When it comes to their marketing efforts and investor perception, three mutual fund firms stand above the rest, according to Phoenix Marketing International.

Fidelity, Vanguard and USAA consistently came in as the top three fund companies in studies conducted by Phoenix, a Rhinebeck, N.Y.-based research organization, over a two-year period.

Phoenix asked 1,500 people, ages 35 to 64 with $100,000 in investable assets and $100,000 in income, to evaluate the mutual fund companies most successful at marketing.

The evaluations were based on the companies’ brand and advertising performance; the respondents’ understanding of the types of retirement products and services associated with the companies; the companies’ brand positioning next to their competitors; and the retirement offerings investors were most interested in, specifically within the next three months.

Phoenix performs surveys twice a year, in May and November. In the most recent two surveys, Fidelity returned to the top position after Vanguard beat the firm in May 2012. Fidelity had won the top spot in both 2011 surveys. USAA continued to rank third.

Other funds rounding out the top five were TIAA-CREF and T. Rowe Price in November 2012 and American Funds and Charles Schwab in the May 2012.

The changing rankings indicate slight shifts in investors’ impressions of a company, Phoenix says.