Characterization of working and mobile phone usage distances in common users of electronic devices and computers

AIM: To analyse and characterize the pattern of working and mobile phone usage distances for common users of electronic devices and computers. METHODS: Transversal descriptive study consisting of a screening campaign evaluating the visual status of different professionals working with computers or electronic devices more than 2h per day. A total of 100 healthy patients with a mean age of 41.2 (range: 20-62) years were revised and subdivided according to job subgroups. A battery of screening tests was performed to all participants in a single session at the working environment of each of them, including measurement of the working distance (WD), arm length, and mobile phone usage distances (MPUD). RESULTS: The WD was significantly longer than MPUD (61.22±12.35 vs 32.22±6.35 cm; P<0.001). Likewise, MPUD was significantly shorter than the arm length (74.44±4.65 cm; P<0.001). A total of 4% (4/100) and 91% (91/100) of patients had a WD and MPUD of 40 cm or below, respectively. A weak although statistically significant correlation was found between WD and MPUD (r=0.387, P<0.001) as well as between WD and arm length (r=0.260, P=0.009). Statistically significant differences were detected among job subgroups in WD (P=0.021), being longer for militaries compared to university researchers and lecturers (P=0.025). CONCLUSION: Working and mobile phone usage distances vary significantly among common users of computers and digital devices, although the use of mobile phones tends to be performed at significantly closer distances. This parameter should be considered when planning any type of optical correction, especially for presbyopia.