examens médicaux

Bonjour,
J’ai fait ma demande de visa. J’ai recu un mail de confirmation, je pense (puisque j’ai eu le numéro de visa et la phrase « you have been granted a wvh… »!
Ceci dit, avant de recvoir ce mail, j’ai recu ceci :
You should read this information carefully before contacting the
Department.

If you have been requested to complete health examinations, you should
attend your appointment within 28 days after the date of notification. If
you are unable to complete your health examinations within this period,
you must contact the Working Holiday Visa Processing Centre and provide
reasons as to why you are unable to do so. If you do not attend your
health examinations or contact the department within 28 days after the
date of this notification, a decision may be made on your visa application
based on the information held by the department.

Est-ce que ca sous-entend qu’une visite médicale chez un médecin de la liste est obligatoire ? Est-ce qu’on peut nous demander ce genre de justificatifs à l’entrée sur le territoire ?
Un grand merci!
Cécile