Background The Huntington’s disease quality of life questionnaire (HDQoL) is a disease specific measure of the impact of Huntington’s disease on everyday life as reported by patients.
Aim The current study aimed to use the HDQol subscales to predict generic quality of life measures commonly used.
Method Using data from an initial sample of one hundred and fifty two participants who completed the HDQoL, the SF-12 and EQ-5D questionnaires, linear regressions were carried out with EQS 5-D index score, SF12 Physical Component Score (PCS) and SF12 Mental Component Score (MCS) as dependent variables. The predictors were either the three HDQol Primary Scales (Physical and Cognitive, Emotions and Self, Services), or the six HDQol Specific Scales (Physical and Functional, Cognitive, Hopes and Worries, Mood State, Self and Vitality, Services).
Results For EQS 5-D index score, the regression using the 3 primary scale predictors yielded an R 2 of 0.61, with all 3 predictors being individually significant. The regression with the 6 specific scale predictors yielded an R 2 of 0.66, with four specific scales (Physical and Functional, Cognitive, Mood State, Self and Vitality) being individually significant. For SF12 PCS and the 3 primary scale predictors, R 2 was 0.63, with all the variables significant; with the 6 specific scale predictors, R 2 = 0.66, only Physical and Functional and Services were individually significant. For SF12 MCS and the 3 primary scale predictors, R 2 = 0.56: only Emotions and Self was individually significant. With the 6 specific scale predictors, R 2 = 0.58, with Mood State, Self and Vitality, Cognitive, and Physical and Functional scales being individually significant.
Conclusion Across all the analyses, R 2 ranged from 0.56 to 0.66, indicating that the HDQoL scales provide reasonable predictions of general EQ-5D and SF12 scales.