Fig 1.
Instructions for use of the Triplex HIV/HCV/HBsAg self-test designed for the Congolese general public using typical pictures representative of the principal steps of the manufacturer’s instructions with explanations written in Lingala, which is one of the most frequently used vernacular languages of the former Province Orientale of the Democratic Republic of the Congo.
Other available languages were French and Swahili. A. Identification of the components: Ⓐ Pouch, Ⓑ Test cassette, Ⓒ Diluent vial, Ⓓ Alcohol wipe, Ⓔ Compress, Ⓕ Lancet, Ⓖ Pipette, Ⓗ Dressing. B. Performing the Triplex self-test: 1. Check the contents of the kit consisting of seven components; 2. Take the self-test Ⓑ out of the bag Ⓐ and open the diluent vial Ⓒ; 3. Disinfect the chosen fingertip with the alcohol wipe Ⓓ; 4. Wipe off residual alcohol with the compress Ⓔ; 5. Remove the cap of the lancet Ⓕ; 6. Apply the lancet Ⓕ on the chosen fingertip and push the other tip to sting; 7. Press gently on the fingertip to obtain a large drop of blood; 8. Place the lower part of the pipette Ⓖ horizontally over the blood drop to aspirate the blood until the mark (black) is reached. Note: Press the fingertip again if necessary, to obtain the required amount of blood. Check that the lower part of the pipette is filled with blood up to the mark. Immediately place the drop of BLOOD into the SQUARE well of the cassette Ⓑ. 9. Shed four drops of diluent in the ROUND well DILUENT of the test cassette Ⓑ; 10. Wait exactly 15 minutes before reading the result; 11. Apply the dressing Ⓗ.
Fig 2.
Flow chart showing the development of the Triplex HIV/HCV/HBsAg self-test, the recruitment of study participants, and their participation for each substudy.
DBS: Dried blood spot.
Table 1.
The demographic characteristics and medical history of the 251 study participants.
Table 2.
Analytical results of the observation concerning the ability of the 251 study participants to correctly use each step of the Triplex HIV/HCV/HBsAg self-test autonomously or with verbal help using the printed instruction for use versus the combination of printed and video instructions for use (substudy 1).
Table 3.
Multivariate regression analysis of factors associated with the correct use without difficulties, errors, and helps (substudy 1), the need for verbal help when performing the self-test (substudy 1), and the correct interpretation of the Triplex HIV/HCV/HBsAg self-test results (substudy 2) among the 251 study participants.
Table 4.
Items and analytical results of the satisfaction questionnaire concerning the overall performance of the Triplex HIV/HCV/HBsAg self-test (substudy 1) and interpretation of the Triplex self-test results (substudy 2).
Fig 3.
Stacked columns showing analytical results of the interpretation of the Triplex HIV/HCV/HBsAg self-test results among the 251 study participants.
A. Overall interpretation of Triplex self-test results in the whole study population, including those using exclusively the paper-based instructions for use (PIFU) and those using both printed and video instructions for use (P&VIFU); B. Distribution of misinterpreted Triplex self-test results, including 50 positive tests misinterpreted as negative (dark grey; n = 30) or as positive but with confusion in band interpretation (lying grey hatches; n = 20), 23 negative tests misinterpreted as invalid (vertical grey hatches; n = 18), or positive (horizontal grey hatches; n = 5), and 1 invalid tests misinterpreted as negative (dark grey); C. Percentages of correctly interpreted and misinterpreted HIV band read as positive and negative; D. Percentages of correctly interpreted and misinterpreted HCV band read as positive and negative; E. Percentages of correctly interpreted and misinterpreted HBsAg band read as positive and negative. Columns in black represent misinterpretation, whereas columns in white represent correct interpretation. NS: Not significant; PIFU: Paper-based instructions for use; P&VIFU: Paper-based and video instructions for use.
Table 5.
Correspondence between the interpretation of the Triplex HIV/HCV/HBsAg self-test results by the participants and by the trained observers among 20 results of the Triplex self-test correctly identified as positive but misinterpreted because of discordance of positive bands.
Table 6.
Analytical results of the acceptability of and the preferences for the Triplex HIV/HCV/HBsAg self-test among 251 study participants.