Assessing affective states in domestic dogs through judgment bias tasks: a systematic review of methods, influencing factors, and welfare applications
Year: 2026
Type: review
Study design: Systematic Review
Abstract: Background Judgment bias tasks (JBTs) have emerged as a promising approach for assessing affective states in animals, including domestic dogs, by measuring optimistic or pessimistic responses to ambiguous stimuli as proxies for underlying emotion. Despite growing use, the canine evidence base had not been systematically evaluated. Methods We conducted a systematic review following PRISMA 2020 guidelines, searching Scopus and PubMed, with a supplementary search of Web of Science Core Collection. Thirty-two studies (15 experimental, 13 observational/quasi-experimental, 4 methodological) met the inclusion criteria. Experimental studies were appraised with the SYRCLE risk-of-bias tool. Findings were synthesized narratively, as methodological heterogeneity precluded meta-analysis. Results Five paradigm types were identified, but 28 of the 32 studies (88%) used the same spatial discrimination task; the four remaining paradigms were represented by one study each. JBTs showed sensitivity to some experimental manipulations, including oxytocin ( d = 2.16) and environmental enrichment (nosework, p < 0.01), while observational and quasi-experimental studies also reported associations between training method and JBT performance (e.g., aversive versus reward-based training: Z = −2.38, p = 0.017). However, validity and reliability concerns were pervasive: ceiling effects at ambiguous locations, confounding by spatial-learning ability, poor test–retest reliability, and absent protocol standardization. Convergence with independent welfare indicators was only partial. Conclusion JBTs are responsive to some affective manipulations and are associated with relevant welfare and experiential factors, but substantial validity and reliability limitations remain. Standardized protocols and multi-method validation are needed before JBTs can serve as field measures of canine welfare.
Source: Frontiers in Veterinary Science
Institutions: University of Pisa, University of Rome Tor Vergata
Language: English
Subfield: Animal Science and Zoology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W7223368404