Internal and Family Medicine
Dr. Stephen Sisselman is Board Certified in Internal Medicine, and Dr. Jill Sisselman is Board Certified in Family Medicine. They care for patients ages 12 and up, and their care encompasses Adolescents and Women's Health as well. They provide the latest technology and compassionate care. With offices in both Massapequa and Commack, our offices are sure to be convenient to both you and your family.
Clinical Lipidology
Dr. Stephen Sisselman is also a Board Certified Lipidologist. This means that he has additional specialized training in high-risk disorders such as the Metabolic Syndrome, Obesity, Dyslipidemia and Diabetes.
PCMH - Patient Centered Medical Home
The National Committee for Quality Assurance (NCQA) announced that Sisselman Medical Group has received recognition from the NCQA Patient-Centered Medical Home program for using evidence-based, patient-centered processes that focus on highly coordinated care and long-term relationships. Sisselman Medical Group has successfully rectified their level 3 PCMH status in 2017 and 2019.
The patient-centered medical home is a model of care emphasizing care coordination and communication to transform primary care into what patients want it to be. Research shows that medical homes can lead to higher quality and lower costs, and can improve patients' and providers' reported experiences of care. The NCQA PCMH Recognition program identifies practices that promote partnerships between individual patients and their personal clinicians, rather than treating patient care as the sum of episodic office visits. Each patient's care is delivered by clinician-led care teams that provide all health care needs and coordinate treatments across the health care system. Medical home clinicians demonstrate the benchmarks of patient-centered care, including open scheduling, expanded hours and appropriate use of proven health information systems.
Patient Survey
At Sisselman Medical Group we try to improve the quality of care we deliver.
Please complete this short 5 minute survey so we can accomplish our goals of being the Ultimate Center for Primary Care Medicine on Long Island.
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The Sisselman Medical Group Family!

Dr. Stephen Sisselman
PhysicianDr. Stephen Sisselman received his undergraduate degree from Tufts University, in Massachusetts. He then attended Medical School at the New York College of Osteopathic Medicine. After finishing Internship at Massapequa General Hospital, he completed a Residency in Internal Medicine at Christiana Hospital, in Newark, Delaware. In private practice since the year 2000, Dr. Sisselman is dedicated to providing exceptional medical care in a warm, compassionate environment.
Dr. Jill Sisselman
PhysicianDr. Jill Sisselman graduated from SUNY Albany and then received her Medical degree at the New York College of Osteopathic Medicine. After Internship at Massapequa General Hospital, she completed Residency at St. Francis Hospital in Delaware. She is Board Certified in Family Medicine. Dr. Sisselman provides a "Family Friendly" approach to her practice, and provides services in Teen and Adolescent Care, Women's Health, Premenstrual Disorders and Menopause. She also provides outstanding care in General Family Medicine.
Sabrina MacKittrick, NP-C
Nurse PractitionerSabrina MacKittrick graduated from the University of Scranton in 1994 with a Bachelor of Science in Human Services. Sabrina worked as drug and alcohol counselor for AIDs patients as well as a project coordinator for the Home Care division of the New York City Health and Hospitals Corporation prior to becoming a registered nurse. In 2006 Sabrina graduated from SUNY Downstate School of Nursing with a Bachelor of Science in nursing, and was an RN at Bellevue Hospital Center in Manhattan where she honed her skills in the Emergency Department. While working there, Sabrina earned her Masters of Science in Nursing to become a Nurse Practitioner. Her specialty is Adult-Gerontological Nursing. Sabrina has a passion for primary care. Sabrina understands the importance of empowering patients about their health and wellness, and encourages a holistic approach to maintaining a healthy lifestyle.
Lauren Iarrobino, NP-C
Nurse PractitionerLauren graduated from University of Delaware in 2005 receiving her Registered Nurse license. She practiced in the medical/surgical areas in the hospital setting and then many years with oncology patients in Huntington Hospital. In 2013, from Molloy College she received her Masters of Science in Nursing in Adult Health as a Nurse Practitioner. Lauren has a passion for primary care, patient centered care and working together with patients to optimize health, wellness, and overall patient well-being. She also strives to help empower patients through patient education and preventative care.
Amy Roberts, PA-C
Physician AssistantAmy graduated from the Physician Assistant Program at Hofstra University and received the Clinical Excellence Award. Her practice focus is in Internal and Family Medicine. She has an extensive background in Radiology, and had been a Radiological Technologist prior to becoming a P.A. She strives to make a positive impact in the healthcare field. Amy is caring and compassionate and her patients always come first. She is an excellent addition to our team.
Elizabeth Westendorf, PA-C
Physician AssistantElizabeth received her undergraduate degree from the College of St. Scholastica in Duluth, MN. She then attended Mercy College in NY to receive her Masters of Physician Assistant Studies. Her practice focus is in Family and Internal Medicine. Dedicated to several PA initiatives that advocate for the patient's right to greater access of healthcare resources and greater quality of care, as well as promoting wellness throughout all age groups.
Erin Alt, PA-C
Physician AssistantErin Alt graduated from Touro College with a Bachelor of Science in Physician Assistant Studies in 2003. She has worked in Primary Care for the past fifteen years, and has a true passion for ensuring that her patients receive compassionate and quality care. She is a strong advocate of preventative medicine and patient education.