See now, where would you place phone screening for clinical research? It involves taking medical histories for people and documenting the background of their conditions.. I can't smell them, but I'd still consider it patient interaction comparable to what I've done at any hospital or clinic.
Hmmm... is it research and the people are potential research subjects. Are they really patients or are you just recruiting people with medical histories for research purposes? Do you have a phone script or do you have to think of the questions you should ask them on your own, on the fly?
Are you paid to do this? If so, I'd just call it employment and describe what you did on the job.
If this is volunteer, I'd call it non-clinical because it is telephone surveying just as if you were doing opinion polls or canvasing for political candidates. Not to say you don't learn something from it but it is not the same as smelling patients.
I had surgery for a broken bone. I could not have found my way from my hospital room to the front door on my own and I would have found it difficult to push the wheelchair myself and impossible to find a chair to climb into if one hadn't been brought to me. The volunteer who brought the chair and pushed it to the exit was doing a very necessary job and one that made it possible for the nursing assistants to remain on the ward with the patients who needed their skills. Don't brush off what volunteers do as unimportant.
Looking after people's need for food, clothing, recreation (such as being a scout leader or sports coach), a safe place to live, and academic skills such as reading, writing and math are non-clinical. Working in the emergency department, translating for health care workers, serving on an ambulance or as an emergency responder, assisting with physical or occupational therapy, feeding, turning, bathing and transferring the disabled in a health care facility, transporting patients, directing patients and families from an information desk, providing comfort and messages to waiting family in a surgical waiting room -- all would be clinical, IMHO.
Gray zone: playing music for nursing home residents, recreation with people with disabilities.