title: Internet monitoring of suicide risk in the population.
abstract: BACKGROUND
  Public health statistics are often released too late to affect reversible societal factors affecting suicide. Increasingly, internet search volume is used in epidemiology, but this method has not yet been applied to suicide.
  
  
  METHODS
  Google internet search engine activity for suicide-related terms from the years 2004-2009 was measured and correlated to available suicide and intentional self-injury data from the Centers of Disease Control (CDC).
  
  
  RESULTS
  Google search volumes correlated to CDC statistics for both suicide and self-injury, but in patterns that differed by age. Whereas internet search activity was negatively correlated to the suicide rate in the general population, it was positively correlated to both intentional self-injury and completed suicides among youth.
  
  
  CONCLUSIONS
  Monitoring changes in search volumes on the internet may provide an early indicator of suicide risk within the population. Furthermore, youth may utilize the internet in ways that differ from the general population with respect to suicide.
authors.affiliation: Department of Psychiatry, University of California, San Diego, La Jolla, CA 92093, United States of America. mmccarthy@ucsd.edu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: McCarthy
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000523:psychology*; D002487:Centers for Disease Control and Prevention, U.S.; D005260:Female; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D057386:Search Engine; D016728:Self-Injurious Behavior / Q000453:epidemiology* / Q000523:psychology; D013405:Suicide / Q000523:psychology / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology; D055815:Young Adult