In late August, the International Baccalaureate (IB) became aware that a mark scheme associated with a history question paper contained plagiarised material (“IB lifted exam marking guides from Wikipedia”, October 8). A mark scheme is the guide provided to examiners on how to award marks to students’ answers.

This is a serious issue and was in contravention of IB policy. Our quality assurance process was insufficient on this occasion. The IB is still investigating the matter and deeply regrets that this has occurred. No student or examination results have been affected by this issue. The question paper was original and reliable.

Our instructions to question paper authors have always contained rules on the use of source material and we are reinforcing these instructions at all future paper editing meetings. We are reviewing both our examiner contract documentation and our quality assurance processes, which we do as a matter of course as part of best organisational practice.

Academic rigour and honesty have been cornerstones of the IB since it was founded. We have and always will take immediate and appropriate action when we discover any violation of our policies or standards.

Judith Fabian, Chief academic officer, International Baccalaureate, Cardiff.