NCT04745533

Brief Summary

Stopping the SARS-CoV2 spread is essential to control the pandemic cause by this virus. A great effort is being made to carry out surveillance, case detection and contact control protocols in order to detect and isolate those contagious subjects. Since both symptomatic and asymptomatic subjects can be contagious, a surveillance system based on the presence of symptoms is not enough, requiring to perform diagnostic tests in a large number of subjects, such as asymptomatic contacts or high-prevalence populations, and repeatedly. Moreover, the speed in obtaining results is crucial in order not to delay the isolations of positive subjects. The polymerase chain reaction (PCR) is an expensive test which requires specialized equipment and personnel with a delay in results of 24-48 hours. In addition, its high sensitivity can mean that subjects without infective capacity have a positive result. In contrast, antigen detection tests (ADTs) are cheap and easy to perform, having a result in few minutes. They have shown high sensitivity and specificity in symptomatic subjects, specially in the first week of symptoms when the viral load is high. This could be very useful for the study of asymptomatic contacts to detect those with potential contagiousness quick, easily and cheaply. However, there is no evidence to support the use of ADTs in this group of subjects. For this reason, the investigators propose to carry out a study to compare the diagnostic efficacy of ADTs versus PCR in the group of subjects considered to be close contacts of SARS-Cov2 positive patients in the health area of Cáceres.

Trial Health

15
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Timeline
Completed

Started Feb 2021

Shorter than P25 for all trials

Status
withdrawn

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

February 4, 2021

Completed
5 days until next milestone

First Posted

Study publicly available on registry

February 9, 2021

Completed
6 days until next milestone

Study Start

First participant enrolled

February 15, 2021

Completed
2 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 30, 2021

Completed
2 months until next milestone

Study Completion

Last participant's last visit for all outcomes

June 30, 2021

Completed
Last Updated

April 29, 2026

Status Verified

April 1, 2026

Enrollment Period

2 months

First QC Date

February 4, 2021

Last Update Submit

April 28, 2026

Conditions

Keywords

Antigen detection testsDiagnostic efficacyContact studyAsymptomatic contacts

Outcome Measures

Primary Outcomes (2)

  • Sensitivity of the antigen detection test used in the study of contacts of COVID-19 patients.

    The investigators will analyze the probability of a positive antigen detection test result in a COVID-19 patient contact with a positive polymerase chain reaction test.

    2 days

  • Specificity of the antigen detection test used in the study of contacts of COVID-19 patients.

    The investigators will analyze the probability of a negative antigen detection test result in a COVID-19 patient contact with a negative polymerase chain reaction test.

    2 days

Secondary Outcomes (10)

  • Positive predictive value of the antigen detection test used in the study of contacts of COVID-19 patients.

    2 days

  • Negative predictive value of the antigen detection test used in the study of contacts of COVID-19 patients.

    2 days

  • Positive likelihood ratio of the antigen detection test used in the study of contacts of COVID-19 patients.

    2 days

  • Negative likelihood ratio of the antigen detection test used in the study of contacts of COVID-19 patients.

    2 days

  • Change in the pretest probability when the antigen detection test result is positive in a COVID-19 patient contact.

    2 days

  • +5 more secondary outcomes

Study Arms (1)

SARS-CoV2 contacts

Subjects considered close contacts of COVID-19 patients according to the definition of the Ministry of Health in the health area of Cáceres.

Diagnostic Test: Antigen detection test

Interventions

Antigen detection testDIAGNOSTIC_TEST

To compare the results of the antigen detection test against the polymerase chain reaction in the study of contacts of COVID-19 patients during quarantine.

SARS-CoV2 contacts

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

All subjects considered close contacts of COVID-19 patients according to the definition of the Ministry of Health of Spain in the health area of Cáceres

You may not qualify if:

  • Subjects who do not obtain their informed consent for the study.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

MeSH Terms

Conditions

Severe Acute Respiratory Syndrome

Condition Hierarchy (Ancestors)

Respiratory Tract InfectionsInfectionsCoronavirus InfectionsCoronaviridae InfectionsNidovirales InfectionsRNA Virus InfectionsVirus DiseasesRespiratory Tract Diseases
0

Study Design

Study Type
observational
Observational Model
COHORT
Time Perspective
PROSPECTIVE
Sponsor Type
OTHER
Responsible Party
SPONSOR INVESTIGATOR
PI Title
Principal investigator

Study Record Dates

First Submitted

February 4, 2021

First Posted

February 9, 2021

Study Start

February 15, 2021

Primary Completion

April 30, 2021

Study Completion

June 30, 2021

Last Updated

April 29, 2026

Record last verified: 2026-04

Data Sharing

IPD Sharing
Will share

Additional related documents such as study protocol, statistical analysis plan and informed consent form will be available upon request from the project principal investigator. (Dr. Juan Fernando Masa Jiménez). De-identified patients´data can be requested by researchers for use in independent scientific research and will provided following review and approval of the research proposal (including statistical analysis plan) and completion of a data sharing agreement with the Project Publications Committee. Investigator Data requests can be made anytime from 1 to 2 years after the publication of this trial. Requests should be sent to the corresponding author (Dr. Juan Fernando Masa Jiménez- fmasa@separ.es)