A posting on the Wall Street Journal Health blog quotes Steve Lieber of HIMSS as saying that PHRs may be less trusted by doctors and therefore slow down care, such as emergency or urgent care. The example given is having a PHR on a thumb drive - how does the physician know that the information, some of which could be life-threatening such as allergies, is reliable.
This is another argument for some kind of certification of PHRs and also providing a way to show the source of information in a PHR - is it from a provider, entered by the patient, claims information or something else.

Technorati: PHRs