The Robustness of Fear Appeals:
A Multilab Registered Replication Study
Replicating: Witte, K. (1994). Fear control and danger control: A test of the extended parallel process model (EPPM). Communication Monographs, 61, 113–134.
Kim Witte's Extended Parallel Process Model (EPPM) is one of the most influential theories in health communication. Cited over 5,000 times and taught in textbooks worldwide, it underlies major public health campaigns — yet its foundational 1994 empirical test was conducted with only 146 students, never included a 6-week follow-up in its replication record, and has not been tested for generalisability across cultures and populations.
This project conducts the first large-scale, preregistered, multilab replication of the EPPM, recruiting labs across five countries to test whether the core threat × efficacy interaction holds at scale, what the unbiased effect size is, and what moderates cross-lab variation. Stage 1 preregistration will be submitted to a journal offering Registered Replication Reports — guaranteeing publication regardless of outcome.
Research Questions
- Do the core EPPM predictions replicate across labs and populations?
- What is the unbiased effect size for threat and efficacy appraisals on behavioural intentions?
- Does the critical threat × efficacy interaction hold in a large, preregistered design?
- Do maladaptive responses mediate behavioural outcomes?
- What moderators drive heterogeneity across labs?
Project Timeline
Project launch & website live
Stage 1 preregistration submitted
Protocol finalised; labs recruited
Pilot testing begins
Data collection ends
Meta-analysis
Manuscript submitted