Objective Structured Clinical Examination - OSCE Marking

OSCE Marking

Marking in OSCEs is done by the examiner. Occasionally written stations, for example, writing a prescription chart, are used and these are marked like written examinations, again usually using a standardised mark sheet. One of the ways an OSCE is made objective is by having a detailed mark scheme and standard set of questions. For example, a station concerning the demonstration to a simulated patient on how to use a Metered dose inhaler would award points for specific actions which are performed safely and accurately. The examiner can often vary the marks depending on how well the candidate performed the step. At the end of the mark sheet, the examiner often has a small number of marks that they can use to weight the station depending on performance and if a simulated patient is used, then they are often asked to add marks depending on the candidates approach. At the end, the examiner is often asked to give a "global score". This is usually used as a subjective score based on the candidates overall performance, not taking into account how many marks the candidate scored. The examiner is usually asked to rate the candidate as pass/borderline/fail or sometimes as excellent/good/pass/borderline/fail. This is then used to determine the individual pass mark for the station.

Many centers allocate each station an individual pass mark. The sum of the pass marks of all the stations determines the overall pass mark for the OSCE. Many centers also impose a minimum number of stations required to pass which ensures that a consistently poor performance is not compensated by a good performance on a small number of stations.

There are, however, criticisms that the OSCE stations can never be truly standardised and objective in the same way as a written exam. It has been known for different patients / actors to afford more assistance, and for different marking criteria to be applied. Finally, it is not uncommon at certain institutions for members of teaching staff be known to students (and vice versa) as the examiner. This familiarity does not necessarily affect the integrity of the examination process, although there is a deviation from anonymous marking. However, in OSCEs that use several circuits of the same stations the marking is repeatedly shown to be very consistent which supports the validity that the OSCE is a fair clinical examination.