The level of schooling or training a person has completed.Education, in the sense used in surveys and statistics, is the amount and kind of formal schooling a person has completed — for example, primary school only, secondary school, a bachelor's degree, or a doctorate. It is usually recorded as a category or as a number of years, and it is one of the most commonly collected pieces of information about people because it correlates with income, health, employment, and many other outcomes. In research it often appears as a control variable: when scientists compare groups, they check whether differences in education could explain part of the effect they are studying.
Systematic international classification of educational attainment grew out of work by UNESCO and other bodies in the twentieth century; the ISCED framework was first adopted in the 1970s and has been revised several times since.
Measurement is straightforward in principle: respondents are asked the highest level they finished, and answers are mapped onto a standard classification such as the International Standard Classification of Education (ISCED), which lets countries be compared. The complications are practical. Self-reports can be inaccurate, categories differ between countries and change over time, and 'years of schooling' treats a year in one system as equivalent to a year in another. Analysts therefore often use several measures and check whether conclusions hold under each.
Educational attainment is a standard variable in epidemiology, economics, and social science surveys, where it is used to adjust for socioeconomic differences between study groups and to track population trends over time.