Accidents & injuries
Factors that swing accidental deaths
Factors that swing accidental deaths
Scroll sideways to see every factor →
Tap a pill to answer yours.
Where you sit
0 of 10 answered
Answer the 10 factors above to see which ones raise your own risk, which sit at the reference, and which the studies have no number for.
Relative risk versus each factor’s reference group; above the line is lower risk, below it higher.
Sources (13)Cummings P, Wells JD, Rivara FP, Accid Anal Prev 2003 · McEvoy SP, Stevenson MR, McCartt AT, et al., BMJ 2005 · Olivier & Creighton, Int J Epidemiol 2017 and 10 moreShow allHide
- [1]S. P. McEvoy et al. Role of mobile phones in motor vehicle crashes resulting in hospital attendance: a case-crossover study. BMJ, 331(7514):428, 2005. doi:10.1136/bmj.38537.397512.55 Evidence: Low
- [2]B. Taylor et al. The more you drink, the harder you fall: a systematic review and meta-analysis of how acute alcohol consumption and injury or collision risk increase together. Drug Alcohol Depend, 110(1-2):108-16, 2010. doi:10.1016/j.drugalcdep.2010.02.011 Evidence: Moderate
- [3]M. Karimi et al. Sleep apnea-related risk of motor vehicle accidents is reduced by continuous positive airway pressure: Swedish Traffic Accident Registry data. Sleep, 38(3):341-9, 2015. doi:10.5665/sleep.4486 Evidence: Low
- [4]S. Tregear et al. Continuous positive airway pressure reduces risk of motor vehicle crash among drivers with obstructive sleep apnea: systematic review and meta-analysis. Sleep, 33(10):1373-80, 2010. doi:10.1093/sleep/33.10.1373 Evidence: Moderate
- [5]P. Cummings, J. D. Wells, and F. P. Rivara. Estimating seat belt effectiveness using matched-pair cohort methods. Accid Anal Prev, 35(1):143-9, 2003. doi:10.1016/s0001-4575(01)00087-2 Evidence: Low
- [6]S. Chihuri and G. Li. Use of Prescription Opioids and Initiation of Fatal 2-Vehicle Crashes. JAMA Netw Open, 2(2):e188081, 2019. doi:10.1001/jamanetworkopen.2018.8081 Evidence: Low
- [7]C. Owsley et al. Impact of cataract surgery on motor vehicle crash involvement by older adults. JAMA, 288(7):841-9, 2002. doi:10.1001/jama.288.7.841 Evidence: Low
- [8]B. C. Tefft. Acute sleep deprivation and culpable motor vehicle crash involvement. Sleep, 41(10):zsy144, 2018. doi:10.1093/sleep/zsy144 Evidence: Low
- [9]O. Rogeberg and R. Elvik. The effects of cannabis intoxication on motor vehicle collision revisited and revised. Addiction, 111(8):1348-59, 2016. doi:10.1111/add.13347 Evidence: Moderate
- [10]J. Olivier and P. Creighton. Bicycle injuries and helmet use: a systematic review and meta-analysis. Int J Epidemiol, 46(1):278-292, 2017. doi:10.1093/ije/dyw153 Evidence: High
- [11]C. W. Runyan et al. Risk factors for fatal residential fires. N Engl J Med, 327(12):859-63, 1992. doi:10.1056/NEJM199209173271207 Evidence: Low
- [12]National Center for Health Statistics. FastStats: Accidents or Unintentional Injuries. CDC National Center for Health Statistics, 2024. Evidence: Not graded (statistics)
- [13]U.S. Fire Administration. Residential fire estimate summaries (2014-2023). U.S. Fire Administration, FEMA, 2023. Evidence: Not graded (statistics)
Every factor, one by one
One quick question each. The charts above follow your answers, and so does every other What Matters page that asks the same question.
#1Phone while driving[1]+310%
In a case-crossover study of 456 drivers hurt badly enough to go to hospital, using a phone in the ten minutes before driving went with four times the chance of crashing, checked against the drivers’ own phone records.
Do you use your phone while driving?
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
#2Heavy drinking sessions[2]≈+234%
Injury risk climbs with every drink in a single sitting: across the pooled studies, the odds of a motor vehicle crash rose 1.24 times for each extra 10 g of alcohol (under one standard drink), reaching 52 times at 120 g.
How often do you have 4+ alcoholic drinks in one sitting?
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
Among 1,478 Swedish patients referred for suspected sleep apnea, police-recorded road accidents ran at 2.45 times the rate of the general population of the same age.
Do you snore loudly or wake up gasping?
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
#4Seat belt[5]≈+156%
In US fatal crashes from 1986 to 1998, belted occupants died at 0.39 times the rate of unbelted occupants sitting in the same car, a matched comparison that holds the crash itself constant.
Do you wear a seatbelt?
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
#5Prescription opioids[6]+118%
In 18,321 fatal two-vehicle crashes on US roads, drivers who tested positive for prescription opioids had 2.18 times the odds of being the one who started the crash, independent of alcohol.
Do you take prescription opioids or sedatives?
Same number, 2 answers: The study tested drivers’ blood for prescription opioids; it did not know whether the dose was as prescribed or more.
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
#6Eyesight[7]≈+113%
In 277 older drivers with cataract followed for four to six years, those who had cataract surgery were involved in crashes at 0.47 times the rate of those who did not, after adjusting for their starting eyesight.
How well do you see day to day?
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
#7Sleep length[8]+90%
Among 6,845 drivers in a representative sample of US crashes, those who had slept 6 hours in the day before were 1.3 times as likely to have caused their crash as drivers with 7 to 9 hours, rising to 1.9 times at 5 hours, 2.9 at 4 hours and 15 times under 4.
How much sleep do you usually get?
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
#8Recreational drugs[9]+36%
Across 21 observational studies from 13 countries, driving while intoxicated on cannabis, the drug with by far the most crash research, went with 1.36 times the odds of a collision: a real but low-to-moderate excess, much smaller than alcohol’s.
Do you use recreational drugs?
Same number, 2 answers: The meta-analysis measured intoxication at the time of the crash, not how often someone uses, so regular and daily use share its figure.
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
#9Helmet[10]
Across 40 studies and over 64,000 injured cyclists, wearing a helmet in a crash or fall went with 0.35 times the odds of a fatal head injury and 0.31 times the odds of a serious one.
Do you wear a helmet when you bike, ski, or ride a motorbike or horse?
Not answered yet. Tap an option to save your answer. Saved to your quiz answers, so the quiz shows it too.
In every fatal house fire in single-family homes across North Carolina for 13 months, compared with nonfatal fires from the same period, homes with no smoke detector carried 3.4 times the odds that the fire killed someone.
Is there a working smoke alarm where you live?
Not answered yet. Tap an option to save your answer. This answer does not change your life estimate.