Research Article

Comparing the effectiveness of different vaccination regimens using Sinovac and BNT162b2 vaccines among hospitalised patients: A single-centre hospital-based retrospective cohort study

Volume: 11 Number: 6 November 4, 2025
EN

Comparing the effectiveness of different vaccination regimens using Sinovac and BNT162b2 vaccines among hospitalised patients: A single-centre hospital-based retrospective cohort study

Abstract

Objectives: This study aimed to assess the effectiveness of different vaccination regimens using two distinct SARS-CoV-2 vaccines against mortality risk and the need for intensive care unit (ICU) admission among hospitalised patients.

Methods: The single-centre hospital-based retrospective cohort study was performed with adult COVID-19 patients in a tertiary-level hospital between March 2020 and September 2022. The associations between patients’ demographics and clinical features, vaccine status and regimens, in-hospital mortality, and need for ICU admission were evaluated using multivariable regression analyses.

Results: During the study period, 2,373 patients were included. Mortality among unvaccinated patients was 85.0%, which was significantly lower in vaccinated groups (P<0.001), particularly with BNT162b2 than with Sinovac. Vaccination reduced mortality and ICU admission rates, with higher efficacy observed with increased vaccine doses and BNT162b2 regimens. Multivariable analyses confirmed age as a significant determinant and various vaccination schedules showed consistent reductions in mortality and ICU admissions.

Conclusions: A two-dose initial plus one or more-dose booster BNT162b2 regimen effectively reduced mortality risks and ICU admission.

Keywords

Ethical Statement

This study was approved by the University of Health Sciences, Bursa Yüksek Ihtisas Training and Research Hospital, Clinical Research Ethics Committee (Decision no. 2011-KAEK-25 2022/04-18, date: 20.04.2022).

References

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Details

Primary Language

English

Subjects

Medical Virology, Primary Health Care

Journal Section

Research Article

Early Pub Date

June 1, 2025

Publication Date

November 4, 2025

Submission Date

February 3, 2025

Acceptance Date

March 9, 2025

Published in Issue

Year 2025 Volume: 11 Number: 6

APA
Turan, A., Öğüt, H., Ayyıldız Varol, A., Koca, N., & Bozkurt, H. (2025). Comparing the effectiveness of different vaccination regimens using Sinovac and BNT162b2 vaccines among hospitalised patients: A single-centre hospital-based retrospective cohort study. The European Research Journal, 11(6), 1167-1175. https://doi.org/10.18621/eurj.1632009
AMA
1.Turan A, Öğüt H, Ayyıldız Varol A, Koca N, Bozkurt H. Comparing the effectiveness of different vaccination regimens using Sinovac and BNT162b2 vaccines among hospitalised patients: A single-centre hospital-based retrospective cohort study. Eur Res J. 2025;11(6):1167-1175. doi:10.18621/eurj.1632009
Chicago
Turan, Atakan, Hamdi Öğüt, Aylin Ayyıldız Varol, Nizameddin Koca, and Hayri Bozkurt. 2025. “Comparing the Effectiveness of Different Vaccination Regimens Using Sinovac and BNT162b2 Vaccines Among Hospitalised Patients: A Single-Centre Hospital-Based Retrospective Cohort Study”. The European Research Journal 11 (6): 1167-75. https://doi.org/10.18621/eurj.1632009.
EndNote
Turan A, Öğüt H, Ayyıldız Varol A, Koca N, Bozkurt H (November 1, 2025) Comparing the effectiveness of different vaccination regimens using Sinovac and BNT162b2 vaccines among hospitalised patients: A single-centre hospital-based retrospective cohort study. The European Research Journal 11 6 1167–1175.
IEEE
[1]A. Turan, H. Öğüt, A. Ayyıldız Varol, N. Koca, and H. Bozkurt, “Comparing the effectiveness of different vaccination regimens using Sinovac and BNT162b2 vaccines among hospitalised patients: A single-centre hospital-based retrospective cohort study”, Eur Res J, vol. 11, no. 6, pp. 1167–1175, Nov. 2025, doi: 10.18621/eurj.1632009.
ISNAD
Turan, Atakan - Öğüt, Hamdi - Ayyıldız Varol, Aylin - Koca, Nizameddin - Bozkurt, Hayri. “Comparing the Effectiveness of Different Vaccination Regimens Using Sinovac and BNT162b2 Vaccines Among Hospitalised Patients: A Single-Centre Hospital-Based Retrospective Cohort Study”. The European Research Journal 11/6 (November 1, 2025): 1167-1175. https://doi.org/10.18621/eurj.1632009.
JAMA
1.Turan A, Öğüt H, Ayyıldız Varol A, Koca N, Bozkurt H. Comparing the effectiveness of different vaccination regimens using Sinovac and BNT162b2 vaccines among hospitalised patients: A single-centre hospital-based retrospective cohort study. Eur Res J. 2025;11:1167–1175.
MLA
Turan, Atakan, et al. “Comparing the Effectiveness of Different Vaccination Regimens Using Sinovac and BNT162b2 Vaccines Among Hospitalised Patients: A Single-Centre Hospital-Based Retrospective Cohort Study”. The European Research Journal, vol. 11, no. 6, Nov. 2025, pp. 1167-75, doi:10.18621/eurj.1632009.
Vancouver
1.Atakan Turan, Hamdi Öğüt, Aylin Ayyıldız Varol, Nizameddin Koca, Hayri Bozkurt. Comparing the effectiveness of different vaccination regimens using Sinovac and BNT162b2 vaccines among hospitalised patients: A single-centre hospital-based retrospective cohort study. Eur Res J. 2025 Nov. 1;11(6):1167-75. doi:10.18621/eurj.1632009