Stages of Change in fruit intake: a longitudinal examination of stability, stage transitions and transition profiles

The present study examined stability and transitions in Transtheoretical stages of change for fruit intake in an adult cohort of 735 individuals not exposed to a planned intervention. Six assessments took place within a four-month period with varying time intervals using electronic questionnaires, measuring fruit intake, stage of change and demographic characteristics. Precontemplation and maintenance were the most stable stages of change, while preparation was the least stable. Longer time intervals showed lower stability, but frequent stage transitions also occurred in shorter time intervals. Seven transition profiles were distinguished. Sequences within transition profiles mostly showed stage transitions to adjacent stages, independent of the interval duration. Differences in fruit intake, age, level of education and ethnicity were found between different transition profiles. Stability rates and most transition sequences largely support the Transtheoretical Model. Results indicating potential deviations from the model, e.g. short-term stage instability and stage transition profiles not in accordance with the Transtheoretical Model are discussed.