Study registration: *
Publication Patalon T, medRxiv, 2021
Dates: 2021-01-01 to 2021-08-21
Funding: Public/non profit (NIAID of the National Institutes of Health.)
Conflict of interest: Yes (DMW has received consulting fees from Pfizer, Merck, Affinivax, and Matrivax for work unrelated to this paper and is Principal Investigator on grants from Pfizer and Merck to Yale University for work unrelated to this manuscript. VEP has received reimbursement from Merck and Pfizer for travel to Scientific Input Engagements unrelated to the topic of this manuscript and is a member of the WHO Immunization and Vaccine-related Implementation Research Advisory Committee (IVIR-AC). JW discloses consulting fees from Revelar Inc.)
Description of participants: Aged 40 and up Maccabi Healthcare Services members in multiple centres in Israel
Follow-up duration (months): 7.73
|Variant description :
Variant name: Delta|
Evidence: Indirect evidence (prevalence of variant in the population: *)
The preprint was used in data extraction and risk of bias assessment. Results were extracted for the longest follow up time, which was 14-20 days after booster. Prevalence of Delta variant was not reported, but states it was the dominant strain in Israel.
Concerns over uncontrolled confounding. We have concerns due to the use of a test-negative design and a lack of a statistical analysis plan.