Study type

Study topic

Disease /health condition
Human medicinal product

Study type

Non-interventional study

Scope of the study

Assessment of risk minimisation measure implementation or effectiveness
Disease epidemiology

Data collection methods

Secondary data collection
Non-interventional study

Non-interventional study design

Cohort
Study drug and medical condition

Anatomical Therapeutic Chemical (ATC) code

(J07CA02) diphtheria-pertussis-poliomyelitis-tetanus

Medical condition to be studied

Thrombocytopenia
Thrombocytopenic purpura
Population studied

Short description of the study population

The study population included general population and patients visiting general practices identified from the IMRD databases.

Age groups

Term newborn infants (0 – 27 days)
Infants and toddlers (28 days – 23 months)
Children (2 to < 12 years)
Adolescents (12 to < 18 years)
Adults (18 to < 46 years)
Adults (46 to < 65 years)
Adults (65 to < 75 years)
Adults (75 to < 85 years)
Adults (85 years and over)

Estimated number of subjects

200000
Study design details

Main study objective

Describe: • How the diphtheria / tetanus / pertussis (acellular, component) / poliomyelitis (inactivated) vaccines (DTaP-IPV or TdaP-IPV) were used in the general population? • How has use of the vaccine changed with time? • What was the event rate of immune thrombocytopenia in the general population? • What was the event rate in the population exposed to the vaccine?

Data analysis plan

A cohort study describing vaccine exposure, population incidence rates of immune thrombocytopenia, and (where possible) incidence rates of immune thrombocytopenia in the vaccine exposed population. Vaccine exposure was described as counts of patients with a first exposure stratified by age, sex, and year of general practice visit. Incidence of new onset immune thrombocytopenia in all patients contributing patient time to the databases, excluding those with any prior history of any of the selected codes for thrombocytopenia in the database, and then restricting to only those patients known to have been exposed to the vaccine. Follow up time (years) = ((end date for the period – start date for the period + 1))/365, Incidence rate = (number of new onset events)/(total follow up time (years)). Incidence is presented as the number of events per 100,000 person-years, calculated for the entire population as well as stratified by year, gender, and age group.
Documents
Study results

FINAL Report_Immune thrombocytopenia_20220909_for publication_CLEAN

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