

Research & Evaluation conducts research and demonstration programs, and designs, implements and evaluates interventions to improve community health and strengthen health policy. Our Research & 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.  They recently completed an evaluation of the New York State WIC Program, and continue to focus on interventions to prevent early childhood obesity, the influence of behavioral factors (e.g., depression, anxiety and obesity) on pregnancy outcomes, and Internet-based interventions to prevent HIV transmission. For more than a decade, Public Health Solutions has led a collaboration of researchers and clinicians, using the Internet as a recruitment tool for large-scale studies of high-risk sex and drug-using behaviors in men who have sex with men (MSM). 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 topics.

Mary Ann Chiasson, DrPH


Mary Ann Chiasson joined Public Health Solutions as the Vice President for Research & Evaluation in 1999. Mary Ann oversees a team of nationally-recognized researchers committed to conduct formative research, program monitoring, and outcome evaluations for PHS and public health programs outside of the organization.  The team also specializes in developing technology-based interventions and social marketing campaigns using video, social media, and interactive internet-based applications to promote sexual health and prevent obesity.  Prior to PHS, Mary Ann served for 14 years in various capacities at the New York City Department of Health, including nine years as an Assistant Commissioner of Health with scientific and administrative responsibility for AIDS surveillance, HIV/AIDS research, and vital statistics and epidemiology. Her research expertise includes the epidemiology of HIV and STIs, women’s reproductive health, and early childhood obesity. View published works.

Contact Dr. Chiasson

Martin J. Downing, PhD


Martin J. Downing, PhD is an environmental psychologist and Research Scientist with Public Health Solutions. 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.

Contact Dr. Downing

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 United States 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.

Contact Dr. Grosso

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.

Contact Dr. Hirshfield