The group of seven, all members of the National Commission for the Forecast and Prevention of Major Risks, were also ordered to pay more than nine million euros in damages.
They were accused of making a falsely reassuring statement before the deadly quake after studying tremors that had hit the medieval city.
Their defence had argued that there was no way to predict major earthquakes, even in a seismically active area.
More than 5000 people, including 80 New Zealanders and GNS scientists, signed an open letter to Italian President Giorgio Napolitano backing the defendants as they went on trial last year.
GNS today said the case was "a complex matter", involving legal, scientific, emotional and political aspects, and concerned a very specific set of circumstances.
"In this instance, the scientists and government official were found to be deficient in the way they communicated the state of scientific knowledge and the possible threat of a large damaging earthquake," the statement said.
"The communication of risk and uncertainty is a challenging area for scientists. But to suggest that repeated small earthquakes in the area of L'Aquila were favourable because they unloaded seismic stress and reduced the chance of a big quake was unwise in our view.
"This, and other comments from officials, apparently inhibited many people from taking actions that might have saved their lives."
GNS say it's difficult to make any direct comparisons between L'Aquila and New Zealand.
However, the case highlights the need for scientists to communicate meaningful information about natural hazards and probabilistic information to government agencies and the public.
GNS updates its aftershock probabilities for the Canterbury region on a monthly basis and over the past two years has undertaken "hundreds of communications" via public seminars, briefings to government agencies, written reports, video and Youtube clips, and press releases.
"Scientists must weigh up the evidence carefully and be cautious about the possibility of saying too little and delivering a false sense of security that could cause complacency, or delivering a false alarm that could cause panic," GNS said.
"There is a need for balanced information so government agencies and the public have the ability to make informed decisions about their actions."
The convicted men - scientists, Enzo Boschi, Giulio Selvaggi, Franco Barberi, Mauro Dolce, Gian Michele Calvi, Claudio Eva and senior Civil Protection Authority official Bernardo De Bernardis - have vowed to appeal the sentence.
Dr Chris Gallavin, Dean of University of Canterbury's law school, said the Italian court decision would not set a legal precedent in New Zealand.
Instead, he attributed the decision to a "quirk" of the Italian criminal justice system.
"It's not scientists that have killed the people - it's the earthquake that caused the deaths," he said.
