Internal Medicine vs. Family Medicine

There are fundamental differences in the focus, training, and patient care activities of the two specialties of internal medicine and family medicine.

Historically, the two specialties developed from very different backgrounds. Internal medicine grew out of the increasing application of scientific knowledge into the practice of medicine starting in the late 1800s. This “scientific” approach to medicine was unique at the time and was progressively applied to the wide spectrum of diseases that commonly affect adults. With the growth and development of pediatrics as a separate specialty devoted to the care of children in the early 1900s, internal medicine continued its primary focus on adult patients. 

The specialty of family medicine grew out of the general practitioner movement in the late 1960s in response to the growing level of specialization in medicine that was seen as increasingly threatening to the primacy of the doctor-patient relationship and continuity of care. Conceptually, family medicine is built around a social unit (the family) as opposed to either a specific patient population (i.e. adults, children, or women), organ system (i.e., otolaryngology or urology), or nature of an intervention (i.e., surgery). Consequently, family physicians are trained with the intent to be able to deal with the entire spectrum of medical issues that might be encountered by the members of a family unit. 

Much of the confusion likely arises because the majority of patients seen by family physicians are adults, thus overlapping with the patient population focused on by internal medicine physicians. A general estimate is that a typical family medicine practice might see 10% to 15% children, meaning that 85% to 90% of patients will be adults, the same population seen by internal medicine physicians. Additionally, an increasing number of family physicians do not include obstetrics, neonatology, or significant surgery as part of their practices, which makes the care provided to adults appear similar to that provided by internal medicine physicians. These factors make it is easy to see that the differences between general internal medicine and family medicine may not be easily understood.

However, there are significant differences in the training and clinical approach of internal medicine physicians and family physicians1,2. Although the length of basic training for both is three years, internal medicine focuses only on adults (internal medicine physicians who wish to include the care of children in their practice may choose dual training in internal medicine and pediatrics, frequently referred to as “med-peds”; you can find out more about this career path). Required internal medicine training centers on common general medical conditions, but also includes significant experience in each of the internal medicine subspecialties (such as endocrinology, rheumatology, and infectious diseases) and neurology. Trainees must also gain adequate experience in psychiatry, dermatology, ophthalmology, office gynecology, otorhinolaryngology, non-operative orthopedics, palliative medicine, sleep medicine, geriatrics, and rehabilitation medicine to comprehensively care for adults. Internal medicine training must also take place in both outpatient and inpatient settings. All trainees are required to have a longitudinal outpatient continuity clinic experience in which residents develop continuous, long-term therapeutic relationships with a panel of general medicine patients. In addition to this continuity clinic experience, trainees also see outpatients during the course of their subspecialty clinical rotations. At least one year of internal medicine training must involve caring for hospitalized patients, with at least three months of work in intensive/critical care settings. Most training programs require more than one year of hospital-based work with additional training on inpatient subspecialty services such as cardiology, hematology-oncology, or gastroenterology.  

Family medicine training is typically based in dedicated outpatient training centers in which residents work throughout the course of their training. Trainees are required to provide acute, chronic, and wellness care for a panel of continuity patients, with a minimum number of encounters being with children and older adults. Family medicine trainees are also required to have at least 6 months of inpatient hospital experience and 1 month of adult critical care, and up to 2 months of care for children in the hospital or emergency settings. Additional requirements include 2 months of obstetrics, a minimum number of newborn encounters, 1 month of gynecology, 1 month of surgery, 1 month of geriatric care, and 2 months of training in musculoskeletal medicine. Family medicine trainees must also have experiences in behavioral health issues, common skin diseases, population health, and health system management, and there is a particular emphasis on wellness and disease prevention.

These differences between internal medicine and family medicine training result in unique skill sets for each discipline and different strengths in caring for patients. Because internal medicine education focuses only on adults and includes experience in both general medicine and the internal medicine subspecialties, training in adult medical issues is comprehensive and deep. The general and subspecialty nature of training equips internal medicine physicians to develop expertise in diagnosing the wide variety of diseases that commonly affect adults and in managing complex medical situations where multiple conditions may affect a single individual. internal medicine physicians are well prepared to provide primary care to adults through their outpatient continuity experience during training, particularly for medically complicated patients. Their training also enables them to effectively interact with their internal medicine subspecialty colleagues in co-managing complex patients (such as those with transplants, cancer, or autoimmune disease) and easily managing the transitions from outpatient to inpatient settings (and vice versa) for their patients who require hospitalization. Additionally, the extensive hospital experience during training uniquely prepares internal medicine physicians who choose to focus their clinical work in inpatient settings (learn more about hospital medicine).

Family medicine education is broader in nature than internal medicine since it involves training in the care of children and procedures and services often provided by other specialties. This breadth of education equips family physicians to deal with a wide range of medical issues, and this broad skill set may be particularly valuable in communities or geographical areas where certain specialists and subspecialists may not be available. Because of their broad skill set, family physicians typically adapt the nature of their practices to meet the specific medical needs of their community. Although the depth of training in adult medical issues may be less than in internal medicine, the emphasis on outpatient medicine, continuity of care, health maintenance, and disease prevention allows family physicians to function as primary care physicians for adults as part of a family unit depending on individual medical need. And family physicians are trained to coordinate care among different specialists and subspecialists when these services are needed by their patients. 

Thus, it can be seen that there are important differences between internal medicine and family medicine.  Both have unique skill sets and important roles in the care of adult patients and providing primary care depending on the practice setting and the specific needs of the patient.

1Accreditation Council on Graduate Medical Education (ACGME) Revised Common Program Requirements for Internal Medicine, July 1, 2016 (Accessible at:

2Accreditation Council on Graduate Medical Education (ACGME) Revised Common Program Requirements for Family Medicine, July 1, 2016  (Accessible at:

Other topics you may find interesting

About Internal Medicine

What's an internal medicine physician? Where do they practice? Who do they treat? 

Learn More

Internal Medicine Subspecialties

internal medicine physicians can focus on general internal medicine or take training to "subspecialize" in additional areas of internal medicine.

Learn More

The History of Internal Medicine

Learn the origins, rich history, and the specific features that make internal medicine such an important part of medicine today.

Learn More