Do interventions that improve immunisation uptake also reduce social inequalities in uptake?
OBJECTIVE
To investigate whether an intervention designed to improve overall immunisation uptake affected social inequalities in uptake.


METHODS
Cross-sectional small area analyses measuring immunisation uptake in cohorts of children before and after intervention. Small areas classified into five groups, from most deprived to most affluent, with Townsend deprivation score of census enumeration districts.


METHODS
County of Northumberland.


METHODS
All children born in country in four birth cohorts (1981-2, 1985-6, 1987-8, and 1990-1) and still resident at time of analysis.


METHODS
Overall uptake in each cohort of pertussis, diphtheria, and measles immunisation, difference in uptake between most deprived and most affluent areas, and odds ratio of uptake between deprived and affluent areas.


RESULTS
Coverage for pertussis immunisation rose from 53.4% in first cohort to 91.1% in final cohort. Coverage in the most deprived areas was lower than in the most affluent areas by 4.7%, 8.7%, 10.2%, and 7.0% respectively in successive cohorts, corresponding to an increase in odds ratio of uptake between deprived and affluent areas from 1.2 to 1.6 to 1.9 to 2.3. Coverage for diphtheria immunisation rose from 70.0% to 93.8%; differences between deprived and affluent areas changed from 8.6% to 8.3% to 9.0% to 5.5%, corresponding to odds ratios of 1.5, 2.0, 2.5, and 2.6. Coverage for measles immunisation rose from 52.5% to 91.4%; differences between deprived and affluent areas changed from 9.1% to 5.7% to 8.2% to 3.6%, corresponding to odds ratios of 1.4, 1.4, 1.7, and 1.5.


CONCLUSIONS
Despite substantial increase in immunisation uptake, inequalities between deprived and affluent areas persisted or became wider. Any reduction in inequality occurred only after uptake in affluent areas approached 95%. Interventions that improve overall uptake of preventive measures are unlikely to reduce social inequalities in uptake.
Reading
R
R
Jenny Lind Department, Norwich and Norfolk Hospital.
Colver
A
A
Openshaw
S
S
Jarvis
S
S
D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004165:Diphtheria / Q000517:prevention & control; D004739:England; D006293:Health Promotion; D006801:Humans; D017589:Immunization Programs / Q000706:statistics & numerical data*; D007223:Infant; D007231:Infant, Newborn; D008457:Measles / Q000517:prevention & control; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data*; D011203:Poverty; D017062:Small-Area Analysis; D012923:Social Class; D014917:Whooping Cough / Q000517:prevention & control