Section 67G. Every person in control of a child who has reached age four shall cause such child to be given a complete pure tone test using conventional audiometric tests at such public schools and by such pediatric audiologists or school testers as are approved and designated by the commissioner. The costs for such examinations shall be borne by the commonwealth. In the event such a child fails such pure tone tests, the tester or pediatric audiologist shall advise the parent or legal guardian to consult the otologist of his choice who is in private practice. If upon examination such otologist recommends further tests, the diagnostic services of the approved hospital centers referred to in section sixty-seven F shall be made available to such children at a cost to be borne by the commonwealth.