Health Reference Center Academic
This is a very large database of over 9.5 million references. It covers all health issues including illnesses, chronic illnesses, healthcare reforms, fitness, professional standards and evaluation. It is important to note that these are covered from the health professional and academic perspective rather than a consumer perspective. It is nonetheless a very useful source of information for any work you have which touches on these areas.
In addition the Gale databases at my.lawsociety.org.nz also have two more databases that cover parts of this area – Nursing and Allied Health Collection and a more public oriented Health and Wellness Resource Center & Alternative Health Module.
All of them are worth a look.