CC BY 4.0 · European Dental Research and Biomaterials Journal 2022; 03(01/02): 021-025
DOI: 10.1055/s-0043-1768174
Original Article

The Effect of Correlation of Laboratory-Developed Test and Initial Symptoms and False Negatives in RT-PCR Strategies for COVID-19 Patients with Beta Variants

1   OMFS Department of Augusta University, Georgia, United States
2   Master of Craniofacial Reconstruction and Trauma Queen Marry, University of London, London, Great Britain
3   Virology Research Center, National Research Institute of Tuberculosis and Lung Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
4   Georgia School of Orthodontics, Atlanta, Georgia, United States
3   Virology Research Center, National Research Institute of Tuberculosis and Lung Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
5   Department of Otolaryngology, Masih Daneshvari Hospital, Tehran, Iran
6   Department of Radiology, Ziyaian Hospital, Tehran University of Medical Sciences, Tehran, Iran
7   Cancer Institute of Imam Khomeini, Faculty of Medicine, Tehran University of Medical Science, Tehran, Iran
8   Psychology Department, University of South Alabama, Mobile, Alabama, United States
9   Masih Daneshvari Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
10   School of Dentistry, University of Pennsylvania, Philadelphia, Pennsylvania, United States
› Author Affiliations
Funding No funding was taken for this research.


Objective Reverse transcription-polymerase chain reaction (RT-PCR) assays detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The number of viruses in the sample varies between patients; it depends on sample location, nasal or throat, and with time infection spreads. Previous studies showed that the viral load of coronavirus disease 2019 (COVID-19) infection is the peak just before symptoms onset. Furthermore, positive and negative results depend on test site, sampling, and timing method; RT-PCR can be 1 to 30% false-negative result.

Materials and Methods Within this study, we took RT-PCR test from COVID-19 positive patients who already had the confirmation of the disease either by lung computed tomography (CT)-scan or the symptoms such as dyspnea. The study was explained to all the patients, and they confirmed to take the RT-PCR test. Negative samples from those patients were retested, and if the result came back negative, we included them as negative in the result.

Result A total number of 49 patients (25 females) and (24 males) with a mean age of 53.24 years (ranging from 32 to 77) were enrolled. About 32.3% of patients, despite having COVID-19 disease, had a negative RT-PCR test. There is a positive and significant relationship between weight (r = 0.253) and CT at the time of hospitalization of COVID-19 patients and a negative and significant relationship with O2 saturation without oxygen therapy (r =  − 0.296), the model can predict 67.7% of the disease due to the beta value, and the share of O2 saturation without oxygen therapy is more than weight.

Conclusion We show that a pragmatic model can be designed to predict which patients have a higher chance of getting false-negative result, and should be retested for COVID-19. Among the variables, weight had a negative and significant relationship, and O2 saturation without respiratory support had a negative and significant relationship with COVID-19 disease.

Authors' Contribution

S.G.H. helped in conceptualization, methodology, supervision, project administration, and writing—review & editing. S.A.N. was involved in conceptualization, data curation, methodology, and supervision. M.D. contributed to conceptualization, formal analysis, methodology, project administration, and writing—review & editing. M.K.G. and N.R. helped in data curation, formal analysis, methodology, and investigation. M.N. and G.h.M. were involved in investigation, validation, and writing—original draft. N.K. and E.A. helped in investigation and writing—original draft. A.E. contributed to investigation, validation, and data curation.

Availability of Data and Materials

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Publication History

Article published online:
21 April 2023

© 2023. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (

Thieme Medical and Scientific Publishers Pvt. Ltd.
A-12, 2nd Floor, Sector 2, Noida-201301 UP, India

  • References

  • 1 Sarwar H, Akhtar H, Naeem MM. et al. COVID-19 pandemic and challenges of dentistry: self-reported effectiveness of e-learning classes during COVID-19 pandemic: a nation-wide survey of Pakistani undergraduate dentistry students. Eur J Dent 2020; 14 (S 01) S34-S43
  • 2 Hamid H, Khurshid Z, Adanir N, Zafar MS, Zohaib S. COVID-19 pandemic and role of human saliva as a testing biofluid in point-of-care technology. Eur J Dent 2020; 14 (S 01): S123-S129
  • 3 Guan WJ, Ni ZY, Hu Y. et al; China Medical Treatment Expert Group for Covid-19. Clinical characteristics of coronavirus disease 2019 in China. N Engl J Med 2020; 382 (18) 1708-1720
  • 4 Wang D, Hu B, Hu C. et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China. JAMA 2020; 323 (11) 1061-1069
  • 5 Hanson KE, Caliendo AM, Arias CA. et al. Infectious Diseases Society of America Guidelines on the Diagnosis of COVID-19:Serologic Testing. Clin Infect Dis 2020; ciaa1343
  • 6 Clinical, Laboratory, and Radiologic Characteristics of Patients With Initial False-Negative Severe Acute Respiratory Syndrome Coronavirus 2 Nucleic Acid Amplification Test Results | Open Forum Infectious Diseases | Oxford Academic. Accessed January 16, 2023 at:
  • 7 Wikramaratna PS, Paton RS, Ghafari M, Lourenço J. Estimating the false-negative test probability of SARS-CoV-2 by RT-PCR. Euro Surveill 2020; 25 (50) 2000568
  • 8 Khurshid Z, Asiri FYI, Al Wadaani H. Human saliva: non-invasive fluid for detecting novel coronavirus (2019-nCoV). Int J Environ Res Public Health 2020; 17 (07) 2225
  • 9 Warsi I, Khurshid Z, Shazam H. et al. Saliva exhibits high sensitivity and specificity for the detection of SARS-COV-2. Diseases 2021; 9 (02) 38
  • 10 Abdolrahimzadeh Fard H, Mahmudi-Azer S, Sefidbakht S. et al. Evaluation of Chest CT scan as a screening and diagnostic tool in trauma patients with coronavirus disease 2019 (COVID-19): a cross-sectional study. Emerg Med Int 2021; 2021: 4188178
  • 11 Abdolrahimzadeh Fard H, Borazjani R, Sabetian G. et al. Establishment of a novel triage system for SARS-CoV-2 among trauma victims in trauma centers with limited facilities. Trauma Surg Acute Care Open 2021; 6 (01) e000726
  • 12 Bwire GM, Majigo MV, Njiro BJ, Mawazo A. Detection profile of SARS-CoV-2 using RT-PCR in different types of clinical specimens: a systematic review and meta-analysis. J Med Virol 2021; 93 (02) 719-725
  • 13 Arevalo-Rodriguez I, Buitrago-Garcia D, Simancas-Racines D. et al. False-negative results of initial RT-PCR assays for COVID-19: a systematic review. PLoS One 2020; 15 (12) e0242958
  • 14 Mallett S, Allen AJ, Graziadio S. et al. At what times during infection is SARS-CoV-2 detectable and no longer detectable using RT-PCR-based tests? A systematic review of individual participant data. BMC Med 2020; 18 (01) 346
  • 15 Rahbari R, Moradi N, Abdi M. rRT-PCR for SARS-CoV-2: analytical considerations. Clin Chim Acta 2021; 516: 1-7
  • 16 Zhou Y, Pei F, Ji M. et al. Sensitivity evaluation of 2019 novel coronavirus (SARS-CoV-2) RT-PCR detection kits and strategy to reduce false negative. PLoS One 2020; 15 (11) e0241469
  • 17 Xiao Y, Shi X, She Q. et al. Exploration of turn-positive RT-PCR results and factors related to treatment outcome in COVID-19: a retrospective cohort study. Virulence 2020; 11 (01) 1250-1256
  • 18 Mistry DA, Wang JY, Moeser ME, Starkey T, Lee LYW. A systematic review of the sensitivity and specificity of lateral flow devices in the detection of SARS-CoV-2. BMC Infect Dis 2021; 21 (01) 828
  • 19 Subali AD, Wiyono L. Reverse transcriptase loop mediated isothermal amplification (RT-LAMP) for COVID-19 diagnosis: a systematic review and meta-analysis. Pathog Glob Health 2021; 115 (05) 281-291
  • 20 Suo T, Liu X, Feng J. et al. ddPCR: a more accurate tool for SARS-CoV-2 detection in low viral load specimens. Emerg Microbes Infect 2020; 9 (01) 1259-1268
  • 21 Chaimayo C, Kaewnaphan B, Tanlieng N. et al. Rapid SARS-CoV-2 antigen detection assay in comparison with real-time RT-PCR assay for laboratory diagnosis of COVID-19 in Thailand. Virol J 2020; 17 (01) 177
  • 22 Xie X, Zhong Z, Zhao W, Zheng C, Wang F, Liu J. Chest CT for typical coronavirus disease 2019 (COVID-19) pneumonia: relationship to negative RT-PCR testing. Radiology 2020; 296 (02) E41-E45