Measuring quality of life of patients with axial spondyloarthritis for economic evaluation.

OBJECTIVES: To estimate the relationship between EQ5D (three levels, UK version) and the Ankylosing Spondylitis Disease Activity Score (ASDAS) for use in the economic evaluation of health technologies for people with axial spondyloarthritis (axSpA). To compare against the relationship with the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). METHODS: An electronic, prospective, Portuguese, nationwide, rheumatic disease register (Reuma.pt) provided data on 1140 patients (5483 observations) with a confirmed diagnosis of axSpA. We estimated models of EQ5D as a function of ASDAS, alone or in combination with measures of functional impairment, using bespoke mixture models which reflect the complex distributional features of EQ5D. The SPondyloArthritis Caught Early cohort provided data from 344 patients (1405 observations) in four European countries and was used for validation. A previously published model of BASDAI/Bath Ankylosing Spondylitis Functional Index (BASFI) was also used to generate predicted EQ5D scores and model performance compared. RESULTS: A non-linear relationship exists between EQ5D from ASDAS. The final model included ASDAS, ASDAS squared, age and age squared and demonstrated close fit in both datasets except where data were sparse for patients with very high levels of disease activity (ASDAS >4). This finding held in the validation dataset. Models that included BASFI improved model fit. The ASDAS based models fit the data marginally less well than models using BASDAI. CONCLUSIONS: Mapping models linking ASDAS to EQ5D allow results from clinical studies to be used in economic evaluation of health technologies with confidence. There is some loss of information compared with BASDAI but this has only a marginal impact.

Protecting the mental health of future adults: Disentangling the determinants of adolescent bullying victimisation.

BACKGROUND: Adolescent bullying victimisation and maltreatment have been linked to mental health disorders. Early intervention interrupting victimisation continuity is required since adolescence is a critical period for the formation of adult skills. We investigate the protective factors against youth victimisation at school and domestically. METHOD: This study uses the youth self-completion questionnaire (preadolescents/adolescents aged 10-15) from the UK Household Longitudinal Study (UKHLS) containing youth victimisation questions in waves 1, 3 and 5 spanning 2009-2013. The self-reported victimisation measures include direct aggression (physical, verbal) and indirect bullying by other young people at school/non-domestically and at the household. The investigation employs balanced and unbalanced sample designs, complete case analysis (CCA) and multiple imputation (MI). RESULTS: The most effective protective factor reducing victimisation at school and domestically is the strength of family support as felt by the child (perceived family support) and the quality of the family environment. The unobserved factors increasing non-domestic victimisation are related to the latent factors reducing family support. This indicates that victimised adolescents do not always inform their families. The intensity of past period bullying is a strong predictor of future victimisation. CONCLUSIONS: The importance of family support and the quality of the family environment as protective factors necessitates parental involvement in school anti-bullying programmes. The longitudinal persistence of bullying indicates the inability of frequently bullied adolescents to escape victimisation. Anti-bullying policy design should encourage victims to speak up by lowering victimisation stigma and, provide assurances against bully retaliation.