Population health concerns during the United States' Great Recession.
BACKGROUND
Associations between economic conditions and health are usually derived from cost-intensive surveys that are intermittently collected with nonspecific measures (i.e., self-rated health).


OBJECTIVE
This study identified how precise health concerns changed during the U.S. Great Recession analyzing Google search queries to identify the concern by the query content and their prevalence by the query volume.


METHODS
Excess health concerns were estimated during the Great Recession (December 2008 through 2011) by comparing the cumulative difference between observed and expected (based on linear projections from pre-existing trends) query volume for hundreds of individual terms. As performed in 2013, the 100 queries with the greatest excess were ranked and then clustered into themes based on query content.


RESULTS
The specific queries with the greatest relative excess were stomach ulcer symptoms and headache symptoms, respectively, 228% (95% CI=35, 363) and 193% (95% CI=60, 275) greater than expected. Queries typically involved symptomology (i.e., gas symptoms) and diagnostics (i.e., heart monitor) naturally coalescing into themes. Among top themes, headache queries were 41% (95% CI=3, 148); hernia 37% (95% CI=16, 142); chest pain 35% (95% CI=6, 313); and arrhythmia 32% (95% CI=3, 149) greater than expected. Pain was common with back, gastric, joint, and tooth foci, with the latter 19% (95% CI=4, 46) higher. Among just the top 100, there were roughly 205 million excess health concern queries during the Great Recession.


CONCLUSIONS
Google queries indicate that the Great Recession coincided with substantial increases in health concerns, hinting at how population health specifically changed during that time.
Santa Fe Institute, Santa Fe, New Mexico.
Benjamin M
BM
Althouse
Keck School of Medicine, University of Southern California, Los Angeles.
Jon-Patrick
JP
Allem
School of Public and International Affairs, University of Georgia, Athens, Georgia.
Matthew A
MA
Childers
Human Language Technology Center of Excellence, Johns Hopkins University Baltimore, Maryland.
Mark
M
Dredze
Graduate School of Public Health, San Diego State University, San Diego, California. Electronic address: ayers.john.w@gmail.com.
John W
JW
Ayers
D002637:Chest Pain / Q000453:epidemiology; D015331:Cohort Studies; D057172:Economic Recession / Q000706:statistics & numerical data / Q000639:trends*; D006261:Headache / Q000175:diagnosis / Q000453:epidemiology*; D006547:Hernia / Q000453:epidemiology; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data; D011159:Population Surveillance / Q000379:methods*; D013276:Stomach Ulcer / Q000175:diagnosis / Q000453:epidemiology*; D014481:United States / Q000453:epidemiology