While Oscar has had unexpected success so far with its simple plan option, flat deductible offerings are not unique in the health insurance world.
Kev Coleman, head of research and data for the insurance price comparison site HealthPocket.com, said an analysis of government data representing thousands of Affordable Care Act health plans nationally found that 22 percent had annual limits on out-of-pocket costs that are equal to their deductibles, meaning there were no co-payments or co-insurance fees for covered services after the deductibles were satisfied.
Coleman said flat deductible plans are: "Leave the consumer to pay out-of-pocket for routine doctor visits, lab tests and other care, but guard the consumer against medical events that could bring bankruptcy."
"This model is particularly attractive to consumers with low-to-no annual health-care use who are more worried about the costs of a heart attack or cancer than a visit to a doctor," Coleman said.
That point was echoed by Judimarie Thomas, a spokeswoman for Independence Blue Cross, a large insurer that serves Pennsylvania and New Jersey through an affiliate.
Independence's 14 health plan offerings in Pennsylvania for 2015 include just one flat-deductible plan, the Bronze Personal Choice PPO Reserve Plan, which has a $6,000 annual deductible.
"Many consumers did choose our Bronze" plan, "consumers that did not anticipate using a lot of health-care services," Thomas said.
But Gary Claxton, vice president of the Kaiser Family Foundation, the health policy research group, said the high deductibles seen in Oscar's simple plans and other comparable offerings by other insurers can be daunting for consumers.
"People don't like high deductibles," Claxton said. "A lot of people don't have a lot of cash."
But, Claxton noted, an attractive feature of high-deductible plans is that "you basically get about the cheapest premiums that you can get."
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"The other part is people know what their exposure is as long as they stay in network," he said. "It's something that you can understand more easily."
Asked why more insurers don't offer plans that have flat deductibles and eliminate the schedules of co-payments and co-insurance that can confuse consumers shopping for coverage, Claxton laughed.
"From an insurer's perspective, it's so the plans aren't directly comparable," he said. "They also want to load cost-sharing into different areas where they have different problems."
Also, he said, "they do consumer research and they know there's a certain section of consumers that are afraid of higher deductibles."