Frequency of true adverse reactions to measles-mumps-rubella vaccine. A double-blind placebo-controlled trial in twins

Lancet. 1986 Apr 26;1(8487):939-42. doi: 10.1016/s0140-6736(86)91044-5.


The vast majority of adverse reactions following immunisation of children with live measles-mumps-rubella (MMR) vaccine were shown in a double-blind, placebo-controlled, cross-over study in 581 twin pairs to be only temporally but not causally related to the vaccination. The true frequency of side-effects caused by MMR vaccine, estimated from the discordance rates of individual signs and symptoms between MMR vaccinees and their placebo-injected twins, was between 0.5 and 4.0%. Moreover, respiratory symptoms, nausea, and vomiting were observed more frequently in the placebo-injected group than in the MMR vaccinated group.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Child
  • Child, Preschool
  • Clinical Trials as Topic
  • Double-Blind Method
  • Female
  • Fever / etiology
  • Humans
  • Infant
  • Male
  • Measles Vaccine / administration & dosage
  • Measles Vaccine / adverse effects*
  • Mumps Vaccine / administration & dosage
  • Mumps Vaccine / adverse effects*
  • Rubella Vaccine / administration & dosage
  • Rubella Vaccine / adverse effects*
  • Surveys and Questionnaires
  • Time Factors
  • Twins
  • Vaccination / methods


  • Measles Vaccine
  • Mumps Vaccine
  • Rubella Vaccine