This publication is intended to provide guidance as to the methodology used during the data collection for each indicator of Education at a Glance 2023, the references to the sources and the specific notes for each country.

The publication follows the structure of the Education at a Glance 2023 as follows:

Chapter 1 provides the sources, methodologies and technical notes for Chapter A - The output of educational institutions and the impact of learning – which focuses on various outcomes of education, including: educational attainment; transition from education to work; adult education and learning; employment, unemployment and earnings; and social outcomes, such as perception of democracy, civic engagement or privacy of personal data on Internet. The chapter also includes information on the standard errors for data on educational attainment and labour market status and the actual earnings data per country.

Chapter 2 provides the sources, methodologies and technical notes for Chapter B - Access to education, participation and progression – and covers the full education system from early childhood to tertiary education. It provides information on the methodology used to calculate the indicators, as well as country-specific notes and sources of data collection on enrolment, new entrants and graduates.

Chapter 3 provides the sources, methodologies and technical notes for Chapter C - Financial resources invested in education – which offers a comprehensive and comparative analysis on education expenditure across OECD and partner countries, focusing on five aspects of educational spending: Financial resources invested in educational institutions, relative to the number of students (Indicator C1), and relative to national output (Indicator C2). The source of funds devoted to educational institutions (Indicator C3). Total public resources invested in education, both inside and outside educational institutions, relative to total government spending (Indicator C4). The factors that influence teachers’ salary cost (Indicator C7).

The indicator on tuition fees of tertiary students and the public support they receive (Indicator C5) and the indicator on the nature of spending on education (Indicator C6) were not included in Education at a Glance 2023 and therefore not covered in Chapter 3 either.

Chapter 4 provides the sources, methodologies and technical notes for Chapter D - Teachers, the learning environment and the organisation of schools – and focuses on instruction time in compulsory education (Indicator D1), salaries of teachers and school heads (Indicator D3), examinations and assessments of students (Indicator D6) and the characteristics of teachers in vocational programmes (Indicator D7). It provides information on the methodology used to calculate the indicator on student teacher ratio and class size, as well as country-specific notes and sources of data collection on personnel data.

For general information on methodology, please refer to the OECD Handbook for Internationally Comparative Education Statistics: Concepts, Standards, Definitions and Classifications