Research made by Fielding and Evered in 1977 compared how doctors reacted to different accents. They used RP and a regional accent in the study. As a conclusion they found out that people who spoke RP were not taken as seriously as people who spoke a regional accent. That is, doctors thought that RP spekears merely imagined their condition of being actually ill, whereas regional accent speakers were taken more seriously and they were actually ill, at least, in doctor's opinion.
How current is this study nowadays? As a non-native English speaker I find this plainly dreadful.