Meeting the WHO 24-h guidelines among 2-6-year-old children by family socioeconomic status before and during the COVID-19 pandemic: a repeated cross-sectional study.

Background: The World Health Organization (WHO) has developed guidelines for 24-h physical activity (PA), sedentary behaviour and sleep for young children. Lower socioeconomic status (SES) has been linked to a lower likelihood of meeting these guidelines. The outbreak of the novel coronavirus disease (COVID-19) raised concerns about young children's opportunities to meet the guidelines. The study focused on the prevalence of meeting the WHO's 24-h guidelines on screen time (ST), PA and sleep among 2-6-year-old children, in association with family SES, before COVID-19 outbreak in 2019, and during the pandemic in 2020 and 2021 in Finland. Methods: Data were collected at three timepoints by an online survey through day-care centres. Meeting the WHO 24-h guidelines was defined for each behaviour, from a parent-reported seven-day recall of a typical day on weekdays and weekend days and adapted to the national context. Children were considered to meet the ST guideline if they had maximum of 60 min of ST, the PA guideline if they had minimum of 60 min of outdoor PA, and the sleep guidelines if they had minimum of 11/10/9 h (2/3-5/6 years) of good or very good quality sleep. Binary logistic regression models were used to examine the odds ratios of meeting the guidelines. Results: The prevalence of meeting the ST guideline was highest before the COVID-19 pandemic in 2019. The PA guideline was most met during the strict pandemic restrictions in 2020. Children from higher SES families were more likely to meet the ST and sleep duration guidelines either on weekdays or weekends. The PA guideline was met more on weekdays by children whose parents had lower education levels at all timepoints. In 2020, sleep quality guideline was less likely met by children with parents with the highest education levels. Conclusion: Higher SES may increase the odds of young children meeting the ST and sleep duration guidelines, but the results are more complex regarding PA and SES. The impact of the COVID-19 pandemic on ST, outdoor PA, and sleep of young children varied by family SES, and further research is recommended to identify causality of these relationships. Supplementary Information: The online version contains supplementary material available at 10.1186/s44167-022-00010-4.