In 2015, when health insurer enthusiasm about the AffordableCare Act was peaking, ACA coverage expansion programsseemed to have a noticeable effect on U.S. residents' access tomedical care.

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Susan Hayes and other analysts at the New York-basedCommonwealth Fund, a nonprofit organization that has stronglysupported the goals of the ACA, published a report supporting thatconclusion in a new look at federal government healthsurvey data.

Before ACA coverage expansion programs came to life, somecritics asked whether the programs would actually expand the amountof care people were getting, or simply increase the amount of cashproviders received for care they would have provided anyway.

In the new issue brief, the Commonwealth Fund analysts writethat the percentage of adults who said they had gone without carein the past year because of cost fell to 13 percent in 2015, from16 percent in 2013.

The percentage of adults with chronic health problems, such asasthma or pre-diabetes, who had not had a checkup or other routinecare in the previous two years, fell to 13 percent, from 14percent. In theory, an increase in access to care for people at ahigh risk of developing catastrophic health problems could reducethe number of people with disabilities, the number who needlong-term care services, and the number who die.

Related: ACA Medicaid expansion: Game changer for thepoor

The ACA did not expand dental coverage for adults.

The Commonwealth Fund analysts found that the percentage of U.S.adults who had not had a dental visit within the past yearincreased to 16 percent in 2014, from 15 percent in 2012. That's asign that the ACA itself, rather than general economic or healthinsurance trends, helped improve people's access to care, theanalysts say.

The analysts found four states in which at-risk adults' accessto checkups improved by 4 percentage points.

The no-checkup rate for at-risk adults fell to 17 percent, from21 percent, in Oklahoma; to 14 percent, from 17 percent, inCalifornia; to 11 percent, from 15 percent, in Kentucky; and to 6percent, from 10 percent, in Rhode Island.

The no-checkup rate for at risk-adults fell by 3 percentagepoints in Arizona, Mississippi and the District of Columbia.

Related: GOP report: State ACA exchanges willcollapse

Problems with operating losses and ACA insurer stabilizationprograms began to reduce insurers' interest in late 2015. Somehealth coverage ownership figures began to reverse this year, andanalysts do not yet have the data to know what has been happeningto coverage access this year or might happen to access in 2017.