IRCT2014113020142N2 IRCT 2014-12-25 Shiraz University of Medical Sciences Posture and comfort evaluation in computer users posture assessment and comfort measurement while working with different types of computer input devices 2014-06-21 anticipated 21 Complete https://irct.ir/trial/17870 interventional Randomization: N/A, Blinding: Not blinded, Placebo: Not used, Assignment: Single, Purpose: Prevention. N/A Soft tissue disorders. The intervention is change of computer input device. All subjects experience all interventions. In the lab before the onset of the experiment, each subject complete a demographic questionnaire. Then, the first computer input device is randomly selected and the subject is asked to work with it and do a defined standard task for 15 minutes. During this time the postural angles are measured. After this stage, there is a 10-minute rest time when the subject is asked to judge about working condition and comfort of working with the device. After this period of rest, the second trial begins under identical condition. In this stage, the subject work with the second randomly selected device and do the standard task for 15 minutes and the same procedure is repeated until the third device is also worked with..