According to Beth Beaudin-Seiler, lead author of the study and senior analyst at Altarum, the study's results bear out other research that indicates that low-value services are more common in some areas of the country than in others. States with less low-value care might also have a tough time in accessing care; in addition, the report says, many that have smaller percentages of low-value care include significant rural areas.

While the study doesn't explore the reasons for variations, says Beaudin-Seiler, "It seems to be more local practices that are providing low-value care rather than let's say a type of insurance carrier or a patient demographic," with local providers not necessarily educated on changing behavior or lacking incentives to do so.

In fact, providers may be encouraged by fee-for-service reimbursement to continue low-value services—the most common of which are annual Pap smears for women ages 30–65 (perhaps due to lack of knowledge on the part of the physician on the latest practice guidelines), routine Vitamin D screening (which could simply be bundled with other tests, rather than specifically being ordered by the doctor) and the use of five branded drugs despite the availability of generics.

The analysis estimates that nationwide, an estimated $5.5 billion was spent overall on the 20 low-value services in 2015.

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