the photoraphy apart, for which you will get training, you will need to show normal communication skills such as kindness, small talk, sympathy, ability to deal with all age groups, especially elderly. They are especially keen on how you get on with minority groups, gays, ethnic groups, maybe not able to speak english, learning difficulties. Can you give one or two an examples of where you have helped one of these groups in a difficult situation. How did you resolve it. The list goes on! They like teamwork. What do you do outside work, any clubs, team sports, cub leader, anything like that. Even visiting old people. You will think of something so that you can answer so that it does not sound as if you are making it up. Reading,driving, painting, socializing, holidays abroad are out! Might help if you can show some knowledge of diabetes/retinopathy.
good luck