The SEIQoL-DW for assessing quality of life in ALS: Strengths and limitations

The Schedule for the Evaluation of the Individual Quality of Life-Direct Weighting (SEIQoL-DW) has been used to measure quality of life (QoL) in small cohorts of individuals with ALS, but its suitability for assessing aggregate QoL for between-group comparisons is uncertain. We undertook a prospective study in which 120 patients with ALS completed two measures of QoL, the SEIQoL-DW and the McGill Quality of Life Single-Item Scale (MQoL-SIS). There was a weak correlation between the SEIQoL-DW index score and the MQoL-SIS. Only three of five cues accounted for a significant amount of variance in the MQoL-SIS, and even those accounted for only 12.8%-13.9% of the variance. Cues relating to family or significant other were chosen by over 90% of patients, and were the most heavily weighted. This study demonstrates that the SEIQoL-DW is of great value in identifying those factors which contribute to the psychosocial wellbeing of an individual with ALS. However, SEIQoL index scores may not reflect aggregate QoL of groups of patients with ALS, and may be measuring a construct other than QoL. Caution should be exercised in using the SEIQoL index score to measure QoL of groups, such as would be needed in interventional trials.