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

Background : 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 traits and states co-evolve 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. Methods : The study employs a prospective measurement-burst design over 2.5 years, following N = 1,876 participants aged 18–40 (mean age 26 years). Half of the sample started the study being single while the other half was in a relationship at baseline. Participants completed seven assessment waves at five-month intervals, each consisting of (a) global trait surveys, (b) experience sampling over 3 days per wave, and (c) end-of-wave reflections on personality and well-being. This design enables the investigation of selection effects (who experiences relationship transitions based on individual differences), anticipation effects (changes in individual differences before a transition), and socialization effects (changes in individual differences 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. Discussion : 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. The study contributes to the broader debate on how personality traits, states, and situations dynamically interact over time.