Study type

Study topic

Human medicinal product
Disease /health condition

Study type

Non-interventional study

Scope of the study

Assessment of risk minimisation measure implementation or effectiveness

Data collection methods

Secondary use of data
Non-interventional study

Non-interventional study design

Cohort
Study drug and medical condition

Anatomical Therapeutic Chemical (ATC) code

(J07BX) Other viral vaccines
Other viral vaccines

Medical condition to be studied

Thrombosis with thrombocytopenia syndrome
Venous thrombosis
Population studied

Short description of the study population

All adult persons (aged >=18 at the index date) registered in any of the contributing databases within the study period and with at least one year of database history before the index date will be included in the target population.

Age groups

  • 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

80000000
Study design details

Main study objective

1) To study the association between COVID-19 vaccine and thrombosis with thrombocytopenia syndrome/s (TTS) and thromboembolic events (VTE) 2) To quantify the association betweendifferent COVID-19 vaccine brands and the occurrence of TTS /VTE 3) To study the association between pre-specified risk factors and the occurrence of VTE/TTS 4) To characterize treatments used after post-vaccine VTE/TTS

Outcomes

VTE thrombosis with thrombocytopenia syndrome

Data analysis plan

characters The study period will cover from Dec 2020 (first vaccine users) until the latest data release available in each of the contributing databases. For objective 1a-2b, we will use propensity-score-matching to select comparable people in each two cohorts. We will report incidence rates of TTS or TE in the 14, 21 and 28 days following the index date in each PS matched cohort. Incidence Rate ratio (IRR) will be used to quantify the risk of developing TTS (Objective 1) or TE (Objective 2) via Poisson models. RRs will be stratified by 10-year age bands, sex, and vaccine type/brand (only for Objective 1a and 2a). Logistic regression will be used to identify risk factors associated with TTS/VTE/ATE among people vaccinated against SARS-CoV-2.