title: Disability weights from a household survey in a low socio-economic setting: how does it compare to the global burden of disease 2010 study?
abstract: BACKGROUND
  The global burden of disease (GBD) 2010 study used a universal set of disability weights to estimate disability adjusted life years (DALYs) by country. However, it is not clear whether these weights can be applied universally in calculating DALYs to inform local decision-making. This study derived disability weights for a resource-constrained community in Cape Town, South Africa, and interrogated whether the GBD 2010 disability weights necessarily represent the preferences of economically disadvantaged communities.
  
  
  METHODS
  A household survey was conducted in Lavender Hill, Cape Town, to assess the health state preferences of the general public. The responses from a paired comparison valuation method were assessed using a probit regression. The probit coefficients were anchored onto the 0 to 1 disability weight scale by running a lowess regression on the GBD 2010 disability weights and interpolating the coefficients between the upper and lower limit of the smoothed disability weights.
  
  
  RESULTS
  Heroin and opioid dependence had the highest disability weight of 0.630, whereas intellectual disability had the lowest (0.040). Untreated injuries ranked higher than severe mental disorders. There were some counterintuitive results, such as moderate (15th) and severe vision impairment (16th) ranking higher than blindness (20th). A moderate correlation between the disability weights of the local study and those of the GBD 2010 study was observed (R(2)=0.440, p<0.05). This indicates that there was a relationship, although some conditions, such as untreated fracture of the radius or ulna, showed large variability in disability weights (0.488 in local study and 0.043 in GBD 2010).
  
  
  CONCLUSIONS
  Respondents seemed to value physical mobility higher than cognitive functioning, which is in contrast to the GBD 2010 study. This study shows that not all health state preferences are universal. Studies estimating DALYs need to derive local disability weights using methods that are less cognitively demanding for respondents.
authors.affiliation: Burden of Disease Research Unit, South African Medical Research Council, Cape Town, South Africa; ineethli@mrc.ac.za.
authors.forename: Ian
authors.initials: I
authors.lastname: Neethling
authors.affiliation: Department of Health and Rehabilitation Sciences, University of Cape Town, Cape Town, South Africa.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Jelsma
authors.affiliation: Department of Health and Rehabilitation Sciences, University of Cape Town, Cape Town, South Africa.
authors.forename: Lebogang
authors.initials: L
authors.lastname: Ramma
authors.affiliation: School of Public Health, University of the Western Cape, Cape Town, South Africa.
authors.forename: Helen
authors.initials: H
authors.lastname: Schneider
authors.affiliation: Burden of Disease Research Unit, South African Medical Research Council, Cape Town, South Africa.
authors.forename: Debbie
authors.initials: D
authors.lastname: Bradshaw
keywords: DALY; South Africa; disability adjusted life years; disability weights; health state preferences; pairwise comparisons