Gold ETFs are often described as an inflation hedge but recent academic research suggests the precious metal is more dependent on emerging market demand, particularly from central banks that hold less gold than their counterparts in developed countries.

“Assuming that gold moved in lockstep with the CPI, the implied price would be about $780 an ounce, according to Duke University Professor Campbell R. Harvey and his collaborator, Claude B. Erb,” Bloomberg News reports.

Gold is trading back above $1,600 an ounce as traders speculate on the odds of further monetary easing before next week’s Federal Reserve meeting. [Gold ETFs Eye Fed, Europe]

Since the gold bull market started in about 2001, prices have risen more than sevenfold.

“If gold is an inflation hedge, then on average its real return should be zero,” Erb and Harvey wrote, according to the Bloomberg report. Instead, returns from 2000 through March of this year averaged 13% a year on an inflation-adjusted basis.

Gold ETFs such as SPDR Gold Shares (NYSEArca: GLD), iShares Gold Trust (NYSEArca: IAU) and ETFS Physical Swiss Gold Shares (NYSEArca: SGOL) have likely fueled the metal’s rise since they have made it easier for more investors to buy gold.

“Global ETF investor positions have continued to trend up in both gold and silver, reflecting the fact that long term price supports such as negative real interest rates, currency debasement and sovereign/financial sector default risk, and rising emerging market/central bank demand remain embedded in the 2012 outlook,” ETF Securities said in a report earlier this year. [Measuring the Impact of Gold ETFs]