I'm not quite sure where the 25% misdiagnosis rate attributed to MJFF comes from. I've not heard/seen that number but yes, the number is high.

I'm more familiar with this stat: 15% to 18% of subjects enrolled in PD trials are later found not to have PD. This reflects two things...just how hard PD is to diagnose--particularly in the early stages of disease even by specialists (since they are the ones referring/recruiting "patients" into trials). And, we assume away from specialists and the clinical research setting, the numbers are higher.

This is devastating for patients/families who are looking for answers. It can have a negative effect on optimizing treatment and it means that we are testing therapeutics on a larger than necessary group/the wrong subjects. Bad on many levels.

These challenges underscore the value of biomarkers--for diagnosis and also for measuring progression. MJFF continues to drive this part of the field with over $32 million dedicated to biomarker discovery since 2002 and now the $45 million PPMI study. http://www.michaeljfox.org/living_PPMI.cfm

As you may recall (earlier threads) GE won FDA approval of it's DaTscan product. http://www.prnewswire.com/news-relea...124642448.html
This imaging tool is approved to make differential diagnosis between PD and essential tremor. It will likely gain swift use (it is already being used in Europe and in clinical research in the US) to aid in diagnosing PD. An exciting step forward. (PS--it is an inclusion criteria for our PPMI study that is looking to distinguish markers of disease progression in PD patients/controls).

One additional comment...the idea of l-dopa challenge as a common strategy for diagnosing PD. I'm not a doctor, but I hope the profession continues to improve it's understanding of the current standards of care and we see less of this approach.

I believe PD patients can play a critical role in helping education others. I believe that folks who suspect PD often reach out to known patients in their community for advice/information. Patients can both validate these challenges and provide a sense of context but also guide suspected PD patients to specialists (who now will more commonly have better tools to assist in diagnosis). Hopefully we can improve this situation are around.

Debi