A study paid for by the makers of anti-wrinkle injection Dysport found that it is better at reducing crow's feet than its popular competitor, Botox.

On Monday, the makers of Dysport announced a study comparing two different kinds of botulinum toxins. The double-blind study was funded by Dysport and published in Archives of Facial Plastic Surgery.

During a 30-day trial period, researchers injected patients with both medications to the muscles that close the eyelids.

In this study, we were injecting the two agents in the same person's face, shared Dr. Cory Mass, a San Francisco based facial plastic surgeon and lead author of the study.

The sites were far enough away from each other so that the agents could not have an effect on each other, and by doing a split-face study, we have taken all the variables out of the equation, like age, gender and ethnicity, he said.

The result showed that two-thirds of the patients preferred the Dysport side of their face; one-third chose the Botox side.

However neither the researchers nor patients were able to note a significant difference between the two when the facial muscles were relaxed.