Cost comparison of five Australasian obesity prevention interventions for children aged from birth to two years.

Background: In the absence of rigorous evidence of cost-effectiveness for early childhood obesity prevention interventions, the next-best option may be for decision-makers to consider the relevant costs of interventions when allocating resources.

Objectives: This study aimed to estimate systematically the cost of five obesity prevention interventions in children aged 0-2 years, undertaken in research settings in Australia and New Zealand.

Methods: A standardised costing protocol informed the costing methodology, ensuring comparability of results across interventions. Micro-costing was undertaken, with intervention costs defined from the funder perspective and valued in 2018 Australian dollars using unit costs from the trials or market rates.

Results: Interventions varied widely in their resource use. The total cost per participant ranged from $80 for the CHAT SMS intervention arm (95% UI $77-$82) to $1135 for the Healthy Beginnings intervention (95% UI $1059-$1189). Time costs of personnel delivering interventions contributed >50% of total intervention costs for all included studies.

Conclusions: An understanding of the costs associated with intervention delivery modes is important, alongside effectiveness. Telephone delivery may include unexpected costs associated with connection to intervention participants at convenient times. A SMS-based intervention had the lowest delivery cost in this study.