Research study finds that a film can have a measurable impact on audience behavior

As Academy Award voters mark their ballots, researchers at the USC Annenberg Norman Lear Center released a study measuring a movie's power to change the behavior of people who see it. Using an innovative instrument developed by the Lear Center, the study of more than 20,000 people found that those who saw the 2010 Oscar® nominee Food, Inc. had significantly changed their eating and food shopping habits. Food, Inc. viewers were significantly more likely to: 

  • encourage their friends, family & colleagues to learn more about food safety
  • shop at their local farmers market
  • eat healthy food
  • consistently buy organic or sustainable food

This was compared to non-viewers who were virtually identical in 17 traits, including their degree of interest in sustainable agriculture and their past efforts to improve food safety. A video presentation of key findings, which were first announced at TEDxPhoenix, is available on the TEDx YouTube channel. The Lear Center's new survey methodology adapts propensity score matching techniques used in clinical research as well as communication studies. It specifically addresses the key problem of "selection bias" among movie viewers: only certain people choose to see certain films, making it very difficult for researchers to expose people randomly to a movie and to determine the actual impact of the film. The Lear Center's methodology enables researchers with a large number of survey respondents to create a detailed profile of likely viewers of a film, and to compare very similar viewers who saw the film with those who did not. Unlike typical survey research, this method allows researchers to construct something similar to a classic study design where individuals are randomly assigned to a treatment group and a control group. "Filmmakers who want their movies to impact people's opinions or behavior now have a way to find that out," said Johanna Blakley, managing director and director of research at the Norman Lear Center, and the principal investigator for this study. "Over half of Food, Inc. viewers said, 'This film changed my life.' Our research tells us exactly how those lives were changed." "Entertainment affects audiences," said USC Annenberg professor and Lear Center director Martin Kaplan. "The challenge for scholars has been measuring that impact, especially for mass media, without requiring a fortune to spend on valid datasets. With this new Lear Center approach, we're now able to move ahead with studies of the effects of more movies, both documentaries and scripted features." Food, Inc. director Robert Kenner said, "As a filmmaker, it's both encouraging and gratifying to see quantitative results that these films have a profound impact. I am thankful to Blakley and USC for their thoughtful research and analysis." Additional findings about Food, Inc. viewers included a significantly higher likelihood to contribute time or money to support organized efforts around:

  • improving the treatment of animals in the food industry
  • improving food and drinks served in schools
  • passing legislation that improves food safety
  • passing legislation that offers fair wages and job protection to farm workers and food processors

Funding for the study, which was independently designed, conducted and released by the Norman Lear Center, was provided by Participant Media, the company that co-financed Food, Inc., as well as the current Best Picture nominee The Help. The research team included principal investigator Johanna Blakley, Ph.D., and a team of research analysts: chief research consultant Sheena Nahm, Ph.D., MPH and USC doctoral students Grace Huang, MPH; Heesung Shin, MPH, and LeeAnn Sangalang. More information about this research can be found here.