Background

Well-being is often considered a relatively stable trait and is assessed with questionnaires at a single time point or across multiple longitudinal waves. However, like many complex human traits, feelings of well-being fluctuate over the day or week and across contexts. In addition, there are individual differences in these fluctuations, some people show relatively stable levels of well-being over time and across contexts, while others fluctuate a lot. 

Aims

Using real-time data in twins, we aim to investigate the causes of individual differences in daily, weekly and seasonal patterns of well-being and the interaction with the environment.

Method

We invite a large sample of adult twin pairs (n=1500 participants, 300 monozygotic (MZ) twin pairs and 450 dizygotic (DZ) twin pairs) to participate in an Ecological Momentary Assessment (EMA) study for 7 consecutive days, 4 times a year (each season). The EMA approach includes eight assessments of well-being, whereabouts, activities, and social interactions per day via questionnaires on the smartphone of participants. In addition, we continuously collect data on the (social) environment, phone use and physical activity using passive sensing.

Results & Conclusion

This genetically informative design and combination of active and passive data results in a large dataset and can lead to new insights about individual differences in well-being and what makes people happy. We investigate the heritability of momentary well-being and well-being fluctuations using the difference in genetic overlap of MZ twins and DZ twins and investigate the interaction between momentary well-being and environmental variables, social contact, phone use and physical activity, taking into account individual differences.