Evaluating the Quality of Studies Assessing COVID-19 Vaccine Neutralizing Antibody Immunogenicity

Objective: COVID-19 vaccine-neutralizing antibodies provide early data on potential vaccine effectiveness, but their usefulness depends on study reliability and reporting quality. Methods: We systematically evaluated 50 published post-vaccination neutralizing antibody studies for key parameters that determine study and data quality regarding sample size, SARS-CoV-2 infection, vaccination regimen, sample collection period, demographic characterization, clinical characterization, experimental protocol, live virus and pseudo-virus details, assay standardization, and data reporting. Each category was scored from very high to low or unclear quality, with the lowest score determining the overall study quality score. Results: None of the studies attained an overall high or very high score, 8% (n = 4) attained moderate, 42% (n = 21) low, and 50% (n = 25) unclear. The categories with the fewest studies assessed as ≥ high quality were SARS-CoV-2 infection (42%), sample size (30%), and assay standardization (14%). Overall quality was similar over time. No association between journal impact factor and quality score was found. Conclusions: We found that reporting in neutralization studies is widely incomplete, limiting their usefulness for downstream analyses.