J S Wolffsohn1, A L Cochrane, N A Watt. 1. Victorian College of Optometry, University of Melbourne, Victoria, Australia. j.s.wolffsohn@aston.ac.uk
Abstract
AIM: To determine the most reliable and consistent method and time interval over which to implement a vision impairment quality of life assessment tool. METHODS: 117 patients with low vision aged 9-101 years were assigned into three age, sex, and visual function matched groups (n = 39 in each) to answer the Low Vision Quality of Life (LVQOL) questionnaire by post, telephone, or in person. The LVQOL questionnaire was completed on four occasions, each separated by four weeks. RESULTS: Postal implementation was the most cost effective method, showed the highest internal consistency of LVQOL items, but resulted in a lower apparent quality of life score than either telephone or in-person interviews (p<0.001). There was no difference in test-retest reliability between the three methods of implementation (p = 0.12). The profile of LVQOL scores showed a trend towards reduced quality of life scores 3 months after the baseline measures, although this was not significant. CONCLUSION: Posting may be the method of choice for clinical measurement of vision related quality of life. Patients with greater visual impairment were no less likely to complete a questionnaire when implemented by post and there was no apparent bias from other people assisting them. The quality of life measure can occur at any time up to 2 months after low vision rehabilitation for the progressive nature of conditions causing low vision not to cause a decreased baseline score. The LVQOL was shown to be a highly internally consistent and reliable method for measuring quality of life in the visually impaired.
AIM: To determine the most reliable and consistent method and time interval over which to implement a vision impairment quality of life assessment tool. METHODS: 117 patients with low vision aged 9-101 years were assigned into three age, sex, and visual function matched groups (n = 39 in each) to answer the Low Vision Quality of Life (LVQOL) questionnaire by post, telephone, or in person. The LVQOL questionnaire was completed on four occasions, each separated by four weeks. RESULTS: Postal implementation was the most cost effective method, showed the highest internal consistency of LVQOL items, but resulted in a lower apparent quality of life score than either telephone or in-person interviews (p<0.001). There was no difference in test-retest reliability between the three methods of implementation (p = 0.12). The profile of LVQOL scores showed a trend towards reduced quality of life scores 3 months after the baseline measures, although this was not significant. CONCLUSION: Posting may be the method of choice for clinical measurement of vision related quality of life. Patients with greater visual impairment were no less likely to complete a questionnaire when implemented by post and there was no apparent bias from other people assisting them. The quality of life measure can occur at any time up to 2 months after low vision rehabilitation for the progressive nature of conditions causing low vision not to cause a decreased baseline score. The LVQOL was shown to be a highly internally consistent and reliable method for measuring quality of life in the visually impaired.
Authors: James Stuart Wolffsohn; Jonathan Jackson; Olivia Anne Hunt; Charles Cottriall; Jennifer Lindsay; Richard Gilmour; Anne Sinclair; Robert Harper Journal: Int J Ophthalmol Date: 2014-02-18 Impact factor: 1.779
Authors: Jan Mitchell; James S Wolffsohn; Alison Woodcock; Stephen J Anderson; Carolyn V McMillan; Timothy Ffytche; Martin Rubinstein; Winfried Amoaku; Clare Bradley Journal: Health Qual Life Outcomes Date: 2005-04-14 Impact factor: 3.186