Dear Ramiz G
it is only a matter of getting a print and signing by a duty doctor of a public sector hospital. I am suggesting this coz preventive officer/ appraising & valuation/inspector customs are alike jobs & same requirements were published for all jobs i.e height of 5' 6" and chest 33".
For preventive they asked aspirant to furnish this certificate , thats why in my opinion it is better to provide.
who knows they might reject the candidature during pre selection and one would have to file review application before Fpsc to prove that they have asked for this at the time of doc's required afterall it is pakistan. . that is why a stitch in time saves 9