Alabama Drowsy Driving Advisory system
Also: DDA signs
A series of roadside warning and advisory signs for drowsy drivers placed upstream of rural interstate rest areas in Alabama, chosen from crash analysis.
- Years
- 2020–now
- Country
- United States
- Topic
- SleepTraffic safety
- Asks people to
- Substitute
- Strategy
- Environmental supportSimple instruction
- Channel
- Outdoor
- Audience
- General publicInterstate drivers
Evidence
Quasi-experimentalPositive
Empirical Bayes before-after study three years after installation: total crashes down an estimated 64% and expanded-definition drowsy crashes down 49%, attributed to signs and rest areas together, not signs alone.
Sponsor (who paid)
- Alabama Department of Transportation (implied; research by University of South Alabama) State local government
Credits (who made it)
Not recorded yet.
Sources
- Safety evaluation of drowsy driving advisory system: Alabama case study evaluation · 2020 · DOI 10.1016/j.jsr.2020.04.005 · PMID 32951795
Research notes
Created 2026-10-23 from the sleep campaign literature search (PubMed and web search; OpenAlex was unreachable), see docs/sleep-campaigns-literature.md. Findings are paraphrased from abstracts, not full texts; official URLs come from search results and were not opened. Sponsor agency not stated in abstract; check full text for ALDOT role and sign wording. startYear 2020 is the earliest dated source found, not a confirmed launch year.
Record cases/al-drowsy-driving-advisory-signs.json, updated 2026-10-23· Link to this campaign