Republicans on the Senate Budget Committee have pressed the Congressional Budget Office to release details of the forthcoming new health insurance simulation model.
In pointed language, the letter led by committee Chair Sen. Mike Enzi (R-Wyo.) suggested that the CBO should test its model with a do-over of the original estimate of the federal spending and health insurance coverage for the Affordable Care Act "to determine whether the agency's estimate would have been closer to the actual, observed amounts since (the ACA's) enactment."
The CBO's health insurance projections rankled Republicans last year throughout their repeal-and-replace effort when the independent agency depicted drastic coverage losses should either the House or Senate GOP overhaul bills pass.
In the summer of 2017, the White House went on the attack against the CBO's prediction that the Republican measures would cut 22 million from insurance coverage within a decade, saying the analysis was based on faulty numbers. The agency had forecast 25 million would be covered by the ACA in 2017, but in that year just over 10 million had individual market insurance.
The attacks drove eight former CBO directors to defend the agency's nonpartisan objectivity in an open letter to congressional leadership, noting that the CBO makes no policy recommendations and "regularly consults with researchers and practitioners with a wide range of views," while also disclosing its analytic techniques and forecast records.
Last month, the Senate Budget Committee convened a hearing after the CBO released a report updating Congress about its "efforts to be transparent" in order to "enhance the credibility of CBO's analyses and processes, promote a thorough understanding of its work, and help people gauge how estimates might change if policies or circumstances differed."
The agency is currently testing its new health insurance simulation model, which it plans to start using for its analyses and projections next spring. Republican senators want to know the data and key assumptions that the model is built on "before it is adopted" and have urged the CBO to test it against outside validation before deploying.
Outside validation includes Obamacare coverage numbers.
"This type of real-world testing not only could serve to validate the model but would help further the goal of developing a new model that is capable of producing more accurate estimates for Members of Congress and the public," the senators wrote.