Scenario 2

Background

You have been recruited by the National Malaria Control Programme (NMCP) of Tanzania to assist with study design. The NMCP is concerned about the potential spread of mutations that affect the performance of HRP2-based rapid diagnostic tests (RDTs). pfhrp2 deletions can cause false-negative results in HRP2-based RDTs. In the last few weeks, there have been anecdotal reports of RDT failures in border towns, particularly in the South Region. Additionally, there are concerns about the emergence of artemisinin resistance due to pfk13 mutations, as neighboring countries have reported detection of these mutations. Confirming whether these rare mutations are present in Tanzania is a priority for the NMCP. The NMCP plans to conduct a cross-sectional study to estimate the prevalence of pfhrp2 deletions and detect pfk13 mutations. The NMCP are also interested to know the prevalence of other drug resistance mutations, such as pfdhps, pfdhfr and pfcrt mutations so these are secondary outcomes of interest.

Your task

The NMCP has a budget of USD 250,000. There are four regions in Tanzania (North, South, East and West) each with 25 health facilities. From previous studies conducted by the NMCP, we know that the intra-cluster correlation is 0.01. Your job is to design a study powered for the following end-points:

  • Primary endpoints
    • Estimate the prevalence of pfhrp2 deletions causing false-negative RDTs
    • Detect pfk13 mutations associated with artemisinin resistance.
  • Secondary endpoint
    • Estimate the prevalence of pfdhps, pfdhfr and pfcrt mutations.

Each team member has key information on the epidemiological context, health facilities in each region, costing and sample size considerations (ICC, etc). Click on your role to access this information. Work in parellel (but together) to develop your study design!