“…Several other possible passive data collection methods have been examined in the literature, including internet death notices as a source of mortality surveillance data (Boak, M'Ikanatha, Day, & Harrison, 2008), forum postings (Kate, Negi, & Kalagnanam, 2014;Weitzman, Adida, Kelemen, & Mandl, 2011) and restaurant reviews and reservations (Harrison et al, 2014;Nsoesie, Kluberg, & Brownstein, 2014;Nsoesie, Buckeridge, & Brownstein, 2014)…”