CHICAGO — About 70% of consumers won’t try a new menu item at restaurants, according to a new report from The NPD Group, Chicago.

Of those who do, 17% of survey respondents said they will order a new item, and 10% will try a limited-time offer. Perceptions of taste and visual appeal, as well as healthfulness and price, may drive a consumer to order something new, but generally diners will trade in their pre-planned menu item only if the unfamiliar product is the same food type, NPD said.

The incidence of first-time trial is higher at casual-dining restaurants, where consumers may consider the quality and freshness of ingredients used in the new item and whether they can share it with others. Half of new items ordered are main dishes, with sandwiches accounting for almost half of the remaining new items ordered.

“Insight into the reasons why consumers try a food or beverage menu item that they have not purchased before provides restaurant operators with the knowledge required for successful product innovation, introduction and marketing,” said Bonnie Riggs, restaurant analyst for the NPD Group. “In addition, stimulating menu-item trial and delivering a satisfying experience should lead to repeat visits and sustained customer loyalty.”

Menu innovation last year reflected a mix of better-for-you items and unusual indulgences, such as Dunkin’ Donuts’ bacon egg sandwich on a halved glazed donut and Sonic Drive-In’s peanut butter bacon milkshake.

“People are going to order it because it’s fun and funny, but it’s not something that someone is going to order once a week,” said Mary Chapman, director of product innovation at Chicago-based research firm Technomic, Inc. “Restaurant chains put things on and take things off all the time, and so why not put something on that’s really crazy?”