Preliminary Results On Change and Variability in Outcomes from an Intensive Daily Data Collection with Intervention Participants

Introduction: There is much to be learned about the course of change between pre and post assessment. Intensive daily data collected during the course of an intervention can elucidate the “black box” of how, when, and in what way interventions have an impact—revealing when outcomes change and the shape of change. Because the utility of this approach to program evaluation rests on there being change, fluctuation, and/or variability among participants during the course of an intervention, the first step in this research is to describe these aspects of the data.

Methods: Participants were parents randomized to intervention conditions in a trial with the Strengthening Families Program: For Parents and Youth 10-14 (SFP). Parents completed daily web-based surveys that assessed select outcomes 6 out of 7 days of each week of the intervention. Outcomes included: SFP-targeted parenting behaviors (3 items, support, guidance, anger management), mindful parenting (5 items), parent-youth affective quality (4 items), and youth-parent affective quality (4 items). All scales are averages of items rated from 0 to 100.

Preliminary Results: We will present the trajectories of change in outcomes using growth curve analyses. Preliminary data from this ongoing study show that there is improvement in 3 of the 6 measured outcomes as shown by significant linear fixed effects in random-intercept only models; for example, for each day after the first day of the study, parents report a 0.17 unit increase in youth-parent affective quality, t(699) = 3.55, p < .05. At the end of 7 weeks, that equates to about an 8-unit increase above the rating at the first day, which was an intercept of 69.78. Final analyses will extend previous findings to show the polynomial shape of change on multiple outcomes between pre and post assessment, when these effects are significant. We will also interpret indicators of variability—differences among time points for each person—and variation—differences among people in trajectories of change.

Conclusions: Conclusions will be drawn about the shape of change over the seven weeks of this intervention. Where applicable, we will draw conclusions about the trajectory of change for specific outcomes with regard to the timing of program content introduced throughout the sessions. Future research using this type of data may explore variables such as such as attitudes about the curriculum content and child behavior as within- and between-person predictors of outcome trajectories over time.