| Name | Info | Provider | Link |
|---|---|---|---|
| subscription/membership/fee required | Elsevier Science | https://linkinghub.elsevier.com/retrieve/pii/00006396-201104000-00028 | |
| Choosing a Doctor or Health Care Service | free resource | MedlinePlus Health Information | https://medlineplus.gov/choosingadoctororhealthcareservice.html |
| subscription/membership/fee required | Ovid Technologies, Inc. | http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=21295404.ui | |
| subscription/membership/fee required | Wolters Kluwer | https://doi.org/10.1016/j.pain.2011.01.002 |