The iLink Study examines whether a Conditional Economic Incentive (CEI) may be an effective tool for improving linkage to HIV treatment and care following referral for antiretroviral therapy (ART) services from a mobile health clinic in Cape Town, South Africa. The study examines the feasibility and acceptability of using a R300 (approximately $25 as of April 2015) voucher - that is exchanged for cash upon initiation of ART within 3 months - to increase the uptake of ART among men and women living in low-income areas. This pilot study (n=64) includes a randomised control trial, follow-up telephone calls and medical record reviews, and in-depth interviews.

The initiation of combination antiretroviral therapy (ART) remains a serious challenge globally, and particularly in South Africa, the country with the largest population of people living with HIV worldwide (UNAIDS 2012). South Africa has the largest ART programme globally, yet only half of those needing ART in South Africa were receiving treatment in 2011 (Johnson 2012). Early initiation of ART improves treatment outcomes and reduces AIDS-related morbidity and mortality. Recent studies have demonstrated a secondary benefit of ART in preventing HIV transmission by reducing viral load and thus transmissibility (Cohen et al. 2011; Montaner et al. 2010; Tanser et al. 2013). Despite the personal and public health benefits of ART, South African studies have shown large loss to follow-up at each of the stages required for ART initiation: (1) initial CD4 count testing and returning for results; (2) attending ART readiness counselling; and (3) returning to initiate ART (April et al. 2009; Bassett et al. 2010; Kranzer et al. 2010; Larson et al. 2010; Losina et al. 2010).

Novel interventions are urgently needed to improve linkage to HIV treatment and care post-diagnosis, as increased ART coverage will reduce AIDS-related morbidity and mortality, and HIV incidence. Improving ART coverage is therefore a priority in many regions of the world, and particularly in sub-Saharan Africa, where AIDS remains a key development challenge. Interventions based on theories from the field of behavioural economics, a hybrid of principles from psychology and economics (Bickel et al. 1995), have great potential to help strengthen the contributions of psychology to improving ART outcomes. Conditional economic incentives (CEIs), a financial incentive given upon completion of an outcome that can be objectively measured (i.e. ART initiation), has the potential to leverage two theoretical principles from behavioural economics to improve ART initiation. First, instead of being completely rational and accurate, decision-making is viewed as inherently biased due to a multitude of social-cognitive and affective factors that play a role in cost-benefit analysis, such as emotions, personal beliefs, and contextual factors (Fiske & Taylor 2008). In other words, people's preferred outcomes are largely determined by salient contextual needs (Operario et al. 2013). Second, people have a tendency to give greater value to rewards in the present or near future than those in the more distant future (a phenomenon economists term temporal discounting) and therefore decision-making favours immediate rewards and heavily discounts future outcomes. This poses a challenge for ART initiation as the future benefits of ART may be valued less than an individual's more immediate needs, especially for individuals who currently perceive themselves to be relatively healthy.

A CEI may help overcome this challenge for ART initiation by increasing its immediate benefits. A CEI may therefore help 'nudge' individuals to initiate ART by altering the cost-benefit ratio so that the benefits of ART (i.e. the immediate financial reward and the future health reward) outweigh the immediate costs of ART initiation, such as transport, time off work, long waiting lines and the fear of stigma. The application of CEIs to address HIV prevention and treatment problems is still in its infancy, but they have been successfully employed to improve adherence to ART (Rosen et al. 2007; Sorensen et al. 2007; Javanbakht et al. 2010), increase HIV testing uptake and the collection of HIV tests results (Thornton 2008), and reduce risky sexual behaviours (Baird et al. 2012). This evidence indicates that small incentives-based interventions can 'nudge' individuals towards adopting healthier behaviours.

The proposed research will make a significant contribution to our knowledge about demand creation for HIV treatment and prevention services by examining whether CEIs may also be an effective tool for improving linkage to HIV treatment and care following referral for ART services. The proposed research will examine the feasibility and acceptability of using CEIs to increase the uptake of ART among men and women who are referred for ART services. Our long-term collaborative goal is to utilize the results from this pilot study to prepare a grant application for a fully-powered RCT examining whether CEIs can increase ART initiation.

Objectives To examine the acceptability and feasibility of an incentive intervention aimed at increasing uptake of ART among men and women who are referred for ART (CD4 < 500 or WHO stage 4) by a mobile health clinic.

Acceptability

• Did participants find the randomization process fair and acceptable?
• Was the intervention an incentive that motivated or encouraged uptake of ART?
• Was the incentive amount and type acceptable?
• Were individuals in the control arm discouraged from ART initiation because they felt that their linkage to care efforts were not rewarded?
• Were there cases of patients who were unsatisfied or disappointed as a consequence of the study (eg. they did not receive the incentive, yet they thought they should)?

Feasibility

• Is it possible to recruit men and women into the study on the day of being referred for ART?

• Is it possible to track individuals and recruit individuals for in-depth interviews?

• Is it possible to implement the study as planned:

  • Did the randomization process work?
  • Did participants understand the incentive system?
  • Did participants believe that they would actually receive the incentive?
  • Did the incentive delivery method work?

• What is the potential for individuals to game the incentive system? Did any individuals find a method of receiving the money without starting ART?

Potential Efficacy

• Is ART initiation more likely among men and women who are offered the incentive compared to men and women who are not offered the incentive?
• Is early ART initiation more likely among men and women who are offered the incentive compared to men and women who are not offered the incentive?
• Does retention in care after ART initiation differ among men and women who are offered the incentive compared to men and women not offered the incentive?
• What is the potential for incentives to improve ART initiation given participants behavioural intentions regarding ART initiation and barriers to ART initiation?

Inclusion Criteria:

• Referred for ART by the Tutu Tester Mobile Clinic (CD4 ≤ 500 or WHO stage 4)
• Planning to live in the study area for the next 6 months
• Willing and able to provide written informed consent for study participation
• Willing to accept calls from the study staff

Exclusion Criteria:

• Participated in the study previously
• Previously been on ART
• Intoxicated at the time of enrolment