BACKGROUND: Improving the means to detect SARS-COV-2 infection is important in the ongoing battle against the COVID-19 pandemic. STANDARDTM Q COVID-19 Ag Test offers an easy to use, cheap and rapid way of testing that must be evaluated first to optimize its utility.

OBJECTIVES: This study aims to evaluate the diagnostic accuracy of this test kit compared with Reverse Transcription Polymerase Chain Reaction (RT-PCR) for SARS-COV-2 diagnosis.

METHODS: Using retrospective cross-sectional study, seventy seven (77) nasopharyngeal swabs in viral transport media were used to determine the sensitivity, specificity, positive predictive value and negative predictive value of STANDARDTM Q COVID-19 Ag Test compared with the reference method, RT-PCR.

RESULTS: Among all participants, the rapid antigen test has a sensitivity of 9.86%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 8.57%. The sensitivity increases among symptomatic participants and when Ct value is less than 20 to 25.00% and 31.58%, respectively.

CONCLUSION: Despite the low sensitivity, STANDARDTM Q COVID-19 Ag Test has a high specificity and positive predictive value and could be a cheap and efficient test in the proper clinical context. Its use in conjunction with RT-PCR for those who tested negative initially should be emphasized in the implementation of the existing policies.