Morningstar this week unveiled its inaugural Morningstar Awards for U.S. exchange-traded funds that measures a fund's ability to track its index and its ease of tradability, among other factors, and places less emphasis on historic returns than previous awards systems.

The winners from across 37 fund categories were announced at the investment research firm's third annual ETF Invest Conference in Chicago. In addition, Morningstar named the best ETF providers in five asset classes.

Morningstar's methodology recognizes risk-adjusted outperformance versus a relevant peer group over the past one- and three-year periods. Category winners were highest ranked in terms of total cost of ownership and risk-adjusted returns.

"Costs are important to ETF investors, and the total cost of holding an ETF goes beyond simple expense ratios, which is why the awards also consider estimated holding costs and liquidity costs," said Paul Justice, Morningstar's director of research for passive funds, North America.

Morningstar's 37 categories contain at least five eligible funds, and the categories fall within one of five U.S. broad asset classes. The list of individual fund winners can be found at

The winners for best providers within the five asset classes were:

Commodities: iPath ETNs
International Stock: iShares
Sector Stock: Vanguard
Taxable Bond: iShares
U.S. Stock: Vanguard