What are health or medical instruments used in treatment, diagnosis, or prevention of diseases known as?

Health or medical instruments employed in the treatment, diagnosis, or prevention of diseases are classified as medical devices. This category encompasses a broad range of products that are essential in various aspects of healthcare, including equipment like MRI machines, pacemakers, surgical instruments, and even diagnostic tools such as blood glucose monitors.

Medical devices are characterized by their intended use, which is to aid healthcare providers and patients in effectively managing health conditions. They can vary significantly in complexity, from simple items like thermometers to highly sophisticated systems such as robotic surgical apparatus.

The other options refer to more specific types of tools or devices. Assistive devices are typically meant to help individuals with disabilities perform daily tasks, interventive devices commonly relate to specific procedures or interventions, and surgical devices are explicitly designed for use during surgical operations. While all these options fall under the broader category of medical devices, the term "medical devices" is the most accurate choice when considering the full spectrum of instruments used in healthcare.