title: Differences in risk factors for partial and no immunisation in the first year of life: prospective cohort study.
abstract: OBJECTIVE
  To compare demographic, social, maternal, and infant related factors associated with partial immunisation and no immunisation in the first year of life in the United Kingdom.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Sample of electoral wards in England, Wales, Scotland, and Northern Ireland, stratified by measures of ethnic composition and social disadvantage.
  
  
  METHODS
  18,488 infants born between September 2000 and January 2002, resident in the UK and eligible to receive child benefit (a universal benefit available to all families) at age 9 months.
  
  
  METHODS
  Immunisation status at 9 months of age, defined as fully immunised, partially immunised, or not immunised.
  
  
  RESULTS
  Overall in the UK, 3.3% of infants were partially immunised and 1.1% were unimmunised; these rates were highest in England (3.6% and 1.3%, respectively; P < 0.01). Residence in ethnic or disadvantaged wards, larger family size, lone or teenaged parenthood, maternal smoking in pregnancy, and admission to hospital by 9 months of age were independently associated with partial immunisation status. In contrast, a higher proportion of mothers of unimmunised infants were educated to degree level or above (1.9%), were older (3.1%), or were of black Caribbean ethnicity (4.7%).
  
  
  CONCLUSIONS
  Mothers of unimmunised infants differ in terms of age and education from those of partially immunised infants. Interventions to reduce incomplete immunisation in infancy need different approaches.
authors.affiliation: Centre for Paediatric Epidemiology and Biostatistics, Institute of Child Health, 30 Guilford Street, London WC1N 1EH.
authors.forename: Lamiya
authors.initials: L
authors.lastname: Samad
authors.forename: A Rosemary
authors.initials: AR
authors.lastname: Tate
authors.forename: Carol
authors.initials: C
authors.lastname: Dezateux
authors.forename: Catherine
authors.initials: C
authors.lastname: Peckham
authors.forename: Neville
authors.initials: N
authors.lastname: Butler
authors.forename: Helen
authors.initials: H
authors.lastname: Bedford
mesh_terms: D000367:Age Factors; D001294:Attitude to Health; D015331:Cohort Studies; D004522:Educational Status; D005191:Family Characteristics; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007114:Immunization / Q000706:statistics & numerical data*; D007223:Infant; D009035:Mothers / Q000523:psychology; D011203:Poverty / Q000706:statistics & numerical data; D011446:Prospective Studies; D012307:Risk Factors; D020954:Single-Parent Family / Q000706:statistics & numerical data; D012907:Smoking / Q000453:epidemiology; D006113:United Kingdom / Q000453:epidemiology