Is it a certainty that service quality only affects which facility the citizen will choose, and has no effect on the quality of the care itself? In other words, if both clinic and hospital visits max out the health meter, does the person who visited the clinic see their health meter shrink more rapidly than those who visit a hospital? With the other variables involved, it may be hard to quantify.

As for Gerontology, it has it's place in challenges that require a large population. If you have some facilities set to make babies, and some set to keep old folks ticking, populations will grow faster than without the gerontology, from my observations.