| Types of studies | Non-English language. |
| Published pre-1990. |
| Grey literature or not published in a peer reviewed journal. |
| Dissertations or theses. |
| Proceedings. |
| Commentary articles, written to convey opinion or stimulate research and/or discussion, with no research component. |
| Types of participants | Non-medical healthcare professional, allied healthcare professionals only. |
| Dentists, dental practitioners, vets, nurses, medical students. |
| Types of outcome measures | Anything except doctors’ perspective. |
| Switching between specialties. |
| Burden on patients, societal perspectives. |
| Economic burden at a society level; for example, costs to government or councils. |