Small island developing states (SIDS) are vulnerable to the ill-health effects associated with unabated atmospheric warming driven by larger, more developed countries. Hence, the health-centered focus of the Lancet Countdown on Health and Climate Change has immense value for SIDS.

Given resource constraints and data limitations across the SIDS region, the inaugural 2024 SIDS report of the Lancet Countdown required a method of singling out the most regionally relevant indicators from 47 Lancet Countdown global indicators. A two-stage semi-qualitative method was designed for this purpose.

The evaluation stage involved identifying two indicator sets from stakeholder consultation ( n = 32) and a multi-criteria assessment ( n = 11). Using both sets of indicators, only 11 met the criteria of being regionally representative and relevant, further confirming data limitations. To adjust for this challenge, 14 indicators were added to the final list based on relevance. Therefore, 25 Lancet Countdown indicators were selected for the 2024 SIDS report of the Lancet Countdown on Health and Climate Change. To further prioritize the wide range of evidence from these indicators, a qualitative multiplication matrix was used to define relationships between regional data coverage and differences from global benchmarks. Six indicators marked successes in adaptation, and 14 evidenced negative implications compared to global benchmarks.

The impact of heat on physical activity, food security, and economic development was of critical regional importance, as was the need for more research. The study identified critical areas where urgent climate action is needed, emphasizing the need for increased research and data collection in SIDS.