As far as base choices go, hospitals and clinics are by far the worst, and the rewards, while good, are difficult to use without proper training.
Large numbers of people, including the newly infected, will converge on health-care centers, as will the zombies following them. In fact, a hospital is going to be the most likely source of an outbreak during a Zombie apocalypse scenario as the infected die in the ER and reanimate in the morgue to the surprise of the unfortunate coroners. Infections would spread quickly, hospital staff would be overrun as would feeble patients, many of whom will be left in their beds as the infection spreads, subsequently being devoured and infected themselves, and the facility would quickly be overwhelmed by the undead. If it is at all possible, avoid areas near hospitals, clinics, pharmacies, and nursing homes.
If escape is not possible, it is better to barricade off a wing or floor rather than to hold the entire facility. Stockpiles of food and weapons should be built up and medical supplies should be limited to bandages and painkillers, as attempting to cure or treat zombie bites and scratches would be a futile waste of effort. Additional supplies that may come in handy are plaster mix for broken limbs, splints, and stitching thread. Even though these would serve as long term solutions for serious injuries, it is important to remember that you may need every survivor in your barricade.
- A decent amount of medical supplies, making them great for looting, ambulances should also be looted and can even be used as transport.
- Lots of escape and entry routes, which allow quick getaways should things go bad.
- Wider corridors to facilitiate transport of patients around the facility, which make close quaters combat much easier.
- Back up generators. Should the main power go down electrical equipment should still be able to function, albeit in lower light conditions.
- They also have security systems so if one could make it to the security room, you might be able to use the CCTV cameras to scout out the hospital
- Beds, vending machines and other items found in the hospital can make for an effective barricade. (As seen in the TV series The Walking Dead, and to a lesser extent in the film 28 Days Later)
- Hospitals also have things like bone saws, scalpels, or other improvised weaponry.
- The hospital is the first place where bitten survivors will go during the initial outbreak, this makes them very unsafe as there could potentially be thousands of zombies in there. There may be bandits and raiders, too.
- While most hospitals contain some sort of Café and various vending machines, there is no way to get resupplied once you run out, so you'll need to go looting elsewhere.
- Hard to defend, while having numerous escape routes is an advantage, it also serves as a disadvantage as a zombie or a group of zombies could easily enter through the escape routes.
- Oxygen canisters also present a fire risk. And to top that off, the fire alarm may also attract more zombies.
- Some hospitals are huge, so they may be difficult to clear out and navigate, especially if you've never been to that specific hospital before. If you get lost while being chased by a zombie then you may wind up running into a room with even more zombies.
- While a hospital contains tons of medical supplies, specialized medicines like Inhalers may be short supply, or in no supply at all, unless you can find the pharmacy within the hospital.
- Most hospitals have large glass windows making it easy for zombies or bandits to break in.
- If you choose to stay at a hospital, be careful, as staying too long can have a drastic effect on your mind, which can be even more dangerous especially if you're a loner.