Study leader Jane Pendergast, director of the Center for Public Health Studies at the University of Iowa, and colleagues analyzed five years of private health insurance claims -- 2003 to 2007 -- involving nearly 63,000 outpatient physical therapy data from a Midwest insurer on beneficiaries ages 18-64 in Iowa and South Dakota.
More than 45,000 were classified as physician-referred if the patient had a physician claim from a reasonable referral source in the 30 days before the start of physical therapy. More than 17,000 were classified as "self-referred" to physical therapists.
The study, published in the journal Health Services Research, found self-referred patients had fewer physical therapy visits and lower allowable amounts during the episode of care, after adjusting for age, gender, diagnosis, illness severity and calendar year.
In addition, overall related healthcare use -- care related to the problem for which physical therapy was received, but not physical therapy treatment -- was lower in the self-referred group.
"Our findings do not support the assertion that self-referral leads to overuse of care or discontinuity in care, based on a very large population of individuals in a common private health insurance plan with no requirement for physical therapy referral or prohibition on patient self-referral," the study authors said in a statement.