Medical devices are an integral part of modern healthcare. From stethoscopes to pacemakers, they’ve made dramatic leaps forward in improving health outcomes and revolutionizing healthcare practices.

A medical device is any instrument, tool, machine, or test kit used in the diagnosis, mitigation, treatment, or prevention of disease. It can also be a tool used for direct patient care such as a surgical laser or an X-ray machine.
Diagnosis
An instrument, apparatus, implement, machine, implant, or similar article intended by its manufacturer for use in the diagnosis, prevention, monitoring, treatment, or alleviation of disease or other conditions. Medical devices range from tongue depressors to programmable pacemakers, X-ray equipment, and ultrasound imaging devices.
Manufacturers need to understand how the FDA defines and classifies medical devices to ensure they meet stringent regulatory standards before putting their products on the market. To determine if a product meets the FDA definition of a medical device, manufacturers should consider the intended use and indications for the use of their products. The intended use should describe how the device will directly impact a patient’s health, while indications for use describe the disease or condition that the device will diagnose, treat, cure, mitigate, or prevent.
For example, the OpenFlexure Microscope is used in clinical laboratories to analyze samples of tissues, cells, and bodily fluids for signs of disease or infection. However, because the microscope does not directly interact with patients it falls into the category of laboratory equipment rather than a medical device.
In the EU, medical devices are classified according to their risk and must undergo a formal procedure known as the ‘centralized authorization’ or ‘CE mark’ application process before they can be sold on the market. This includes companion diagnostics, which must also undergo a formal Scientific Advice procedure through the EMA.
Treatment
Medical devices can treat illnesses by stimulating, modulating, or enhancing body functions and anatomic structures. They can also be used to monitor and record health information. Some examples of medical devices include pacemakers and neurostimulators, which can be implanted along the spinal cord to treat chronic pain or in the brain (known as deep brain stimulation) to treat movement disorders such as Parkinson’s disease.
Like drugs, medical devices are heavily regulated due to their direct impact on patient safety. Devices are categorized into three classes according to the level of risk they pose, which is determined by their potential to cause harm or death. Those that are most dangerous receive the highest level of oversight, while low-risk devices require less rigorous testing.
In addition to being regulated by national authorities, medical devices are often governed internationally through agreements like the International Medical Device Regulators Forum (IMDRF). This organization facilitates cooperation and sharing of information between medical device regulators around the world.
Depending on the type of device and the needs of the patient, it may be important for patients to know who manufactures their device. This can help with locating the best available device, or when reporting problems to the Therapeutic Goods Administration in Australia. The agency has an online tool that lists all products and services that have been approved to be sold in the country.
Monitoring
Medical devices monitor, modulate, or supplement anatomical structures and physiological processes such as blood pressure, body temperature, or heart rate. They can be used to identify or exclude diseases and help diagnose and treat medical conditions. They may be used inside the body, such as implanted pacemakers, or outside the body, such as glucose monitoring systems for diabetic patients.
Some medical devices monitor health outcomes such as blood pressure or heart rate, while others are used in laboratory settings to assist with research, experimentation, and analysis. Examples of laboratory equipment include specialized cameras for viewing samples under the microscope and computerized analytical instruments such as chromatographs.
In the United States, all medical devices must undergo a review process before they can be sold to doctors and placed in patients’ hands. Similar to drugs, these medical devices are classified according to their level of risk and the degree of benefit they are expected to provide. Class I devices are those that pose the lowest risk and include common items such as bandages and handheld surgical tools. Class II devices are those that present an intermediate risk, such as X-ray equipment or computed tomography (CT) scanners. Class III devices are those that are of high risk, such as heart pacemakers.
Manufacturers of certain types of high-risk medical devices are required to consult expert panels before submitting a product for approval. These devices are known as ‘borderline’ products and EMA has established a dedicated advice procedure to support them in line with the Medical Devices Regulation.
Assistive Technology
According to the Global Model Regulatory Framework, medical devices are classified into four categories based on their inherent risk. These include Class Ir Devices, which are reusable surgical instruments, and Class IIa devices that are implanted within the body for short-term use such as blood transfusion tubes or catheters. Class III devices, such as pacemakers and neurostimulators (implantable devices that deliver electrical pulses to stimulate or regulate organs), have medium-to-high risk and must meet more stringent requirements including technical files and a conformity test by a Notified Body. In vitro diagnostic products, such as reagents, kits, and analyzers, are also considered medical devices. Likewise, certain radiation-emitting electronic products that have a medical purpose or make medical claims are considered medical devices as well.
Assistive technology is a product, software, or equipment system used to increase the functional capabilities of people with disabilities. It is not intended to replace traditional care. Assistive technology can help improve a person’s quality of life, independence, and safety. It is often necessary for long-term use.
There is a common misconception that any tool or piece of equipment that is used to support a disabled individual in carrying out daily activities qualifies as a medical device. The distinction between medical and assistive technology is vital to the effectiveness of this type of equipment. For example, the use of hoists and slings that are poorly maintained or used incorrectly can lead to injuries, which has led to joint messages from MHRA the Health & Safety Executive, and the National Patient Safety Agency on this issue. In contrast, laboratory equipment such as an incubator that maintains precise environmental conditions for cell culture in a research setting is not a medical device because it does not have a direct impact on patients.