Customer testimonials inspire confidence and strengthen loyalty. Ecommerce websites can use them to “counter major buying objections, add customer credibility to benefit statements, and launch the ‘band wagon effect’ (people like to jump on the band wagon with others who share their same interests, values, and needs),” says Pat Friesen, an award-winning copywriter and marketing consultant who has worked with a variety of online retailers, including Helzberg Diamonds, NordicTrack, Hasbro, and Hershey’s.

But not all kudos are created equal. How can an online business tap into the customer voice that best encourages other patrons to shop?

One company tested the effectiveness of three different customer testimonials located on a banner under the website’s navigation. Each banner offered free shipping in addition to the variable testimonial.

The test was intended to determine which message resulted in the most favorable shopping activity on the site.

Good thing they decided to test, because the results were definitive. Testimonial A was the resounding winner, likely owing its success to the inclusion of specifics (“enormous selection of items” and “high quality brands”) about why the customer liked to shop on their website, Friesen explains.

She adds that marketers should test the use of testimonials that represent a broad cross-section of customers, including both genders as well as a wide range of ages and geographies, to find the right mix that helps motivate visitors to make purchases. And don’t forget that how you merchandise testimonials—as comments, reviews, insights, etc.—sets your visitors’ expectations for the level of information they will get from reading what other customers have to say.