Figure 1

Estimation of the number of fall detection studies. We have made a longitudinal study of published papers, classifying the detection techniques into three categories. The line graph (associated with the right axis) represents the estimated absolute number of studies published in the three categories from 2005 to 2012. The bar graph (associated with the left axis) shows the estimated percentage of studies published every year in relation to the total number of existing studies for each category (e.g., 43.3% of the existing smartphone-based studies were published in 2012).