Another study has determined graphic warning labels on cigarette packs may gain the attention of smokers better than current warning phrases, but not necessarily spur them to quit.

The study from UNC Chapel Hill researchers was released online Monday at the Intern Medicine website for the Journal of American Medical Association.

Researchers had 1,891 adult smokers in California and North Carolina complete a four-week study conducted between September 2014 and August 2015.

They were shown either the Surgeon General’s warning label or a graphic image with smoke coming out of a tracheal hole, diseased lungs and gums, and a man who appears deathly ill.

About 40 percent of participants said they were more likely to consider quitting after exposure to the graphic images, compared with 34 percent with the text warning.

“Pictorial warnings also increased forgoing a cigarette, intentions to quit smoking, negative emotional reactions, thinking about the harms of smoking, and conversations about quitting,” researchers said.

“Our trial findings suggest that implementing pictorial warnings on cigarette packs in the United States would discourage smoking.”

However, as has been the rub in other studies, the researchers also concluded the graphic images’ effect on smoking behavior “remains uncertain.”

In December 2010, a Food and Drug Administration study found putting graphic-warning labels on cigarette packs may stir emotions, but not lead to quitting.

It’s been more than three years since there’s been legal or regulatory movement on graphic warnings, particularly on what they will look like and when they will appear.

The legal question about the labels seemed settled after the U.S. Supreme Court declined in April 2013 to hear an appeal on the images from a group of tobacco manufacturers that include R.J. Reynolds Tobacco Co. and Lorillard Inc.

Nine labels were chosen by the FDA in June 2011. The labels had been scheduled to debut in September 2012.

“This new study adds to the extensive evidence from around the world that large, graphic health warnings are most effective at informing consumers about the health risks of smoking, discouraging children and other non-smokers from starting to smoke, and motivating smokers to quit,” Matt Myers, president of the Campaign for Tobacco-Free Kids, said in a statement.

However, two parallel legal cases with differing judicial opinions have put the initiative on hold.

Meanwhile, a Feb. 22 study published by University of Illinois researchers at the journal Communication Research suggests graphic images strike some people as manipulative, a reaction that could backfire on the attempt to steer individuals away from smoking.

Lead Illinois researchers Nicole LaVoie and Brian Quick said their goal was measuring whether individuals felt their behavioral freedom — also known as psychological reactance — was being threatened by a requirement for graphic warnings on cigarette packaging.

Researchers cited other studies addressing consumer warnings and perceived threats to freedom that cover gun control, legalizing marijuana, condom use, binge drinking, exercise, recycling and sunscreen use.

Stephen Pope, managing partner of research firm Spotlight Ideas of London, said most adults are aware of the risks and consequences of smoking.

“So if people chose to smoke, ghastly graphic images will be mentally ignored,” Pope said.

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