The Electronic Entertainment Design and Research (EEDAR) recently released the first results of a study on Xbox 360 Achievements, coming to the conclusion that games with more Xbox 360 Achievements tend to generate both greater sales and higher Metacritic review scores.

The diversity of Achievements is also noted as having an effect on sell-through, with the study suggesting that games with online-based Achievements sell up to 50% more copies than those without them on.

Of course, these trends may have simpler explanations: higher profile games are more likely to have larger Achievement lists based on the quality of their development. Giving much sales credit to a larger list of Achievements seems a reach. Still, the EEDAR may be on to something when it comes to marketing.

Games that saw their Achievement lists announced prior to release were found to be more successful than games that kept their list secret. For instance, a game with a larger list may indicate the game has a greater replay value, thus creating further interest in the title.

In addition, incorporating Achievements into viral marketing was shown to increase business by 50%.

The conclusion? Using Achievements as a tool to entice and excite gamers may be paying off for clever developers.

"Our research shows that incentives such as Accomplishments impact sales choices such as which game title to buy and which platform to buy it on; they also extend the replayability of a title," said Geoffrey Zatkin of EEDAR. "Consumers want their games to include both variety and abundance of Accomplishments."