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HIV Testing Services

HIV testing services(HTs) is an essential biomedical component of combination prevention for HIV. PSI provides HTS to help individuals learn their status and links them to appropriate follow-up services: HIV care and treatment with education and behavior promotion of risk reduction for HIV-positive individuals; and preventive services, such as voluntary medical male circumcision or treatment for sexually transmitted infections for HIV-negative individuals. HTS provides an important platform for reaching individuals with integrated health care including family planning services and tuberculosis screening.

Unit of interventionPer individual who receives HIV testing services

ComponentsPre-test counseling or education, rapid HIV-testing, post-test counseling

Target populationAdults (15-49), specific target population dependent on context

PSI implements a range of HIV prevention initiatives as part of its combination prevention approach. These include the marketing and provision of male and female condoms, HIV testing services, voluntary medical male circumcision, and linkages to care, among others. For more information about these initiatives, visit our website at:

Model Overview

PSI’s HTS model estimates the number of new HIV infections averted and the number of HIV-related DALYs averted per individual who receives HIV testing services. The model is designed with two core components: a baseline scenario in which the PSI HTS program is NOT present, and an intervention scenario, which models the hypothetical impact of a universal HTS intervention.

By comparing the intervention scenario with the baseline scenario, the model is able to estimate how many deaths and DALYs would be averted under the intervention scenario. This isolates the estimated impact of a hypothetical universal HTS intervention. The Spectrum Suite software is used to create the hypothetical scenario, in which country profiles are built in Goals and projected in the AIDS Impact Model (AIM).

To estimate the impact of a single HTS session, the model divides the death and DALY burden that would be averted under the intervention scenario by the number of HTS sessions that would be needed to achieve universal coverage. This allows us to move from a hypothetical model of universal coverage to a model which estimates the impact of a single HTS session.

Modeled Impact

In the intervention scenario, HIV Testing services is assumed to have the following impacts, depending on the outcome of the test: Referral to HTS

When a client is referred by PSI to a non-PSI service provider, such as the public sector, instead of providing the service itself, PSI claims 50% of the impact of that service. This impact is only attributed to PSI when the referral is confirmed with appropriate documentation.

Model Outputs (impact metrics)

Estimates of DALYs averted, deaths averted, CYPs provided, and unintended pregnancies averted represent the projected health impact of the intervention. It is projected because it has not been directly measured.

Examples based on HTS provided in Nigeria in 2017
Statement of modeled results, examples:

If 10,000 individuals received HTS services in Nigeria in 2017, this would avert an estimated 4 new HIV infections and 145 DALYs.