You don't just want to say that you're an expert or have a lot of experience, but be a little bold here by stating that, although you find it very impressive here, you have noticed that there are some gaps in the total picture of care rendered, and you feel you can fill these gaps. This is a way of saying that selecting you will not only get what it needs, but even exceed it. You can further state that you can bring this hospital or group additional resources that most hospitals don't have, which would make this organization stand out above the rest. (These are the offerings that will make you particularly attractive, where you tout your special interests). Special interests are specific aspects of one's specialization that do not have the bureaucratic designation of certification by a board. For example, you may be board certified or board eligible in Family Medicine, or even further trained (for example, in Hospital and Palliative medicine), but you might say you have a special interest in geriatric medicine. This would sound very fortuitous to a hospital struggling with a high geriatric co-morbidity rate in its demographic.