Trait Questionnaires or Ambulatory Assessment? Predictive Validity of Within-Person Effects of Need Fulfillment on Well-Being

This work examines how between-person differences in within-person effects of the fulfillment of the needs for competence, relatedness and autonomy on well-being (= need effects) are associated with physical symptoms and dropout (intentions) out of tertiary education, and whether these associations vary by assessment method. Prior research suggests that experiences captured through ambulatory assessment predict physiological responses, while trait questionnaires reflect beliefs guiding behavioral intentions and choices. Using data from a 1.5 year measurement burst study with N = 897 young adults transitioning to postsecondary education, we applied linear multilevel models and multilevel survival analyses. Results showed that individuals with a stronger effect of daily competence satisfaction on daily well-being had more daily physical symptoms overall, and particularly after experiencing insufficient competence satisfaction. We found no further effects of experienced or perceived needs on physical symptoms, dropout intentions or dropout. Our findings suggest that assessing experienced need effects via ambulatory assessments vs. perceived need effects via trait questionnaires differ not only from each other but also with respect to their potential to predict future outcomes. Notably, predictive validity was weak and mainly limited to competence satisfaction.