Accuracy in HIV Rapid Testing among Laboratory and Non-laboratory Personnel in Zambia: Observations from the National HIV Proficiency Testing System.

BACKGROUND: Despite rapid task-shifting and scale-up of HIV testing services in high HIV prevalence countries, studies evaluating accuracy remain limited. This study aimed to assess overall accuracy level and factors associated with accuracy in HIV rapid testing in Zambia. METHODS: Accuracy was investigated among rural and urban HIV testing sites participating in two annual national HIV proficiency testing (PT) exercises conducted in 2009 (n = 282 sites) and 2010 (n = 488 sites). Testers included lay counselors, nurses, laboratory personnel and others. PT panels of five dry tube specimens (DTS) were issued to testing sites by the national reference laboratory (NRL). Site accuracy level was assessed by comparison of reported results to the expected results. Non-parametric rank tests and multiple linear regression models were used to assess variation in accuracy between PT cycles and between tester groups, and to examine factors associated with accuracy respectively. RESULTS: Overall accuracy level was 93.1% (95% CI: 91.2-94.9) in 2009 and 96.9% (95% CI: 96.1-97.8) in 2010. Differences in accuracy were seen between the tester groups in 2009 with laboratory personnel being more accurate than non-laboratory personnel, while in 2010 no differences were seen. In both PT exercises, lay counselors and nurses had more difficulties interpreting results, with more occurrences of false-negative, false-positive and indeterminate results. Having received the standard HIV rapid testing training and adherence to the national HIV testing algorithm were positively associated with accuracy. CONCLUSION: The study showed an improvement in tester group and overall accuracy from the first PT exercise to the next. Average number of incorrect test results per 1000 tests performed was reduced from 69 to 31. Further improvement is needed, however, and the national HIV proficiency testing system seems to be an important tool in this regard, which should be continued and needs to be urgently strengthened

Strong effects of home-based voluntary HIV counselling and testing on acceptance and equity: A cluster randomised trial in Zambia

Home-based voluntary HIV counselling and testing (HB-VCT) has been reported to have a high uptake, but it has not been rigorously evaluated. We designed a model for HB-VCT appropriate for wider scale-up, and investigated the acceptance of home-based counselling and testing, equity in uptake and negative life events with a cluster-randomized trial. Thirty six rural clusters in southern Zambia were pair-matched based on baseline data and randomly assigned to the intervention or the control arm. Both arms had access to standard HIV testing services. Adults in the intervention clusters were offered HB-VCT by local lay counsellors. Effects were first analysed among those participating in the baseline and post-intervention surveys and then as intention-to-treat analysis. The study was registered with www.controlled-trials.com, number ISRCTN53353725. A total of 836 and 858 adults were assigned to the intervention and control clusters, respectively. In the intervention arm, counselling was accepted by 85% and 66% were tested (n = 686). Among counselled respondents who were cohabiting with the partner, 62% were counselled together with the partner. At follow-up eight months later, the proportion of adults reporting to have been tested the year prior to follow-up was 82% in the intervention arm and 52% in the control arm (Relative Risk (RR) 1.6, 95% CI 1.4–1.8), whereas the RR was 1.7 (1.4–2.0) according to the intention-to-treat analysis. At baseline the likelihood of being tested was higher for women vs. men and for more educated people. At follow-up these differences were found only in the control communities. Measured negative life events following HIV testing were similar in both groups. In conclusion, this HB-VCT model was found to be feasible, with a very high acceptance and to have important equity effects. The high couple counselling acceptance suggests that the home-based approach has a particularly high HIV prevention potential

Strong effects of home-based voluntary HIV counselling and testing on acceptance and equity: A cluster randomised trial in Zambia

Home-based voluntary HIV counselling and testing (HB-VCT) has been reported to have a high uptake, but it has not been rigorously evaluated. We designed a model for HB-VCT appropriate for wider scale-up, and investigated the acceptance of home-based counselling and testing, equity in uptake and negative life events with a cluster-randomized trial. Thirty six rural clusters in southern Zambia were pair-matched based on baseline data and randomly assigned to the intervention or the control arm. Both arms had access to standard HIV testing services. Adults in the intervention clusters were offered HB-VCT by local lay counsellors. Effects were first analysed among those participating in the baseline and post-intervention surveys and then as intention-to-treat analysis. The study was registered with www.controlled-trials.com, number ISRCTN53353725. A total of 836 and 858 adults were assigned to the intervention and control clusters, respectively. In the intervention arm, counselling was accepted by 85% and 66% were tested (n = 686). Among counselled respondents who were cohabiting with the partner, 62% were counselled together with the partner. At follow-up eight months later, the proportion of adults reporting to have been tested the year prior to follow-up was 82% in the intervention arm and 52% in the control arm (Relative Risk (RR) 1.6, 95% CI 1.4–1.8), whereas the RR was 1.7 (1.4–2.0) according to the intention-to-treat analysis. At baseline the likelihood of being tested was higher for women vs. men and for more educated people. At follow-up these differences were found only in the control communities. Measured negative life events following HIV testing were similar in both groups. In conclusion, this HB-VCT model was found to be feasible, with a very high acceptance and to have important equity effects. The high couple counselling acceptance suggests that the home-based approach has a particularly high HIV prevention potential.publishedVersio

The seven Cs of the high acceptability of home-based VCT: Results from a mixed methods approach in Zambia

HIV testing and counselling is a critical gateway to prevention and treatment. Yet, coverage remains insufficient, few couples are tested together and gender differences in access exist. We used an embedded mixed methods approach to investigate possible explanations for the high acceptance of home-based voluntary HIV counselling and testing (HB-VCT) in a pair-matched cluster-randomized trial in Zambia. A baseline survey included 1694 individuals in 36 clusters. Adults in 18 intervention clusters were offered HB-VCT by lay counsellors. Standard testing services were available in both trial arms. After the completion of the intervention, a follow-up survey was conducted in all trial clusters. In addition, 21 in-depth interviews and one focus group discussion were conducted with home-based VCT clients in the intervention arm. Informants favoured the convenience, confidentiality and credibility of HB-VCT. Counsellors were perceived as trustworthy owing to their closeness and conduct, and the consent process was experienced as convincing. Couple testing was selected by 70% of cohabiting couples and was experienced as beneficial by both genders. Levels of first-time testing (68% vs. 29%, p < 0.0001) and re-testing (94% vs. 74%, p < 0.0001) were higher in the intervention than in the control arm. Acceptance of HIV testing and counselling is dependent on stigma, trust and gender. The confidentiality of home-based VCT was essential for overcoming stigma-related barriers, and the selection of local counsellors was important to ensure trust in the services. The high level of couple counselling within HB-VCT may contribute to closing the gender gap in HIV testing, and has benefits for both genders and potentially for prevention of HIV transmission. The study demonstrates the feasibility of achieving high test coverage with an opt-in consent approach. The embedded qualitative component confirmed the high satisfaction with HB-VCT reported in the quantitative survey and was crucial to fully understand the intervention and its consequences.publishedVersio

Task-Shifting and Quality of HIV Testing Services: Experiences from a National Reference Hospital in Zambia.

BACKGROUND: With new testing technologies, task-shifting and rapid scale-up of HIV testing services in high HIV prevalence countries, assuring quality of HIV testing is paramount. This study aimed to explore various cadres of providers' experiences in providing HIV testing services and their understanding of elements that impact on quality of service in Zambia. METHODS: Sixteen in-depth interviews and two focus group discussions were conducted with HIV testing service providers including lay counselors, nurses and laboratory personnel at purposively selected HIV testing sites at a national reference hospital in Lusaka. Qualitative content analysis was adopted for data analysis. RESULTS: Lay counselors and nurses reported confidentiality and privacy to be greatly compromised due to limited space in both in- and out-patient settings. Difficulties in upholding consent were reported in provider-initiated testing in in-patient settings. The providers identified non-adherence to testing procedures, high workload and inadequate training and supervision as key elements impacting on quality of testing. Difficulties related to testing varied by sub-groups of providers: lay counselors, in finger pricking and obtaining adequate volumes of specimen; non-laboratory providers in general, in interpreting invalid, false-negative and false-positive results. The providers had been participating in a recently established national HIV quality assurance program, i.e. proficiency testing, but rarely received site supervisory visits. CONCLUSION: Task-shifting coupled with policy shifts in service provision has seriously challenged HIV testing quality, protection of confidentiality and the process of informed consent. Ways to better protect confidentiality and informed consent need careful attention. Training, supervision and quality assurance need strengthening tailored to the needs of the different cadres of providers

Determinants of self-perceived risk of HIV infection: population-based observations in Zambia

Background Perception of risk of HIV infection has been suggested to be an important area of study as it can be an assumed to be an indicator of one’s understanding of susceptibility to HIV infection and a precursor to behavioral change, which could determine future decision making regarding risk taking. Studies that have examined perception of HIV risk and its determinants still remain limited. Zambia is among the worst affected countries by the HIV pandemic in the sub-Sahara African region. The prevalence rate is 16.5% among adults aged 15-49 years and unprotected heterosexual intercourse is the main mode of transmission. The demographic health survey in 2002 showed that HIV prevalence is higher in the urban areas (23%) as compared to the rural areas (11%); and higher among women (17.8%) as compared to men (12.6%). Combating the spread of HIV in Zambia may require a deeper understanding of key issues that are driving the pandemic. The way people receive and process information on HIV and AIDS, how they perceive themselves at risk of HIV infection and what actions they take afterwards may be a key element to the effectiveness of the programmes that can be designed or improved to reduce the spread of the disease in the different sub-groups of populations in Zambia. In this study, we set out to investigate the levels of and factors that influence self perception of risk of HIV infection among adults in populations with high HIV prevalence levels. More specifically aimed to investigate the influence of socio-demographic factors, health status indicators and sexual behaviour on self perception of HIV risk. We also intended to assess the assumed relationship between self perception of HIV risk with worry of being HIV infected, the intention to seek Voluntary Counseling and Testing (VCT) and the actual use the VCT service when offered. Methods The data was from a population based survey conducted in 2003 in selected urban and rural areas in Zambia. The survey aimed among other things to generate knowledge on HIV prevalence, distribution of patterns and trends in HIV prevalence over time and impact of HIV on mortality and fertility levels. Information on socio-demography, health status, sexual behaviour, perception 6 of risk of HIV infection and VCT was collected from both men and women. Saliva samples were collected from consenting respondents for anonymous linked HIV testing. This study on perception of risk was limited to analyses of information collected from men and women aged 15-49 years who were not aware of their own HIV status. Logistic regression was used to assess the association between level of self-perceived HIV risk and HIV prevalence in rural and urban areas. Multiple linear regression models were used to examine factors associated with self perception of HIV risk, guided by a conceptual framework, which was developed based on previous research findings in this field. Background variables included age, sex, marital status, residence and level of education. Health status indicators included were self rated health, mental distress and HIV status, and the sexual behaviour indicators were number of sexual partners and STI experiences a year before the survey. Step-wise multiple linear regression modeling was used to assess the additive effects of the groups of variables. The association of self-perceived HIV risk with worry of being HIV infected, intention and use of VCT service as per the survey, were analyzed separately using bivariate correlations functions. Results The prevalence of HIV was 13.6% in the rural area and 18.0% in the urban areas, and only 13.6% of the respondents reported to know their HIV status. Fifty percent (50%) of the respondents rated themselves to be at no risk of HIV infection, while 17% to be at high/very high risk. The likelihood of being HIV infected for rural residents was about 1.8 times higher [95% CI 1.17 – 2.63] among those who perceived themselves at high/very high risk as compared to those who perceived themselves at no risk. The association was not significant among urban residents [AOR=1.3, 95%CI 0.97 – 1.78]. The overall positive predictive value of any risk was 20%, meaning that 20% of those who perceived themselves at risk were actually HIV infected. The results of the multiple linear regression analysis showed that perception of risk did not vary by residence except for urban men after adjusting for confounders in the model. However, there were striking differences in age and sex. Perception of risk increased with age among the young people below 30 years of age and dropped with age among those aged above 30 years. The younger men appeared to perceive themselves at higher risk as compared to the young women, 7 indicating a sharp contrast when compared with the age-sex distribution of HIV prevalence which showed that women were 4 times more likely to be infected than men. Being married was associated with a high perception of risk among women as compared to the single women whereas among married men, this association was negative and significant compared to the single men upon addition of other variables in the model. Level of education and mobility were positively associated with self-perceived HIV risk among men only; on the other hand, the effect of mobility was significant among both young men and women aged15-24 years. Health status indicators measured as self rated health, HIV status and mental distress were associated with self-perceived HIV risk, with mental distress having the strongest effect and HIV status having the weakest effect. However among young people, the effect of HIV status was only significant among young women. Sexual behaviour indicators differed also by gender. Having many sexual partners was significantly associated with high self-perceived HIV risk among men though weaker and insignificant among young men aged 15-24 years. However, having experienced STI symptoms was significantly associated with self perception of risk among both men and women. Separate analyses showed that self-perceived HIV risk was strongly associated with worry about being HIV infected, intention to seek VCT and actual use of VCT were associated with self perception of HIV risk for both men and women. Conclusion About 50% of the respondents perceived themselves at risk of HIV infection, whereas the HIV prevalence in the study population was 16.1%. The association between HIV status and perception of risk was relatively low with a positive predictive value of 20% i.e. only 20% of those who perceived themselves at any risk were actually HIV infected. However, these discrepancies in perception of risk and actual risk are not surprising due to the fact that infectiousness of HIV is very low: the probability of being infected by HIV per risk exposure is < 0.001. Perceiving oneself at risk of HIV infection was strongly associated with worry of being HIV infected, mental distress and the actual use of the HIV testing services offered to them as part of the survey, indicating that HIV is a big burden in this high HIV prevalence setting and perception of risk is important in health decision making. Perception of risk was also associated with deteriorating health and past risky sexual behaviour. Strong gender differences exist in the 8 population. There is need for the empowerment of women, so that they can have negotiating skills for safe sex. Improvement of education, especially access to basic education is very important for both men and women as it provides well-informed knowledge, confers skills necessary for assimilating health promotion information on HIV & AIDS which in turn is linked to risk reduction and having accurate and correct perception of risk of HIV infection. The study on self perception of risk is a complex process where individuals are to handle conflicting information

The seven Cs of the high acceptability of home-based VCT: Results from a mixed methods approach in Zambia

HIV testing and counselling is a critical gateway to prevention and treatment. Yet, coverage remains insufficient, few couples are tested together and gender differences in access exist. We used an embedded mixed methods approach to investigate possible explanations for the high acceptance of home-based voluntary HIV counselling and testing (HB-VCT) in a pair-matched cluster-randomized trial in Zambia. A baseline survey included 1694 individuals in 36 clusters. Adults in 18 intervention clusters were offered HB-VCT by lay counsellors. Standard testing services were available in both trial arms. After the completion of the intervention, a follow-up survey was conducted in all trial clusters. In addition, 21 in-depth interviews and one focus group discussion were conducted with home-based VCT clients in the intervention arm. Informants favoured the convenience, confidentiality and credibility of HB-VCT. Counsellors were perceived as trustworthy owing to their closeness and conduct, and the consent process was experienced as convincing. Couple testing was selected by 70% of cohabiting couples and was experienced as beneficial by both genders. Levels of first-time testing (68% vs. 29%, p < 0.0001) and re-testing (94% vs. 74%, p < 0.0001) were higher in the intervention than in the control arm. Acceptance of HIV testing and counselling is dependent on stigma, trust and gender. The confidentiality of home-based VCT was essential for overcoming stigma-related barriers, and the selection of local counsellors was important to ensure trust in the services. The high level of couple counselling within HB-VCT may contribute to closing the gender gap in HIV testing, and has benefits for both genders and potentially for prevention of HIV transmission. The study demonstrates the feasibility of achieving high test coverage with an opt-in consent approach. The embedded qualitative component confirmed the high satisfaction with HB-VCT reported in the quantitative survey and was crucial to fully understand the intervention and its consequences

Expected and reported results for each DTS specimen in PT1 and PT2.

<p>Expected and reported results for each DTS specimen in PT1 and PT2.</p

Distribution of reported false and indeterminate results by tester profession in PT1 and PT2.

<p>Distribution of reported false and indeterminate results by tester profession in PT1 and PT2.</p

Proportion of tester groups who achieved a specified level of accuracy in PT1 and PT2.

<p>Proportion of tester groups who achieved a specified level of accuracy in PT1 and PT2.</p