Costing interventions in the field: preliminary cost estimates and lessons learned from an evaluation of community-wide mass drug administration for elimination of soil-transmitted helminths in the DeWorm3 trial

Abstract

Objective: To present a costing study integrated within the DeWorm3 multi-country field trial of community-wide mass drug administration (cMDA) for elimination of soil-transmitted helminths.

Design: Tailored data collection instruments covering resource use, expenditure and operational details were developed for each site. These were populated alongside field activities by on-site staff. Data quality control and validation processes were established. Programmed routines were used to clean, standardise and analyse data to derive costs of cMDA and supportive activities.

Setting: Field site and collaborating research institutions.

Primary and secondary outcome measures: A strategy for costing interventions in parallel with field activities was discussed. Interim estimates of cMDA costs obtained with the strategy were presented for one of the trial sites.

Results: The study demonstrated that it was both feasible and advantageous to collect data alongside field activities. Practical decisions on implementing the strategy and the trade-offs involved varied by site; trialists and local partners were key to tailoring data collection to the technical and operational realities in the field. The strategy capitalised on the established processes for routine financial reporting at sites, benefitted from high recall and gathered operational insight that facilitated interpretation of the estimates derived. The methodology produced granular costs that aligned with the literature and allowed exploration of relevant scenarios. In the first year of the trial, net of drugs, the incremental financial cost of extending deworming of school-aged children to the whole community in India site averaged US$1.14 (USD, 2018) per person per round. A hypothesised at-scale routine implementation scenario yielded a much lower estimate of US$0.11 per person treated per round.

Conclusions: We showed that costing interventions alongside field activities offers unique opportunities for collecting rich data to inform policy toward optimising health interventions and for facilitating transfer of economic evidence from the field to the programme.

Trial registration number: NCT03014167; Pre-results.

Keywords: health economics; health policy; infection control; infectious diseases; public health.

Conflict of interest statement

Competing interests: None declared.

© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ.

Figures

Figure 1

Integration of costing study within the DeWorm3 trial research activities. The figure illustrates key surveys (top blue panel) and implementation science (IS) studies (bottom green panel) conducted along community-wide MDA in the DeWorm3 trial. It maps cost-effectiveness (to which costing contributes) within the IS research and highlights the contribution of other studies to costing and broader economic research agenda of the project. For further details refer to online supplemental table S1. Figure adapted from presentation by Means et al. MDA, mass drug administration; IEC, information, education and communication materials; STH, soil-transmitted helminths.

Figure 2

Routine financial reporting at India DeWorm3 trial site. The figure illustrates the flow of funds and financial reporting at India DeWorm3 trial site. Project’s grants manager—centre green box—is the focal point through which all country funds supporting the trial flow. For each project level the diagram shows staff responsible for dispersing funds (left) and gives examples of some of the resource line items that are purchased/consumed/recorded at that level (right panels). Bottom row—field site—additionally highlights itemised tracking of expenditures related to field worker per-diems and fuel (important cost driver of mass drug administration activities). PI, principlal investigator.