This week's Modern Healthcare has an interesting article speculating on whether single-vendor RHIOs, which are rare today, could become a dominant model in the future. They cite as examples Inland Northwest Health Services from Washington state (which is based on the Meditech platform), and EHR of Rhode Island, a physician consortium working with eClinicalWorks.
I think the point of the article is an interesting one, but the examples they cite essentially answer the question of whether this will be a dominant model -- I don't think it will. Both INHS and EHRRI are very ideosyncratic models. INHS has integrated nicely on the inpatient side, but have very little penetration in the ambulatory side, which is always the hardest. I'm not even sure that EHRRI really qualifies as a RHIO -- they're doing excellent work, and have a very good model, but they're really an EHR purchasing/service consortium, not a health exchange.
MAeHC does have a single-vendor RHIO (of sorts) in North Adams, where all physicians are using the same EHR vendor who is also creating the HIE solution (eClinicalWorks). It's not a true single vendor solution because the hospital is on Meditech. We are certainly seeing lots of benefits in terms of ease of interoperability and richer exchange, and managing a single vendor is much easier than the alternative (this is not a trivial issue -- it's a big deal). However, North Adams is also a very ideosyncratic community that may not be widely applicable.
The key here is what gets the highest adoption. Consumer choice theory and empirical research suggest that greater choice will yield higher demand, but too much choice is paralyzing and confusing and may undercut demand. (I can confirm the latter -- I always dread having to buy more toothpaste because of the entire row of options that my local CVS puts in front of me.) This is why MAeHC offered partipating physicians choice but from a set of pre-qualified vendors. Given that "analysis paralysis" is a big barrier to adoption for many practices, this seems to be a good compromise formula for getting high adoption.
There are few, if any, EHRs that are optimal for all types of practices, so going with a single vendor will shut out some participants in most cases. It's possible that a hospital can drive physicians to a single solution based on their hospital platform, but my experience with the ambulatory products offered by the hospital vendors is that they sacrifice a little on the features side but in return for high interoperability with the hospital. Given the trend toward hospitalists and looser affiliation of ambulatory docs with their local hospital, I suspect that fewer and fewer physicians will be willing to make this trade in the future.