Two-Step Flow of Communication Theory — Key Points
The Two-Step Flow Concept
Mass media diffusion is not always direct; a two-stage process often occurs: the initial release of news via mass media is followed by word-of-mouth diffusion from more informed individuals to others.
Core idea originates from the Erie County study (1940) on the presidential election, which uncovered the role of interpersonal communication in shaping voting behavior.
The People’s Choice Project: Background and Design
Study of how voters make up their minds during a presidential election (Roosevelt vs. Willkie) conducted in residents of Erie County, , starting in 1940.
Key design feature: repeated interviews with the same panel (main panel) seven times, plus four control panels of the same size to test for biases due to repeated interviewing.
Published as The People’s Choice (1944); later editions in 1948 and 1968.
Goals: determine conditions that shape political behavior and why people vote as they do.
Site and Unique Design
Erie County was chosen because it was small enough for repeated interviewing and representative of national trends in voting.
County features: multiple newspapers, proximity to major markets, industrial and agricultural mix; voting patterns historically mirrored national trends.
The design allowed assessing potential interviewer effects via a panel vs control panels.
The Results: Predispositions and Media Effects
Predispositions (pre-existing factors):
Socioeconomic status (SES) influenced vote preference (higher SES leaned toward Willkie; laboring class leaned away).
Religion and age also mattered: Catholics favored Roosevelt; Protestants and older voters leaned toward Willkie; younger voters toward Roosevelt.
Media campaign effects occurred in stages: activation, reinforcement, and conversion.
Activation, Reinforcement, and Conversion
Activation: media messages increase attention and exposure, which enhances interest; process becomes self-reinforcing as exposure grows.
Reinforcement: many voters were already committed to their party; propaganda aimed to prevent defections.
Conversion: few voters actually switched sides due to media messages; about of voters in the main sample changed their minds during the study period.
Radio vs. Newspapers: radio was a newer, influential medium; Roosevelt’s radio presence contributed to his appeal.
The Discovery: Opinion Leaders and the Two-Step Flow
Unexpected finding: conversations with others (friends, family, coworkers) were a major source of information and interpretation, more so than mass media for many respondents.
Opinion leaders: individuals who pay close attention to media content, read extensively, and pass on information and interpretations to others.
The two-step flow: media → opinion leaders → others (word-of-mouth).
This flow is not limited to elections; it extends to other content such as news, marketing, and entertainment.
The Nature and Role of Opinion Leaders
Opinion leaders exist at all levels of society (not restricted to the upscale or privileged).
A factory worker, for example, may be influenced by another worker rather than by a higher-status individual.
Interpersonal contact is a dominant channel for political information (e.g.,
more respondents discuss the election than read or hear media content on it).
Why Personal Influence Outperforms Mass Media
Opinion leaders possess credibility: people trust neighbors, friends, and coworkers more than media figures or propaganda.
They can adapt messages to resistance and local contexts; mass media cannot tailor to individuals.
The combination of media exposure and personal interpretation through networks drives social diffusion.
Additional Studies Supporting the Two-Step/ Multi-Step View
Rovere Study (Robert K. Merton, 1940s): followed up on Erie County to identify and interview key information sources; showed opinion leadership outside elections.
Decatur Study (1945–46): snowball approach; found that opinion leadership influences extend beyond political campaigns to marketing, entertainment, and public affairs; revealed multi-step diffusion in networks.
Medical adoption study: doctors influenced by colleagues when adopting new drugs; highlighted professional networks in decision making.
These studies reinforced the idea that personal influence is a significant channel of information.
Formal Summary of the Two-Step Flow Theory
1) Mass media provide a broad, continuous flow of information; most people attend selectively.
2) A subset of individuals attend more fully and become more knowledgeable on certain topics.
3) These individuals become opinion leaders, trusted sources for others.
4) Opinion leaders pass on information and interpretations to their followers.
5) Therefore, mass communication often moves in two stages: media to opinion leaders, then to others via word-of-mouth.
Distortion in Interpersonal Communication
A key question: how accurate is information as it flows through interpersonal networks?
The two-step framework often emphasizes opinion leaders, but content distortion is also a concern.
Allport & Postman (1947) describe a three-part embedding process in rumors: leveling, sharpening, assimilation.
Leveling: messages become shorter and less detailed over time.
Sharpening: central details become dominant;
Assimilation: details shift to fit attitudes or stereotypes of listeners.
DeFleur & Cronin (1991): an experimental recall study showed that while newspaper sources yielded better recall than TV sources, both chains exhibited leveling and some loss of details, but the core ideas remained coherent; multi-step diffusion effects warrant further study.
The rumor literature helps illustrate potential distortions in multistep diffusion and underscores that content quality can degrade differently from audience to audience.
Implications for Mass Communication Theory
The Erie County findings helped overturn the Magic Bullet Theory, which posited direct, uniform effects of mass media.
The two-step flow emphasizes the mediating role of social networks and opinion leaders in shaping, filtering, and interpreting media messages.
Ongoing relevance: the interplay between media content, opinion leaders, and interpersonal diffusion continues to shape political behavior, marketing, and public discourse.
Quick Takeaways for Exam Review
Two-step flow: media → opinion leaders → others; diffusion is not uniformly direct.
Opinion leaders exist at all levels of SES and are trusted because of personal connections.
Activation, Reinforcement, and Conversion describe how media campaigns influence voters, with conversion being relatively limited.
Interpersonal communication often exceeds media channels in informing and shaping opinions.
Distortion in diffusion can occur via leveling, sharpening, and assimilation; remember the rumor framework and the DeFleur & Cronin study for recall patterns.
The Rovere, Decatur, and physician-adoption studies extend the idea of two-step flow beyond politics to broader social influence networks.