Personality Change in the Light of Relationship Transitions in Partnered and Single Individuals: Study Protocol of a Prospective Measurement Burst Design

This protocol describes a research project investigating changes in individual differences in the context of relationship transitions in single and partnered individuals. While prior research has examined long-term personality change in the context of life events, this study takes a fine-grained, dynamic approach to capture short-term personality changes before, during, and after relationship transitions. The study integrates trait-level, state-level, and situational perspectives to examine how personality co-evolves with relationship transitions. By employing narrower assessment intervals and considering self-perceived event characteristics, this study aims to provide a comprehensive understanding of personality-change mechanisms in romantic relationships. The study employs a measurement-burst design over 2.5 years, following N = 1,781 participants aged 18–40 (mean age 26.5 years). Half of the sample started the study being single while the other half started in a relationship. Participants completed seven assessment waves at five-month intervals, each consisting of (a) global assessments at the start and end of each wave, and (b) a 3-day experience sampling phase in between. This design enables the investigation of selection effects (who experiences relationship transitions based on personality), anticipation effects (changes in personality before a transition), and socialization effects (changes in personality following relationship transitions). Additionally, by integrating situational context and subjective event characteristics, the research project aimed to address gaps in previous research on personality-situation interactions in relationship transitions. This research project is one of the first to systematically examine short-term personality dynamics in response to romantic relationship transitions. By capturing moment-to-moment changes, it advances research on personality change, relationship research, and life event perception.