administration appalachianregion clinicalcompetence culturaldiversity distribution drugtherapy ethics healthcaredisparities healthservicesaccessibility mentaldisorders moralandethicalaspects nervoussystemdiseases organization pharmaceuticalpreparations qualityofhealthcare ruralhealth ruralhealthservices socioeconomicfactors standards substance-relateddisorders supply therapy unitedstates w76aa6 wa390e842008 wm400 wm402