She joined the University of California, Berkeley for graduate studies, where she worked toward a master's then doctorate in public health.
[citation needed] She studied dependencies on tobacco and alcohol, the availability of breast and cervical cancer screening and the improvement of access to palliative care.
D'Onofrio led the United States' first randomized controlled trial on preventing young people from smoking or chewing tobacco.
This observation motivated D'Onofrio to launch Breast Health Access for Women with Disabilities, an initiative that became a national model.
[4] Working with Rosalind Singer, D'Onofrio called out school textbook authors for featuring sugary snacks as rewards for good behavior.