I know a few people in the Barkley camp and others who think hes FOS when it comes to his research on the incremental validity of a NP evaluation. My opinion is that his conclusion is off base and not entirely logical. This is after taking a course on ADHD assessment by someone who LOVES Barkley. I've assessed a lot of kids on meds who have been given a diagnosis of ADHD, only to find that they have a learning disorder or something else that explains both why they suck at school and why the meds arent working. What sucks is that the evals come 1-2 years after the ADHD Dx and they are a lot more behind in school than they should be even with the LD. To me, ADHD is a disorder of comorbidity, so I will always want to test. As far as parent rating scales go, you can use them as long as you know that many things other than ADHD will drive up those scales.
To be fair, I havent seen those kids who see a physician, get a prescription without being referred for testing, and its working for them. I really have no problem with that in a case where the parents and teachers are completely miserable and there is no evidence for something else going on. I just assume that the physician is aware of the comorbidity rates and developmental trajectory of things that look like ADHD but are not, especially in younger kids. Just like I assume that when someone gives an MMSE, they know that a score of 28 and no evidence of decline from collateral does not mean that the patient does not have dementia b/c its sensitivity to mesial-temporal functioning is questionable.
Btw, there is someone better than Barkley...James Hale. Here are a few citations for those who care:
Hale, J. B., Reddy, L. A., Semrud-Clikeman, M., Hain, L., Whitaker, J., Morley, J., Lawrence, K., Smith, A., & Jones, N. (in press). Executive impairment determines ADHD medication response: Implications for academic achievement. Journal of Learning Disabilities.
Hale, J. B., Reddy, L. A., Wilcox, G., McLaughlin, A., Hain, L., Stern, A., Henzel, J., & Eusebio, E. (2009). Assessment and intervention for children with ADHD and other frontal-striatal circuit disorders. In D. C. Miller (Ed.), Best practices in school neuropsychology: Guidelines for effective practice, assessment and evidence-based interventions (pp. 225-279). Hoboken, NJ: John Wiley & Sons.
Hale, J. B., Reddy, L. A., Decker, S. L.,Thompson, R., Henzel, J., Teodori, A., Forrest, E., Eusebio, E., Denckla, M. B. (2009). Development and validation of an executive function and behavior rating screening battery sensitive to ADHD. Journal of Clinical and Experimental Neuropsychology, 31, 897-912.