A medical certificate is a legal document and doctors can be prosecuted for writing untrue information. Certificates can only be issued for genuine illness.

Wherever possible, please make an appointment for the day you feel too sick to work. Certificates must be dated on the day they were written or they are invalid.

Details of your illness are confidential and do not need to be written on the certificate, unless required by law, such as for worker's compensation. Employers should not expect a diagnosis, except in special circumstances.