看了链接,个人感觉这只是说明《出生医学证明》具有法律效力的重要医学文书。同时说明了1996年1月1日前出生的公民,如需出生证明,以“出生公证书”为合法有效文件。出生公证书并不意味着就是做《出生医学证明》的公证,不过如果公证了《出生医学证明》同样应该有法律效应。
看看官网上关于年龄的要求:
Evidence to attach to your application
You must attach a certified copy of a full birth certificate for you and each secondary applicant included in your application.
If birth certificates are not available in your country of birth, other evidence to confirm birth details include, but are not limited to:
school records
passport
baptism certificate
family book showing date of birth
ID document issued by your government
hospital birth records
court documents that verify your date of birth
copies of military service records or discharge papers.
Proof of age must be included to make your application complete.