Towards a stronger link between PISA and PIAAC: Two assessments, one story?

How closely do the skills measured at age 15 predict the skills observed later in adulthood? This paper examines the relationship between the OECD's Programme for International Student Assessment (PISA) and the Programme for the International Assessment of Adult Competencies (PIAAC), drawing on newly available PIAAC Cycle 2 data. A series of country-level comparisons are used to explore the extent to which performance in reading/literacy and mathematics/numeracy aligns across the two assessments when viewed from different analytical perspectives, such as contemporaneous comparisons of PISA and PIAAC results, comparisons of matched pseudo-cohorts and comparisons of performance trends over time. The paper considers possible reasons for the similarities and differences between the results of both assessments, such as variations in assessment frameworks, target populations, sampling methods, testing conditions, motivation of respondents, and opportunities for developing skills throughout life. While PISA and PIAAC provide broadly consistent signals about national skill levels, the paper argues that differences in what and whom they measure, as well as in the contexts in which assessments are administered, limit direct comparisons.