Data from: Improving rational use of ACTs through diagnosis-dependent subsidies: evidence from a cluster-randomized controlled trial in western Kenya

Background: More than half of artemisinin combination therapies (ACTs)
consumed globally are dispensed in the retail sector where diagnostic
testing is uncommon, leading to overconsumption and poor targeting. In
many malaria-endemic countries, ACTs sold over-the-counter are available
at heavily subsidized prices, further contributing to their misuse.
Inappropriate use of ACTs can have serious implications for the spread of
drug resistance and leads to poor outcomes for non-malaria patients
treated with incorrect drugs. We evaluated the public health impact of an
innovative strategy that targets ACT subsidies to confirmed malaria cases
by coupling free diagnostic testing with a diagnosis-dependent ACT
subsidy. Methods and Findings: We conducted a cluster-randomized
controlled trial in 32 community clusters in western Kenya (population
~160,000). Eligible clusters had retail outlets selling ACTs and existing
community health worker (CHW) programs and were randomly assigned 1:1 to
control and intervention arms. In intervention areas, CHWs were available
in their villages to perform malaria rapid diagnostic tests on demand for
any individual >1 year of age experiencing a malaria-like illness.
Malaria RDT positive individuals received a voucher for a discount on a
quality-assured ACT, redeemable at a participating retail medicine outlet.
In control areas, CHWs offered a standard package of health education,
prevention and referral services. We conducted four population-based
surveys, at baseline, 6 months, 12 months and 18 months, of a random
sample of households with fever in the last 4 weeks to evaluate
predefined, individual-level outcomes. The primary outcome was uptake of
malaria diagnostic testing at 12 months. The main secondary outcome was
rational ACT use, defined as the proportion of ACTs used by test-positive
individuals. Analyses followed the intention-to-treat principle using
generalized estimating equations to account for clustering with
pre-specified adjustment for gender, age, education and wealth. All
descriptive statistics and regressions were weighted to account for
sampling design. Between July 2015 and May 2017, 32,404 participants were
tested for malaria and 10,870 vouchers were issued. 7416 randomly-selected
participants with recent fever from all 32 clusters were surveyed. The
majority of recent fevers were in children under 18 years (62.9%, n=4653).
The gender of enrolled participants was balanced in children (50.0%,
n=2318 v 50.2%, n=2335), but more adult women were enrolled than men
(78.0%, n=2139 v 22.0%, n=604). At baseline, 67.6% (n=1362) of
participants took an ACT for their illness and 40.3% (n=810) of all
participants took an ACT purchased from a retail outlet. At 12 months,
50.5% (n=454) in the intervention arm and 43.4% (n=389) in the control arm
had a malaria diagnostic test for their recent fever (Adjusted Risk
Difference=9 percentage points [pp], 95%CI: 2-15pp, p=0.015; Adjusted Risk
Ratio=1.20, 95%CI:1.05-1.38, p=0.015). By 18-months, the ARR had increased
to 1.25 (95%CI:1.09-1.44, p=0.005). Rational use of ACTs in the
intervention area increased from 41.7% (n=279) at baseline to 59.6%
(n=403) and was 40% higher in the intervention arm at 18 months (Adj RR
1.40, 95%CI: 1.19-1.64). While intervention effects increased between 12
and 18 months, we were not able to estimate longer-term impact of the
intervention and could not independently evaluate the effects of the free
testing and the voucher on uptake of testing. Conclusions:
Diagnosis-dependent ACT subsidies and community-based interventions that
include the private sector can have an important impact on diagnostic
testing and population-wide rational use of ACTs. Targeting of the ACT
subsidy itself to those with a positive malaria diagnostic test may also
improve sustainability and reduce the cost of retail sector ACT subsidies.