Search reports, ask a question, or jump to a page.
The problem
Intervention: COVID-19 vaccination
Who it was tested with: Seven-year-old children from the 2015 Pelotas Birth Cohort in Brazil (n=2956).
The same group is measured before the intervention and again afterwards, with a baseline and an endline and sometimes a midline. Change is visible, but other causes cannot be ruled out.
"we examine the association between COVID-19 vaccination and antibody titer and whether this association varies by nutritional status and duration of school attendance using linear regression models applied to seven-year-old children from the 2015 Pelotas (Brazil) Birth Cohort". The study uses a prospective birth cohort with measured outcomes but lacks a comparison group randomization, making it a pre-post observational design.
Observational design cannot prove causation; cross-sectional measurement of antibody titers does not show clinical protection or infection prevention; lacks information on vaccination timing relative to natural infection exposure.
Across countries and designs
12 studies · 12 countries
