An article in The New York Times by Steve Lohr published March 5, 2012 reports on a study using existing data that concluded that availability of digital records may not cut health costs. Someone expressed doubt in the findings because they were based on correlations in existing data rather than a controlled test intended to test the hypothesis regarding electronic records and costs.
In my opinion, not every study requires a method like that of a clinical trial and it is both valid and cost-effective to make use of existing data in responsible ways. Correlation certainly does not prove causality, of course. But I believe the discovery of interesting correlations resulting from hypothesis-based research can be worthy of the attention of professionals. I am not advocating for just mindlessly searching available data for any possible relationship among variables and then pretending to have completed disciplined research.
It is reasonable to anticipate that computerized medical offices have the potential to both save money (by reducing the need for repetition of tests already taken) and to spend additional money as the availability of data stored in electronic records drives the propensity of physicians and patients to want still more data. The new iPad 3 with its high resolution screen is likely to push the, "let's get more images" propensity further. Medical providers want to do what is possible and the availability of higher-quality data easily accessible extends what is possible.