Lone parent families are an independent risk factor for lower rates of childhood immunisation in London.

The aim of this study was to determine associations between indicators of social deprivation and the uptake of primary immunisation in London. Correlation coefficients were calculated between immunisation coverage in London for each of the 28 inner and outer London district health authorities in November 1991 and a range of possible explanatory variables from small area statistics data from the November 1991 census. The proportions of children under 5 years of age, lone parent families, unemployed members of the workforce, domestic overcrowding, ethnic minorities, and unskilled workforce were correlated significantly with the coverage of primary immunisation for third dose diphtheria (D3) and pertussis (P3) at 12 months. A significant correlation with measles, mumps, and rubella (MMR) at 24 months existed only for lone parent families. Multiple linear regression weighted by population size was used to identify independent predictors of variation in immunisation cover. The proportion of lone parent families in each district health authority was the only significant independent risk factor consistently associated with variation in immunisation coverage for D3, P3, and MMR. The proportion of lone parent families explained 42% of the variation in coverage for D3 in November 1991. This study has identified lone parenthood as an important independent risk factor in London for failure to complete immunisation.