This is a controlled study intended to evaluate the usability, label comprehension and performance of the INSTI® HCV Self Test in the hands of untrained lay users using fingerstick blood, with instructions for use specifically designed for a lay person who has not used any hepatitis C rapid self test prior to the study and to assess "lay" users ability to comprehend key concepts and information provided on the outside of the pouch and in the accompanying Instructions for Use. Comprehension will be assessed without product familiarization (demonstration/training) by a healthcare professional.

The HSTAR012 is a controlled study intended to evaluate the usability, label comprehension and performance of the INSTI® HCV Self Test in the hands of untrained lay users using fingerstick blood, with instructions for use specifically designed for a lay person who has not used any hepatitis C rapid self test prior to the study and to assess "lay" users ability to comprehend key concepts and information provided on the outside of the pouch and in the accompanying Instructions for Use. Comprehension will be assessed without product familiarization (demonstration/training) by a healthcare professional.

Specific critical and non-critical steps are identified from the self-test product's Instructions for Use. The untrained lay user is evaluated for process success or difficulty by a silent, non-interacting observer in the same room. Overall processes include self-test Usability (observation to determine if a participant performs all critical steps correctly), Interpretation of results (confirmation by staff to determine if participant interprets their test correctly), and labelling Comprehension (questionnaire to determine that the participant is aware of test limitations and what to do following the test result). The successful completion of steps will be evaluated as a percentage of the overall process, with all critical and non-critical errors identified and reported. All self-test results will be confirmed by testing with the same test by collecting additional fingerstick samples by a trained HCP (aka. Trained Observer). The level of agreement between the results of the investigated test (i.e., INSTI® HCV Self Test) obtained by a lay user and those obtained by a healthcare worker will be calculated.

Additionally, EDTA venous blood samples will be collected from each participant and sent to a laboratory to perform an enzyme immunoassay (EIA) using a state-of-the-art quality-assured assay (prequalified by WHO, CE-IVD or FDA approved). The sensitivity and specificity of the INSTI® HCV Self Test will be also calculated and the results from both tests conducted by the lay user and trained HCP compared to the results of the laboratory assay.

In the event of discrepant results between INSTI® HCV Self Test and the laboratory-based EIA assay, EDTA venous whole blood will be collected to perform HCV RNA assay to confirm active infection, study participants with positive results in HCV RNA test will be contacted and linked to care following local algorithms.

Study Aim

1. To evaluate the ability of untrained lay users to obtain an accurate test result using the INSTI® HCV Self Test.
2. To evaluate the untrained lay users' interaction with the device in terms of effectiveness and efficiency, i.e., successful/unsuccessful completion and difficulty of the critical steps as per the Instructions for Use.
3. To evaluate the performance (diagnostic sensitivity and specificity) of INSTI® HCV self-test by the lay user in comparison with laboratory confirmatory test.
4. To evaluate the performance (diagnostic sensitivity and specificity) of INSTI® HCV self-test by the healthcare professional in comparison with laboratory confirmatory test.
5. To evaluate the concordance of the results between the trained observer and the untrained lay user
6. To assess the ability of untrained lay users to correctly comprehend key messaging from device packaging and labelling, including the Instructions for Use.
7. To understand the experience and satisfaction of study participants with the overall self-testing process.
8. To assess whether or not the participants locate and read the information included in the IFU, know what the products are used for, and when it's appropriate/inappropriate to use the product.

Inclusion Criteria:

• ≥18 years of age
• Understand and sign the written informed Consent Form in English
• Have unknown HCV serology status, i.e., never tested for HCV or tested negative but the last testing was done at least 6 months before the enrolment date.
• Able to complete the required testing on the allocated testing day[s]
• Agree to provide accurate medical history, required specimens of finger prick blood samples for self-test devices, and up to 3.5ml of blood by venipuncture for laboratory testing.
• Able to speak and read English.

Exclusion Criteria:

• Do not meet all of the inclusion criteria.
• Are known HCV positive.
• Have received any experimental HCV vaccine.
• Have participated in any prior, or concurrent studies of self-testing including any blood based RDTs.
• A practicing medical healthcare professional (doctor, nurse or Counsellor that performs testing with RDTs)
• Any condition which, in the opinion of the facilitator, would make the participant unsuitable or unsafe for enrolment or could interfere with the completion of the assessment, consent form and questionnaire etc. or bias the outcome, i.e., being unable to see / read by forgetting to bring reading glasses, being intoxicated or acute sickness.