After a petition or a citation has been filed with the court under this subtitle, the court may direct the Department of Juvenile Services or another qualified agency to make a study concerning the child, the child’s family, the child’s environment, and other matters relevant to the disposition of the case. As part of a study under this section, the child or any parent, guardian, or custodian may be examined at a suitable place by a physician, psychiatrist, psychologist, or other professionally qualified person. The report of a study under this section is admissible as evidence at a waiver hearing and at a disposition hearing, but not at an adjudicatory hearing. However, the attorney for each party has the right to inspect the report prior to its presentation to the court, to challenge or impeach its findings and to present appropriate evidence with respect to it.