A medical certificate, under normal situations, should mention the expected period of absence from duty necessitated because of the disease of the patient. Due consideration should be given to the circumstances prior to issuing a certificate that certifies a period of illness in back date, especially in case of a patient with a minor short illness, which is not seen on the date of examination. Supplementary remarks must be added, where appropriate, to explain the circumstances that warranted the issuance of a retrospective certificate. The medical certificate must also carry the signature or thumb impression of the patient. (DMC/647/2010)