Final answer:
The key principle highlighted is equitable access to healthcare which ensures all residents have access to medically necessary hospital/physician services based on need, not on ability to pay.
Step-by-step explanation:
The key principle highlighted in the statement 'ensures all residents have access to medically necessary hospital/physician services based on need, not on ability to pay' is equitable access to healthcare. This means that everyone should have the same opportunity to receive healthcare services, regardless of their ability to pay. It emphasizes the importance of providing medical care to those in need, rather than prioritizing those who can afford it.
For example, in a healthcare system that ensures equitable access, someone with a serious medical condition would receive the necessary treatment regardless of their financial situation. This principle aims to reduce disparities in healthcare and promote fairness in the distribution of medical services.