Modernizing survey design: comparison of response patterns in Finnish National Surveys in 2020–2024

Abstract Background Self-administered survey questionnaires are essential in public health research. However, traditional health surveys face rising costs, and declining response rates, especially among youth. To address these challenges, innovative survey strategies are required. We assessed response patterns in surveys from 2020 to 2024, the effect of a push-to-web approach and the use of a graphical envelope. Methods We analysed the data from FinSote 2020 (n = 28,199), Healthy Finland 2022 (n = 28,154) and 2024 (n = 26,682) surveys in Finland. Adults aged 20+ were contacted four times via postal letter. Respondents could complete either an online or paper questionnaire. The oldest age group (75+, 2020 55+) received a paper questionnaire three times and the 20-54 age group only once. In 2022, the survey design was changed so that the 55-74 age group was sent a paper questionnaire twice and in 2024 only once. In 2024, we sent the first reminder letter in a graphical envelope to 50% (n = 9519) of Finnish speakers non-response aged 20-54 and white envelope to 50% (n = 9498) of them. Results The overall response rate ranged from 44-47 % in 2020 to 2024. Persons aged 75 + rarely responded to the online questionnaire, with less than 10 % responded online. In contrast, over 80% of respondents aged 20-54 completed the survey online. The largest increase was seen among those aged 55-74, rising from 19% to 60%, although their overall response rate slightly declined from 60 % to 53 %. Contrary to the hypothesis, no differences in response rates were observed between those who received a graphic envelope or a plain envelope in the 20-54 age group. Conclusions In population surveys, the push-to-web approach can boost online responses without greatly affecting response rates. However, omitting a paper option may lead to underrepresentation of older adults and biased results. More efforts are needed to modernize data collection to engage younger age groups in future surveys. Key messages • Using a push-to-web approach significantly increased online responses, providing a cost-effective opportunity for future population surveys, particularly among younger age groups. • The needs of different age groups must be considered when conducting a survey, such as the digital skills of older individuals and the low response rate among young people.