The NZ Medical Association has advised their members the following in respect of the issuing of retrospective medical certificates.
- Issuing a retrospective medical certificate is inadvisable and should be done only if the doctor can be confident that the illness commenced at the time stated on the certificate. The date when the certificate is issued should be clearly stated (i.e. not just the date of the illness), and should always be the date on which the patient is seen.
- A doctor may be confident of such an earlier commencement of the disease, if the signs and symptoms and state of the disease process indicate that the disease would be of a duration which is consistent with an earlier nominated date.
- The medical certificate should indicate the evidence on which the certificate is based, i.e. the doctor's examination or the patient's statement.
- In situations where the patient presents fully recovered asking for a certificate to cover a recent minor illness, the doctor should either decline to give such a certificate or make it clear that the certificate is based solely on the patient's uncorroborated history.
- Under no circumstances must a doctor give a certificate which implies observations which were not made or an examination which did not occur.