skip to main content
Washington State Institute for Public Policy
Back Button

Circle of Security - Parenting (COS-P)

Public Health & Prevention: Home- or Family-based
  Literature review updated June 2017.
Open PDF
Circle of Security – Parenting (COS-P) aims to help parents and caregivers provide a secure base and safe haven for their young children. COS-P uses stock video of parent-child interactions and manualized curriculum to teach parenting skills in a group setting. This 10-week program is delivered in a community setting by Head Start providers. In the included study, all children in treatment and comparison groups received standard Head Start services.

This program is an abbreviated version of the 20-week Circle of Security curriculum.

Meta-analysis is a statistical method to combine the results from separate studies on a program, policy, or topic in order to estimate its effect on an outcome. WSIPP systematically evaluates all credible evaluations we can locate on each topic. The outcomes measured are the types of program impacts that were measured in the research literature (for example, crime or educational attainment). Treatment N represents the total number of individuals or units in the treatment group across the included studies.

An effect size (ES) is a standard metric that summarizes the degree to which a program or policy affects a measured outcome. If the effect size is positive, the outcome increases. If the effect size is negative, the outcome decreases.

Adjusted effect sizes are used to calculate the benefits from our benefit cost model. WSIPP may adjust effect sizes based on methodological characteristics of the study. For example, we may adjust effect sizes when a study has a weak research design or when the program developer is involved in the research. The magnitude of these adjustments varies depending on the topic area.

WSIPP may also adjust the second ES measurement. Research shows the magnitude of some effect sizes decrease over time. For those effect sizes, we estimate outcome-based adjustments which we apply between the first time ES is estimated and the second time ES is estimated. We also report the unadjusted effect size to show the effect sizes before any adjustments have been made. More details about these adjustments can be found in our Technical Documentation.

Meta-Analysis of Program Effects
Outcomes measured No. of effect sizes Treatment N Adjusted effect sizes (ES) and standard errors (SE) used in the benefit-cost analysis Unadjusted effect size (random effects model)
First time ES is estimated Second time ES is estimated
ES SE Age ES SE Age ES p-value
Externalizing behavior symptoms 1 75 -0.079 0.294 4 -0.038 0.153 7 -0.079 0.787
Internalizing symptoms 1 75 -0.103 0.294 4 -0.075 0.231 6 -0.103 0.727

Citations Used in the Meta-Analysis

Cassidy, J., Brett, B.E., Gross, J.T., Stern, J.A., Martin, D.R., Mohr, J.J., & Woodhouse, S.S. (2017). Circle of Security-Parenting: A randomized controlled trial in Head Start. Development and Psychopathology, 29(2) 651-673.

For more information on the methods
used please see our Technical Documentation.