Data underlying the publication "Comfort and Discomfort in a Chair Using the Smartphone".

This paper presents the results of an experiment studying the effect of using an arm support on smartphone use. Twenty-four participants tested a chair with a special arm support for smartphone use. The participants were asked by questionnaire to describe their perception of their comfort and discomfort after they used the chair with and without the armrest for 15 minutes. The effects on posture and productivity were tested. Productivity was tested by counting the number of typed characters and spelling mistakes. There was a nonsignificant trend that the word count of users in the smartphone chair without the armrest was higher than with armrest and the spelling mistakes of users in the chair without armrests were lower than in the seat with armrests (p< 0.05). Comfort and discomfort were evaluated using a questionnaire. The discomfort and comfort differed for the total body, neck, upper back, lower back, lower arm, wrist and leg, but not significantly. Only the upper arm in the condition with arm support showed a higher discomfort and a lower comfort level (p< 0.05). The posture of the participants was analysed using Kinovea software for the body angles and were processed further using a RULA assessment. The results show that the potential ergonomic risk when people used the smartphone in the chair without arm support is lower than when they used the chair with the armrest (p< 0.05). In conclusion, the armrest increased discomfort of the upper arm of participants, probably because it limits freedom of movement or because the height of the armrest is not adjustable.