Analysis of ear side of mobile phone use in the general population of Japan.

This study aimed to clarify the distribution of the ear side of mobile phone use in the general population of Japan and clarify what factors are associated with the ear side of mobile phone use. Children at elementary and junior high schools (n = 2,518) and adults aged ≥20 years (n = 1,529) completed an Internet-based survey. Data were subjected to a logistic regression analysis. In children, due to the tendency to use the dominant hand, we analyzed the factors associated with the use of right ear in right-handed people. Statistically significant differences were observed only in talk time per call (odds ratio (OR) = 2.17; 95% confidence interval (CI): 1.22-3.99). In adults, due to the tendency to use the left ear, we analyzed factors associated with the use of left ear in right-handed people. Significant differences were observed in those aged 30-39 years (OR = 2.55; 95% CI: 1.79-3.68), those aged 40-49 years (OR = 3.08; 95% CI: 2.15-4.43), those aged >50 years (OR = 1.85; 95% CI: 1.20-2.85), and in those with a percentage of total talk time when using mobile phones at work of 51-100% (OR = 1.75; 95% CI: 1.21-2.55). We believe that future epidemiological studies on mobile phone use can be improved by considering the trends in mobile phone use identified in this study. Bioelectromagnetics. 39:53-59, 2018. © 2017 Wiley Periodicals, Inc.