Early Interventions for Young Children High in Behavioral Inhibition: Effects on Early Childhood Irritability

Irritability, or the tendency to experience negative affect and temper outbursts, is commonly endorsed in youth with anxiety disorders. Irritability and anxiety predict one another in cross-sectional and longitudinal studies and share neural circuitry, suggesting potential benefit from shared treatment components. However, the benefits of anxiety treatments for irritability have not been examined in younger children, which may aid in early intervention efforts. This secondary data analysis examined intervention effects on irritability at post-treatment and one-year follow-up utilizing data from a randomized-controlled trial comparing the Turtle Program (“Turtle”) and Cool Little Kids (CLK) in a sample of 151 3–5-year-old children high in behavioral inhibition. Turtle and CLK both contain parent management training and cognitive-behavioral therapy components, however, Turtle also contained in-vivo coaching and exposure practice in session with parents and peers. Turtle and CLK groups did not significantly differ in baseline irritability or clinician-rated anxiety, depression, and attention-deficit/hyperactivity disorder (ADHD) symptoms. Saturated path models with robust standard errors using the lavaan package in R were conducted to test the main effect of treatment condition on irritability at post-treatment and one-year follow-up. Separate models were conducted to control for clinician-rated anxiety, depression, ADHD symptoms (Clinician Severity Ratings; CSR), and for parent-reported Child Behavioral Checklist (CBCL) internalizing and externalizing symptoms to assess specificity of results. Paired-samples t-tests were conducted to test whether irritability shifted within treatment group from pre- to post-treatment and one-year follow-up. Sensitivity analyses were conducted to investigate whether change in irritability was predicted by changed in predictors of interest. Children in Turtle demonstrated significantly lower irritability compared to those in CLK at post-treatment, but not at one-year follow-up. These results were consistent when accounting for clinician-rated and parent-reported comorbidity and when tested within treatment group. Furthermore, changes in ADHD, internalizing, and externalizing symptoms predicted changes in irritability from pre- to post-treatment. Results suggest potential treatment components such as enhancement of parent–child relationship, in-vivo parent coaching and exposure practice, and emotion socialization within Turtle may be particularly useful in reducing child irritability short-term. Results were consistent across clinician-rated severity and parent-rated symptom questionnaires. These findings highlight the potential utility of treatment components in early interventions to target irritability in young children high in BI.