Stand-alone or with 'Report'/'Certificate' attached.

In case it is not an exlusive document devoted for estimating the age of an individual, it is then an Age Certificate, i.e. a document issued for the mere purpose of *verifying* existing documents stating the age of the individual. That is why a birth certificate or an affidavit is required upon applying for an Age Cetificate.

Otherwise, with no existing proof/document determining the age of the individual, say in case of crimes or complete absence of documents, a medical report is requested by the authorities to estimate the age of the individual; i.e. Age Estimation.

As far as I understand, an Age Estimation is then attached to an Age Certificate as a proof/verification/official document/etc to be based upon when filling in the birth date entry.