Participant Media's Impact Index

By Johanna Blakley, Managing Director and Director of Research

The New York Times devoted significant ink this week to The Participant Index (TPI), an effort by Participant Media to quantify and compare the relative social impact of films, TV shows and online video. The article also mentioned the Lear Center's $4.2 million Media Impact Project, which has consulted on the development of TPI.

Participant approached the Lear Center because of its academic expertise in measuring the impact of educational messages embedded in entertainment content. The Center's Hollywood, Health & Society program has partnered with the CDC for the last 14 years to look at how health storylines in popular TV shows affect viewers' knowledge, attitudes and behavior. The survey component of

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TPI includes a combination of questions that have become standard in entertainment education evaluation: the "transportation scale" identifies the type of emotional involvement that the entertainment content triggered and the outcome questions indicate what real-world actions a subject has taken after exposure to the content. TPI combines these two measures to create a score for each piece of video content in the study.

In a separate research project, Participant Media asked the Lear Center to evaluate the impact of three of their films: the documentaries Food, Inc.and Waiting for Superman, and Steven Soderbergh's feature film, Contagion. The Lear Center adapted propensity score matching techniques used in clinical research to address 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. A propensity score methodology - not used in TPI so far - enables researchers 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. 

We are excited to see for-profit companies like Participant Media devote significant resources and time to measuring the impact of media. We hope that many others will follow in their path.