A recent study from Dynamic Logic found that the size of online ads is not the most important factor in generating ad awareness and purchase intent.

Instead, ads that are integrated into the content of the page are most effective, with rectangles and half-banners leading the way.

The worst-performing ad shapes were button and full banner ads, the survey found.

"We continue to believe that creative quality is the most important factor driving the success of online advertising," said Ken Mallon, Dynamic Logic's senior vice president of custom solutions. "However, it will be interesting to see how the new, larger ad formats that publishers are beginning to debut will rank next to the more traditional online ad formats."

In addition, the study found that ad campaigns using rich media with video were the most effective, while those featuring simple flash - which are used most commonly by marketers - are least effective.

This is important news for small business owners who are interested in digital marketing strategies, as rich media with video was found to generate higher brand awareness, online ad awareness, message association, brand favorability and purchase intent than rich media without video or simple flash.

With the number of online users expected to reach 2.2 billion in the next five years, according to Forrester Research, online ad effectiveness has become an important issue for many small businesses.