Several definitions of telemedicine were advanced both in print and in everyday usage. Jeffrey Bauer and Marc Ringel found that no single meaning was clearly dominant.¹ Listed below are a few of the typical definitions that illustrate the field's meaning over the past few years. They are arranged by Bauer in sequence by year of publications to demonstrate the expansion of telemedicine. In addition, the definitions of telehealth and telenursing as prepared by the American Nurses Association are included below.

Telemedicine is:
...a system of healthcare delivery in which physicians examine distant patients through the use of telecommunications technology. ²
...the use of telecommunications for medical diagnosis and patient care. ³
...the use of telecommunications and information technology to provide healthcare services to persons who are at some distance from the provider. ⁴
...new uses of information and technologies that are emerging, as well as the ability to move the caregiver and information to where the patient is rather than moving the patient to centralized places to deliver health services and information. Today's telemedicine model is evolving to "teleconsultation," where a physician consults with other specialists or a patient, using high-quality video-conferencing, with that consultation enabled by online information access. ⁵
...remote communication of information to facilitate clinical care and includes voice, images, elements of a medical record, and commands to a surgical robot. ⁶
...the use of telecommunications technology, including satellite links, dedicated line connections, interactive television systems and Internet connections, to provide healthcare services to patients at some location separate from the provider. ⁷
...a composite term for health-related activities, services, and systems, carried out over a distance by means of information and communications technologies, for the purpose of global health promotion, disease control and healthcare, as well as education, management, and research for health. ⁸

Defining Telemedicine for the Future:
Bauer and Ringel state that the above definitions are somewhat static and do not capture the accelerating dynamism of the interface between communications, computers, information, and healthcare. They state emphatically that telemedicine will be the great equalizer, forging new relationships between patients and all types of practitioners, and attaining true consumer empowerment.

The historical definitions fail to incorporate related changes that are taking place in other dimensions of healthcare delivery. For example, most attempts to explain telemedicine are cast either explicitly or implicitly in the context of a doctor-patient relationship. This physician-centric perspective misses one of the most significant long-term effects of the telemedicine revolution-the expanding clinical powers of nonphysician practitioners and of patients who will use telemedicine to access a knowledge base that has been controlled by medical doctors. ⁹

The 21st century model of healthcare will see patients make decisions with assistance from a variety of practitioners (including physicians) and electronic decision-support tools. This empowerment of consumers is perhaps the most dramatic change that will be propelled by the revolution in healthcare communications. The futuristic definition prepared by Bauer and Ringel, below, places telemedicine in its proper perspective as one of the most powerful forces shaping a new, different, and better health system for the twenty-first century:

"Telemedicine is the combined use of telecommunications and computer technologies to improve the efficiency and effectiveness of healthcare services by liberating caregivers from traditional constraints of place and time and by empowering consumers to make informed choices in a competitive marketplace." ¹⁰

Tele-Definitions From the American Nurses Association:
Published by the ANA in 1997, Telehealth: A Tool for Nursing Practice,¹¹ the document offers the following definitions as an initial glossary of terms used in discussing telehealth:

Telecommunications refers to the transmission, emission or reception of data or information, in the form of signs, signals, writings, images and sounds or any other form, via wire, radio, visual or other electromagnetic systems.

Telehealth is the removal of time and distance barriers for the delivery of health care services or related health care activities. Some of the technologies used in telehealth include: telephones, computers, interactive video transmissions, direct links to health care instruments, transmission of images and teleconferencing by telephone or video.

Telenursing is a subset of telehealth in which the focus is on nursing practice via telecommunications.

Telemedicine, similarly, is another telehealth subset. Telemedicine includes many medical specialties, such as teleradiology, teledermatology, telepsychiatry, etc.

Earlier, in 1996, the ANA published Telehealth - Issues for Nursing¹² which contains the following statement: "ANA strongly believes that the strength of telehealth lies in providing increased access to health care services by augmenting existing services, not in replacing them. Telehealth technologies should not be used to replace needed access to in-person health care services."

And, finally, from the ICN:

Telenursing Definition from International Council of Nursing:  Succinct, simple definition.

"Telenursing refers to the use of telecommunications technology in nursing to enhance patient care.  It involves the use of electromagnetic channels (e.g. wire, radio and optical) to transmit voice, data and video communications signals.  It is also defined as distance communications, using electrical or optical transmissions, between humans and/or computers."¹³

References:

¹ Bauer, Jeffrey and Ringel, Marc. Telemedicine and the Reinvention of Healthcare: The Seventh Revolution in Medicine. New York: McGraw-Hill, 1999.

² Preston, Jane. (1993) The Telemedicine Handbook: Improving Health Care with Interactive Video . Austin, TX: Telemedical Interactive Consultative Services, Inc., p. 1. (Dr. Preston was founding president of the American Telemedicine Association.)

³ Lindbergh, Donald (Director, National Library of Medicine) in testimony to the US House of Representatives, Committee on Science, Space, and Technology; Subcommittee on Oversight and Investigations, May 2, 1994.

⁴ Grigsby, J., Schlenker, RN, Kaehny, MM, Shauygnessy, PW, Sandberg, EJ. Analytic Framework for Evaluation of Telemedicine. Telemedicine Journal, 1: 31-39, 1995.

⁵ US Department of Commerce, National Telecommunications and Information Administration. A Nation of Opportunity: Realizing the Promise of the Information Superhighway. US Government Printing Office, 1996.

⁶ Coiera, E. Guide to Medical Informatics, the Internet, and Telemedicine. New York: Chapman and Hall Medical, 1997. As quoted in Journal of American Medical Association, 280 (15): 1367, October 21, 1998.

7. A Glossary of Health Care Terms, 3rd Ed. Boston, MA: Gouston & Storrs, 1997.

⁸ World Health Association. A Health Telematics Policy: Report of WHO Group Consultation on Health Telematics. Geneva, Switzerland: December 11-16, 1997.

⁹ Bauer, J. and Ringel, M., op.cit., p.8.

¹⁰ Bauer, J. and Ringel, M., op.cit., p 4. (For a detailed analysis of expanding independence of nonphysician clinicians, see Jeffrey C. Bauer, Not What the Doctor Ordered: How to End the Medical Monopoly in Pursuit of Managed Care. New York: McGraw-Hill, 1998.)

¹¹ American Nurses Association. (1997) Telehealth: A Tool for Nursing Practice. In Nursing Trends & Issues, ANA Policy Series. Washington, DC: ANA.

¹² American Nurses Association. (1996) Telehealth: Issues for Nursing. In Nursing Trends & Issues, ANA Policy Series. Washington, DC: ANA.

¹³ International Council of Nursing (ICN).  Telenursing.  Accessed June 12, 2006.