Childhood immunisation schedules and hesitancy — KFP-style written assessment

KFP 1 (10 marks)

A mother brings her 13-month-old for MMR but refuses it: 'I read the Danish study — 6,517 kids got autism after the vaccine. And there are too many shots now anyway; her immune system can't cope.' The child is well, growing normally. ^{[1] [5]}

1. What did the Danish nationwide cohort actually measure and find? (4) ^[1]
2. Answer the 'too many too soon' claim directly with data. (3) ^[5]
3. Name two communication strategies that outperform confrontation with hesitant parents. (3) ^[10]

Model answers

1. Hviid's nationwide cohort followed all Danish children born 1999-2010: across 5,025,754 person-years, 6,517 children were diagnosed with autism (incidence 129.7 per 100,000 person-years). The fully adjusted hazard ratio for autism comparing MMR-vaccinated with unvaccinated children was 0.93 (95% CI 0.85-1.02) — no increased risk — consistent across subgroups including children with sibling autism history. She has inverted the study's finding. ^[1]
2. The direct test of immune overload is DeStefano's case-control study: cumulative antibody-stimulating antigen exposure through ages 3 months, 7 months and 2 years showed adjusted odds ratios ~0.999 per 25-unit increase — no relationship to ASD at any exposure level. Modern schedules contain fewer antigens than those of the 1990s despite covering more diseases. ^[5]
3. Presumptive announcement ('we have her vaccines due today') rather than permission-seeking; motivational interviewing that explores her specific concern before data; structured clinician training measurably improves knowledge of adverse effects and attitudes toward resistance. Keep the door open — hesitancy is a spectrum, not a verdict. ^[10]