title: The trajectory of fidelity in a multiyear trial of the family check-up predicts change in child problem behavior.
abstract: OBJECTIVE
  Therapist fidelity to evidence-based family interventions has consistently been linked to child and family outcomes. However, few studies have evaluated the potential ebb and flow of fidelity of therapists over time. We examined therapist drift in fidelity over 4 years in the context of a Family Check-Up prevention services in early childhood (ages 2-5 years).
  
  
  METHODS
  At age 2, families engaging in Women, Infants, and Children Nutritional Supplement Program services were randomized and offered annual Family Check-Ups. Seventy-nine families with a child in the clinical range of problem behaviors at age 2 years were included in this analysis.
  
  
  RESULTS
  Latent growth modeling revealed a significant linear decline in fidelity over time (M = -0.35, SD = 0.35) and that steeper declines were related to less improvement in caregiver-reported problem behaviors assessed at ages 7.5/8.5 years (b = -.69, p = .003; β = -.95, 95% CI [-2.11, -0.22]).
  
  
  CONCLUSIONS
  These findings add to the literature concerning the need to continually monitor therapist fidelity to an evidence-based practice over time to optimize family benefits. Limitations and directions for future research are discussed.
authors.affiliation: Department of Psychology, Arizona State University.
authors.forename: Amanda
authors.initials: A
authors.lastname: Chiapa
authors.affiliation: Department of Psychology and Neuroscience, Baylor University.
authors.forename: Justin D
authors.initials: JD
authors.lastname: Smith
authors.affiliation: Department of Psychology, Arizona State University.
authors.forename: Hanjoe
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Psychology, Arizona State University.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Dishion
authors.affiliation: Department of Psychology, University of Pittsburgh.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Shaw
authors.affiliation: Department of Psychology, University of Virginia.
authors.forename: Melvin N
authors.initials: MN
authors.lastname: Wilson
mesh_terms: D002648:Child; D002653:Child Behavior Disorders / Q000517:prevention & control*; D002675:Child, Preschool; D005190:Family / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D016487:Parenting / Q000523:psychology*; D015397:Program Evaluation / Q000706:statistics & numerical data*