# Acceptability and usability of oral fluid HCV self-testing among health-facility users from Brazil: a cross-sectional study of 685 participants

## TL;DR

This study shows that self-testing for hepatitis C using oral fluid is acceptable and easy to use for people in Brazil's primary healthcare system.

## Contribution

The study evaluates the feasibility and acceptability of oral fluid HCV self-testing in a real-world primary care setting in Brazil.

## Key findings

- Most participants found the HCV self-test easy to use and felt safe during the process.
- The re-reading and re-testing agreements of the test were high, indicating reliable results.
- A significant proportion of participants needed assistance during the test, mainly due to sample collection errors.

## Abstract

HCV Self-Testing (HCVST) can be used to uptake HCV testing. We aimed to evaluate the acceptability/usability and re-reading/re-testing agreement of oral fluid HCVST among health-facility users in the Primary Care Systemin Brazil.

Consecutive people aged 18‒79 years using the Primary Care System (PCS) from 04-July-2022 to 30-September-2022 were invited for this cross-sectional study. The professional use OraQuick® HCV Rapid Antibody Test was used as a HCVST prototype. Oral fluid HCVST was performed relying on a step-by-step video and written/pictorial instructions. Usability was assessed by observed errors and documented need of assistance by a Healthcare Worker (HCW). After HCVST, a second HCV test was performed by the HCW using the same test-kit. Re-reading and re-testing concordances were evaluated (Cohen’s kappa, κ). Post-testing participant’s perspectives were assessed.

685 participants (74.5% female; median age = 52 [IQR 39‒61] years, 52.5% with schooling ≤ 10 years) were included. Major observed errors [%(95%CI)] were incorrect sample collection [32.8% (29.4‒36.5)] and wrong placing the test device in the tube [15.0% (12.6‒17.9)]. A total of 35.6% (95% CI 32.1‒39.3) of participants needed assistance in at least one step of HCVST. Re-reading and re-testing agreements were 95.2% (κ = 0.56) and 99.7% (κ = 0.67; n = 626 excluding invalid tests), respectively. After HCVST, 93% felt safe, 99% would be willing to test again, and 99% would recommend HCVST. Most participants rated the HCVST experience as easy (73%) or very easy (24%).

Oral-fluid HCVST was feasible and well-accepted among users of the PCS in Brazil. HCVST can be an alternative to scale-up HCV testing.