The Supreme Court & many High Court of states have ruled that report of ossification is the expert opinion & not conclusive. Ossification test can assess the age but there will be error of plus or minus 2 years.
The Certificate of Birth issued by the village or municipal authority is conclusive evidence of age. Expert evidence or the Ossification report can be considered only If the authentic or conclusive evidence is not available.
School Leaving Certificate is also considered if the Birth Certificate is not available.