biostudies-literatureUnknown33Piseddu AParrots are popular companion animals but show prevalent and at times severe welfare issues. Nonetheless, there are no scientific tools available to assess parrot welfare. The aim of this systematic review was to identify valid and feasible outcome measures that could be used as welfare indicators for companion parrots. From 1,848 peer-reviewed studies retrieved, 98 met our inclusion and exclusion criteria (e.g. experimental studies, captive parrots). For each outcome collected, validity was assessed based on the statistical significance reported by the authors, as other validity parameters were rarely provided for evaluation. Feasibility was assigned by considering the need for specific instruments, veterinary-level expertise or handling the parrot. A total of 1,512 outcomes were evaluateAnimal welfare (South Mimms, England)e57https://www.ebi.ac.uk/biostudies/studies/S-EPMC11655281biostudies-literatureWhat we (don't) know about parrot welfare: Finding welfare indicators through a systematic literature review.PMC11655281van Zeeland YRRault JLPiseddu AfalseWhat we (don't) know about parrot welfare: Finding welfare indicators through a systematic literature review.Parrots are popular companion animals but show prevalent and at times severe welfare issues. Nonetheless, there are no scientific tools available to assess parrot welfare. The aim of this systematic review was to identify valid and feasible outcome measures that could be used as welfare indicators for companion parrots. From 1,848 peer-reviewed studies retrieved, 98 met our inclusion and exclusion criteria (e.g. experimental studies, captive parrots). For each outcome collected, validity was assessed based on the statistical significance reported by the authors, as other validity parameters were rarely provided for evaluation. Feasibility was assigned by considering the need for specific instruments, veterinary-level expertise or handling the parrot. A total of 1,512 outcomes were evaluate2024-01-01T00:00:00Z20242026-05-29T14:36:54.805Z2025-04-06T22:15:48.76ZS-EPMC116552813970322210.1017/awf.2024.61