Applicability of STOPP/START prescribing criteria in integrated Swedish administrative health registries and a Swedish population-based cohort.

The applicability of the STOPP/START criteria in observational studies seems to have decreased in more recent versions of the tool. Population-based studies with comprehensive clinical assessments may offer higher applicability compared to studies based on administrative data. Future versions of the STOPP/START criteria should prioritise clear and unambiguous definitions to improve their applicability in research and promote result generalisability and comparability.