Table 4. Summary of limitations and its implications.

Limitation	Implication
Choice of comparator determined by the RCT	The RCT comparator, the ESoC, is not the status quo for treating perinatally depressed women in rural areas in South Africa. Normally, the most cost-efficient alternative (often the status quo) is selected as the comparator when conducting a CEA. This may limit the relevance of the findings to an academic audience rather than a broader one where policy decisions need to be based on more generalisable findings.
Outcomes measurements in RCTs are more detailed than in reality	This may lead to findings that overstate the intervention’s cost-effectiveness when implemented at a population level.
Protocol biases may impact both costs and outcomes	Although considerable effort will be made to determine the extent to which participant management and resource use in the RCT reflects practice in a non-research setting, it is inevitable that protocol biases are likely to influence the findings. As is the case when analysing the cost-effectiveness of all RCTs, such protocol biases limit the generalisability of the study findings.

CEAcost-effective analysisESoCenhanced standard of careRCTrandomised controlled trial