Key points are not available for this paper at this time.
Overall scores on the OSCE are often not very reliable. It is more difficult to reliably assess communication skills than clinical skills when considering both as general traits that should apply across situations. It is generally helpful to use two examiners and large numbers of stations, but some OSCEs appear more reliable than others for reasons that are not yet fully understood.
Brannick et al. (Tue,) studied this question.