Rossi Hassad

  • Professor, Psychology

Professor, School of Social and Behavioral Sciences

Fellow of the American College of Epidemiology

Chartered Statistician, The Royal Statistical Society, UK



  • Epidemiology (including COVID-19)

  • Statistics

  • Research Methods

  • Psychology/Mental Health

I am a full professor in the School of Social & Behavioral Sciences at Mercy University. My professional expertise encompasses epidemiology, statistics, education, research methods, and mental health, with a teaching and research emphasis on statistical literacy and evidence-based practice in the health and behavioral sciences. I also provide media commentary on infectious diseases, including COVID-19 (see selected media appearances and publications).

  • "These vaccines continue to significantly reduce the risk of severe illness, hospitalization, and death -- and that's an amazing scientific feat amidst a deadly pandemic. Attention to timely and effective messaging to healthcare providers and the general public should be a top priority for the FDA. Semantics matter. " Medpage Today, January, 2022

  • “As we move forward with the booster dose in certain populations, the variability in the effectiveness of the COVID-19 vaccines is sure to fuel the debate about the need for heterologous boosting, also known as mix and match.” Medpage Today, September, 2021 

  • “Undoubtedly, [the vaccine mandates] are very effective tools if fully implemented and properly enforced, but that is fraught with challenges,” says Rossi Hassad, an epidemiologist at Mercy University in New York. “So, there will be many cracks in the system that unfortunately may prolong this pandemic.” National Geographic, September, 2021

  • “Real-world data is messy data,” he said. “And because it’s messy, we want it, because it reflects the real context in which people live and operate.”

  • “When you have data that are broad in scope, you have to approach them with a mindset of discovery,” said Hassad. “If everything is hypothetical and deductive in our reasoning”—as is the case with controlled trials—“then there is no room for creativity and discovery.” APA Monitor on Psychology, September, 2021

  • “Rossi A. Hassad, an epidemiologist and statistician at Mercy University in Dobbs Ferry, N.Y., reported this month that both viruses “share key transmission characteristics.” Dr. Hassad and other experts say that what is known about the flu virus can inform our understanding of how and why Covid-19 is likely to become even more hazardous in the months ahead and that this knowledge can, in turn, reinforce the advice that everyone adopt readily available measures to thwart it.” New York Times, November, 20, 2020

  • Hassad adds: “The standard set by the mRNA vaccines — in terms of speed of development and the level of efficacy and effectiveness — will quite likely raise the bar in terms of public expectations: wanting more, better, and faster when it comes to … vaccines for other diseases.” If a doctor recommends a particular vaccine, he explains, “I can hear people saying, ‘How good is that vaccine? How effective is it? Is it good for people like me? Are there any factors about my life that I need to consider?’ I think it’s just really upped the bar in terms of patient education in their personal health — which, of course, will contribute to their decision-making about health.”  National Geographic, May, 2021

  • The more plausible lab-leak hypothesis, scientists say, is that the Wuhan laboratory isolated the novel coronavirus from an animal and was studying it when it accidentally escaped. “Not knowing the extent of its virulence and transmissibility, a lack of protective measures [could have] resulted in laboratory workers becoming infected,” initiating the transmission chain that ultimately resulted in the pandemic, says Rossi Hassad, an epidemiologist at Mercy University. But Hassad adds he believes that this lab-leak theory is on the “extreme low end” of possibilities, and it “will quite likely remain only theoretical following any proper scientific investigation,” he says. National Geographic, June, 2021

Medpage Today : Vaccines Are a Scientific Feat, but 'Prevention' Is a Misnomer - In public messaging, semantics matter - 

Medpage Today : Statistical Considerations for Evaluating COVID Vaccine Protection - Don't overlook the 95% confidence intervals - 

Medpage Today: Op-Ed: COVID Vaccines Are a Scientific Feat, but 'Prevention' Is a Misnomer

Medpage Today: Op-Ed: Statistical Considerations for Evaluating COVID Vaccine Protection

Medpage Today: Op-Ed: Can Statisticians Save the J&J Vaccine?

Medpage Today: Op-Ed: Why You Should Trust the COVID: Vax

Medpage Today:  Op-Ed: Conceptualizing COVID-19 Vaccine: Hesitancy

News 12 TV Commentary: Man dies after receiving vaccination at Javits Center; doctor says initial indications show no allergic reaction:

News 12 TV: City doctors face vaccine questions involving pregnancy and religious beliefs:

Verywell Health: Communities Step Up to Help Seniors Register for COVID-19 Vaccines:

Speaker (see pages 135-138): FDA Open Public Hearing:  Pfizer-BioTech COVID-19 Vaccine:

Medpage Today:  Considerations for Authorization of Pfizer's COVID Vax:

New York Times: The Greatest Gift to Loved Ones This Covid Winter? Don’t Infect Others

New York Magazine and Vox NewsHow to fight fear and anxiety when quarantine ends

New York Times: Answers to Your Current Coronavirus Questions: Click on the question: How is the winter weather affecting the virus?

MarketWatch: ‘Don’t let COVID fatigue trick you’: How to take care of your physical and mental health this holiday season  

Medpage Today: Why COVID-19 Might Get Worse in Winter, Just Like Flu — Risk and severity of infection, the host and the environment could all play a role

Mercy University FeatureMercy Mavericks (Making a Difference, Fall 2020, p.9)

APA FeatureHow did you get that job? Career Focus Feature in the APA Monitor on Psychology 



  • Ph.D. Health Sciences (International Health, Research and Education):  Touro University, New York          
  • MPH (Master of Public Health): University of the West Indies, Jamaica
  • CStat (Chartered Statistician): The Royal Statistical Society, UK
  • PStat  (Professional Accredited Statistician): The American Statistical Association
  • Fellow of the American College of Epidemiology


Selected Media Appearances and Publications:

Selected Academic Publications

  • Fellow of the American College of Epidemiology

  • CStat (Chartered Statistician): The Royal Statistical Society, UK

  • PStat  (Professional Accredited Statistician): The American Statistical Association

  • Best contributed research paper award (2003) – teaching statistics in the health sciences (The American Statistical Association)

  • I am a founding (Charter) member of the American Statistical Association (ASA) Section on Statistics in Defense and National Security.

  • Diplomate Status: AMHCA (American Mental Health Counselors Association)- Clinical Mental Health Specialist in Substance Abuse and Co-occurring Disorders Counseling

  • Certificate of Recognition - The American Psychiatric Association (APA, 2012)