Tracking search engine queries for suicide in the United Kingdom, 2004-2013

First, to determine if a cyclical trend is observed for search activity of suicide and three common suicide risk factors in the United Kingdom: depression, unemployment, and marital strain. Second, to test the validity of suicide search data as a potential marker of suicide risk by evaluating whether web searches for suicide associate with suicide rates among those of different ages and genders in the United Kingdom.

Cross-sectional.

Search engine data was obtained from Google Trends, a publicly available repository of information of trends and patterns of user searches on Google. The following phrases were entered into Google Trends to analyse relative search volume for suicide, depression, job loss, and divorce, respectively: 'suicide'; 'depression + depressed + hopeless'; 'unemployed + lost job'; 'divorce'. Spearman's rank correlation coefficient was employed to test bivariate associations between suicide search activity and official suicide rates from the Office of National Statistics (ONS).

Cyclical trends were observed in search activity for suicide and depression-related search activity, with peaks in autumn and winter months, and a trough in summer months. A positive, non-significant association was found between suicide-related search activity and suicide rates in the general working-age population (15-64 years) (ρ = 0.164; P = 0.652). This association is stronger in younger age groups, particularly for those 25-34 years of age (ρ = 0.848; P = 0.002).

We give credence to a link between search activity for suicide and suicide rates in the United Kingdom from 2004 to 2013 for high risk sub-populations (i.e. male youth and young professionals). There remains a need for further research on how Google Trends can be used in other areas of disease surveillance and for work to provide greater geographical precision, as well as research on ways of mitigating the risk of internet use leading to suicide ideation in youth.