Survey of Adult Skills 2023 Technical Report
The Survey of Adult Skills 2023 Technical Report, produced by the OECD as part of the Programme for the International Assessment of Adult Competencies (PIAAC), provides a comprehensive account of how adult literacy, numeracy, and adaptive problem-solving are measured across 31 countries. Published in 2025, the report explains the design of the second survey cycle, including sampling methods, test delivery on tablets, and the frameworks used to define the three skill domains. It also details the development of background questionnaires, scaling methods, and proficiency levels that allow results to be comparable with earlier international surveys of adult skills.
Beyond methodology, the report underscores the importance of these skills for individuals’ employability, wages, and lifelong learning, as well as for broader social and economic outcomes. It highlights how adaptive problem-solving was introduced for the first time, reflecting the growing need to understand how adults handle complex, changing information environments. Skills gaps remain wide across populations, and the technical foundations laid out in this report will enable policymakers to monitor them more accurately over time.
A significant focus is placed on ensuring comparability and fairness in measurement across diverse national and linguistic contexts. The report explains the translation and verification processes, cognitive testing, and field trial phases that safeguard the reliability of the survey’s instruments. It also addresses issues of non-response, weighting, and variance estimation, which are crucial for producing valid cross-country comparisons.
Looking ahead, the OECD stresses that the survey’s robust design and international comparability will be essential for guiding education and labour market policies. By linking the results of the second cycle with earlier assessments, the report strengthens the evidence base for policies to develop, activate, and better use adults’ skills, ensuring that countries can adapt to digitalisation, demographic change, and the demands of future work.
