Health care fragmentation occurs when delivery of care is spread across an excessively large number of poorly coordinated providers. It is considered a potentially significant source of inefficiency in the U.S. health care system. Research summarized in the current edition of the National Bureau of Economic Research (NBER) Bulletin on Aging and Health finds that there are substantial regional differences in the degree of fragmentation.
The summary can be obtained at http://www.nber.org/aginghealth/2017no2/2017no2.pdf.