The World Bank repeatedly changed the methodology of one of its flagship economic reports over several years in ways it now says were unfair and misleading.

The World Bank’s chief economist, Paul Romer, told The Wall Street Journal on Friday he would correct and recalculate national rankings of business competitiveness in the report called “Doing Business” going back at least four years.

The revisions could be particularly relevant to Chile, whose standings have been volatile in recent years—and potentially tainted by political motivations of World Bank staff, Mr. Romer said.

The report is one of the most visible World Bank initiatives, ranking countries around the world by the competitiveness of their business environment. Countries compete against each other to improve their standings, and the report draws extensive international media coverage.