Although it's just an opinion, I don't think there's any question that Ritalin and other similar drugs are prescribed far too frequently. The PDR writeup, which is the same info that comes in the "handout" you're supposed to get with your prescription, does have some pretty tough warnings about what is needed to diagnose a case where Ritalin is indicated. If the manufacturer's recommendations were followed, there would be virtually NO INDIVIDUAL PRACTITIONERS who could justify the prescription without outside consultation with experts in specialty fields. I suspect that such specialist diagnostic evaluation happens infrequently.
The superficial evaluation that a child may be a potential client for the drug is pretty simple; but confirming that a given child has the specific conditions that will be helped, and eliminating the similar conditions that won't benefit or that may be made worse, requires rather detailed cross checking.
None of the few children I've had direct knowledge of, who have been given Ritalin, ever saw any practitioner other than their "family doctor." Parents involved had no knowledge of what - if any - tests were made to justify the dispensing of the drug to their kids. 'Tain't the way it ought to be, if you believe the manufacturer's instructions.