The stability of impact of assistive devices. 
Abandonment of an assistive device (AD) is a frustrating issue yet is very common.  An important reason for abandonment is that the device fails to improve the quality of life of the adopter.  By means of a new questionnaire, the Psychosocial Impact of Assistive Devices Scale (PIADS) the impact on quality of life of any AD can be measured.  This study tested the hypothesis that the impact of the adoption of an AD would wane with time, as the user becomes more adapted to the AD.  The study attempted to do a one year follow up on all patients at a leading Canadian clinic who had received first-time prescriptions for eyeglasses.  The results showed that the positive impact, present on adoption, did not diminish significantly for those who retained the use of the device.  The PIADS provides clinicians with a reliable and economical method for assessing the role of psychosocial factors in the retention or abandonment of an AD.