Cantril Ladder or Overall Life Satisfaction? Comparing 0–10 Summary Indicators of Adolescent Wellbeing

Despite widespread use in wellbeing research, little is known about whether the Cantril Ladder (CL) and Overall Life Satisfaction (OLS) questions (both 0–10 single-item indicators) capture the same construct in adolescent populations.We analysed data from 6,445 students aged 11–18 in 38 International Baccalaureate schools across 24 countries. We compared CL and OLS using descriptive statistics, confirmatory factor analysis (CFA), regression models, and subgroup analyses.Mean CL and OLS scores were similar, but response distributions differed: OLS showed more extreme values and negative skew. In a CFA including other life evaluation measures, both OLS and CL items loaded on a shared life evaluation latent factor, but OLS showed higher loadings. OLS also showed stronger predictive validity than CL across measures of life evaluation, affect, and eudaimonic wellbeing. Subgroup analyses revealed interpretive differences across age, gender, and language groups (English, Spanish, and French).Both CL and OLS are valid indicators of adolescent life evaluation, but they are not interchangeable. OLS may be preferable as a summary measure due to stronger predictive performance, while CL may offer more consistent subgroup comparability. Researchers should consider these trade-offs when selecting and interpreting single-item wellbeing measures.