Validity of self-reported educational attainment collected as part of a telephone interview in a Norwegian dietary...

Self-reported educational attainment is a much-used variable in research, but few studies have addressed the validity of this information. This study assesses the criterion validity of self-reported educational attainment from a telephone interview by comparing it with registry-based data from Statistics Norway.

Self-reported educational attainment was collected from 348 persons aged 18-80 years residing in Norway as part of a dietary study involving two 24-hour recalls conducted over the telephone during the spring of 2021. Information about officially registered educational attainment from Statistics Norway was later obtained for the same participants, and information from both sources was compared for 344 participants.

When dividing the participants into three educational groups, 77 % were classified in agreement with the officially registered educational attainment by self-report with regard to educational attainment. Twenty percent overreported their own educational attainment, while only 3% underreported. When dividing the participants into only two educational groups according to whether they had university/college education or not, 86% were in agreement with the officially registered educational attainment, 12% overreported their educational attainment and 2% underreported.

The majority of participants were classified in agreement with the officially registered educational attainment by self-report, but overreporting was more common than underreporting. These results should be taken into consideration when using self-reported educational attainment in research.