Bruce Ackman Alexey, I'd like more context to your question. As product developers, we try our best to design in effectiveness. This is done by developing a product specification and then designing and engineering each specification and relying on verification and validation (through user testing) to ensure that the specifications are met. Regulatory agencies then ensure that claims regarding efficacy are valid. More information please....

Alexey A. Kudryashov Bruce, I probably have not correctly identified the problem.
We are talking about operational efficiency.
What the machine can produce therapeutic procedures, diagnostic tests, etc., and what actions will be held the staff actually.
This is a rough estimate, because there are many indirect factors, such as clinics profile, the regional flow of patients, teaching and learning of personnel, etc.

This is a great question. The FDA human factors guidelines call for safe, effective and efficient devices. There is guidance on what safe and effective means. These are the two major concerns. I have not found guidance on what 'efficient' operations means to the FDA. I test based upon the general definition of efficient, does the device perform the job using steps that make sense and do it in timely fashion? or, are there extra unnecessary steps. That is a concern for users of medical systems since time is in short supply.

According to the World Health Organization in Geneva, "a device is clinically effective when it produces the effect intended by the manufacturer relative to the medical conditions. For example, if a device is intended for pain relief, one expects the device to actually relieve pain and would also expect the manufacturer to possess objective evidence, such as clinical test results, that the device does in fact relieve pain. Effectiveness can be thought of as efficacy in the real world clinical environment." You also need to consider technical and safety requirements of the device.

Alexey A. Kudryashov Jose, colonoscope in a psychiatric hospital should have zero effectiveness. The machine must be where it is needed. Effective not only in quality but also in use.
The car must go!