title: Ethnic differences in asthma treatment among Swedish adolescents: A multilevel analysis of individual heterogeneity.
abstract: OBJECTIVE
  Adolescents with immigrant or ethnic minority background suffering from asthma receive on average less appropriate anti-asthmatic medication (AAM) than the majority population. However, those findings are based on analyses of differences between group averages which prevents our understanding of individual heterogeneity around the averages. Taking into account individual socioeconomic factors and medical needs, we performed multilevel analysis in order to evaluate if maternal country of birth (MCOB) accurately identifies adolescents with inappropriate AAM use.
  
  
  METHODS
  Using the Swedish Medical Birth Register, we identified all singleton children born between 1988 and 1991 who were residing in the country until they turned 17 and had complete information on the study variables. We applied a two-level multilevel logistic regression analysis with 62 MCOBs at the second and 755,894 children at the first level. Adjusting for socioeconomic and medical factors using a risk score, and including the socioeconomic characteristics of the MCOBs, we obtained both measures of association (odds ratio (OR)) and measures of variance (Intra-class correlation (ICC)).
  
  
  RESULTS
  Comparing with adolescents born from Swedish mothers, all other children had a lower AAM use, especially those whose mothers were from upper-middle- and low-income countries (OR = 0.47, 95% confidence interval: 0.35-0.61). However, the ICC was low (i.e., ICC ≈ 3%) for both preventive and relief AAM.
  
  
  CONCLUSIONS
  MCOB was associated to adolescent use of AAM. However, the small ICC indicates that MCOB is an inaccurate categorization for identifying inappropriate use of AAM among Swedish adolescents.
authors.affiliation: Faculty of Health and Medical Sciences, Department of Pharmacy, Section for Social and Clinical Pharmacy, University of Copenhagen, Denmark Faculty of Medicine, Unit for Social Epidemiology, Lund University, Malmö, Sweden lou.cantarero@sund.ku.dk.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Cantarero-Arévalo
authors.affiliation: Faculty of Medicine, Unit for Social Epidemiology, Lund University, Malmö, Sweden.
authors.forename: Raquel
authors.initials: R
authors.lastname: Perez Vicente
authors.affiliation: Faculty of Medicine, Unit for Social Epidemiology, Lund University, Malmö, Sweden Centrum for Economic Demography, Lund, Sweden.
authors.forename: Sol Pia
authors.initials: SP
authors.lastname: Juarez
authors.affiliation: Faculty of Medicine, Unit for Social Epidemiology, Lund University, Malmö, Sweden.
authors.forename: Juan
authors.initials: J
authors.lastname: Merlo
mesh_terms: D000293:Adolescent; D000328:Adult; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use*; D001249:Asthma / Q000188:drug therapy* / Q000208:ethnology*; D054242:Emigrants and Immigrants / Q000706:statistics & numerical data*; D005260:Female; D054625:Healthcare Disparities / Q000208:ethnology*; D006801:Humans; D008297:Male; D009035:Mothers / Q000706:statistics & numerical data; D055361:Multilevel Analysis; D012959:Socioeconomic Factors; D013548:Sweden; D055815:Young Adult
chemical_list: D018927:Anti-Asthmatic Agents
keywords: Children; Sweden; asthma medication; ethnic minority group; multilevel analysis; pharmacoepidemiology