Some reflections on the use of composite indicators for measuring health achievements at the subnational level: insights from Portugal

The exigency of “leaving no one behind”, expressed in the 2030 UN Agenda for Sustainable Development, and the existence in some contexts, such as in Portugal, of new competences for local authorities, call for greater attention to the evaluation of policies and monitoring of results at subnational level. This paper scrutinizes the most critical issues in the construction of composite indicators that are intended to analyze health, as interpreted in the SDGs, at the subnational level. First, the main characteristics of the indicators selected by Statistics Portugal to cover Goal 3 will be analyzed. Then, the paper will examine the priorities to be considered during construction of composite indicators, that take into account the structure of the SDGs. A first element concerns the need to deepen the choice of the indicator set on which the composite indicator will be based. Data limitation and the exclusion of some contextual elements hamper the construction of meaningful composite indicators at the subnational level. It is also critical to examine the possible synergies and trade-offs between the various SDG indicators, which directly or indirectly refer to health, and adequately consider these relationships in the aggregation phase.