Under an agreement with the Attorney General, Andrew Cuomo, the health insurance company Aetna is adding transparency and oversight to its doctor-ranking program.

Aetna, the third-largest health insurer in the country, will implement the changes nationwide, according to an announcement yesterday.

Previously, Aetna’s ranking program did not disclose how much of the evaluation process was based on cost, and how much was based on quality.

Under the new agreement, the insurer will fully disclose to consumers how doctors are ranked. Aetna’s agreement with Mr. Cuomo follows a similar one by the insurer Cigna. Both agreements were reached after Mr. Cuomo opened an inquiry into physician-ranking programs of several carriers.

So far, changes have garnered support from consumer groups and physicians.