Cost Effectiveness of Early Childhood Interventions to Enhance Head Start: Evidence from a Randomized Experiment

We evaluated the cost effectiveness of instructional coaching and parent coaching models in Head Start using a randomized trial. The study design allowed us to compare the individual effects of each coaching model as well as their combined effect on student outcomes. Teachers receiving instructional coaching improved their use of language and literacy instructional practices, while parents receiving family coaching showed increases in numerous responsive parenting behaviors associated with positive child outcomes. Instructional coaching was more cost effective than parent coaching in promoting these evidence based practices. However, only the parent coaching model showed significant impacts on student outcomes. Parent coaching alone with no instructional coaching was therefore the most cost effective of the three treatment conditions for improving student outcomes. COST EFFECTIVENESS OF EARLY CHILDHOOD INTERVENTIONS 2 Cost Effectiveness of Early Childhood Interventions to Enhance Head Start: Evidence from a Randomized Experiment Early childhood interventions such as preschool programs are one of the most effective means for improving school readiness and students' long term outcomes, particularly for marginalized youth (Barnett, 2007; Dynarski, Hyman Schanzenbach, 2013; Heckman, Moon, Pinto, Savelyev Yavitz, 2010) Many policymakers have called for the provision of universal pre kindergarten (e.g. Obama, 2013) The U.S. Congress commissioned a national study of the federal Head Start preschool program as part of its reauthorization in 1998 to determine the effect on children's short and long term outcomes. One of the key findings of the Head Start Impact Study is that while the Head Start program provides benefits for enrollees, there is substantial variation in program quality (U.S. Department of Health and Human Services, 2010) Full day service and frequent home visiting are two general characteristics linked to higher quality (Walters, 2015) although adding these practices can be expensive and expanding funding for Head Start often faces political challenges (Lachman, 2014) While many studies examine the effects of add on preschool interventions, very few rigorously analyze costs (Levin, 2001) Thus a vital and overlooked role of research on preschool programs is to identify cost effective means for improving the effectiveness of Head Start and other early childhood programs. The following study compared the cost effectiveness of interventions that combine instructional coaching for preschool teachers with family coaching for the parents of students enrolled in preschool. We analyzed two widely implemented interventions, the Texas Early Educator Model (TEEM) and the Play and Learning Strategies (PALS) model. The design of our study allowed us to test both the individual effects of these interventions and their combined impacts on a set of cognitive and non cognitive student outcomes. The TEEM intervention involves trained coaches collaborating with Head Start teachers and directors to implement an COST EFFECTIVENESS OF EARLY CHILDHOOD INTERVENTIONS 3 evidence based instructional program with developmentally appropriate lesson plans and teaching strategies. Similarly, the PALS intervention is aimed at improving responsive parenting techniques by matching family coaches with parents over the course of a school year. We randomly assigned the TEEM intervention to teachers across 77 Head Start centers over a three year period (2009 10 to 2011 12) Within classrooms, students were then randomly assigned to have their parents receive PALS. A total of 434 students were thus randomly assigned to both the TEEM and PALS interventions, just one of these interventions, or the control group. We tracked a wide array of pre and post intervention outcomes for teachers, parents, and students. Finally, we conducted a rigorous cost analysis of each intervention using the methods laid out in Levin and McEwan (2001) Our study addressed the following three research questions: What is the individual impact of the TEEM and PALS interventions and are there additional benefits for students who receive both interventions? What are the costs associated with each of the two interventions? Which of these three treatment conditions is the most cost effective? We found that both TEEM and PALS led to positive and significant improvements across a range of intermediate outcomes. The teacher coaching model showed substantially larger effect sizes on instructional practices than the parent coaching model had on measures of evidencebased parenting practices. Cost effectiveness ratios suggest that TEEM was more cost effective than PALS at increasing the use of evidence based teacher and parent practices. Analyses of student outcomes showed that students assigned to the PALS only condition improved on several cognitive and non cognitive outcomes, relative to the control group. However, the addition of TEEM instructional coaching to the PALS intervention did not significantly alter outcomes. Indeed, students assigned to TEEM only did not make significantly larger gains in outcomes COST EFFECTIVENESS OF EARLY CHILDHOOD INTERVENTIONS 4 compared to a business as usual control group. Although implementation of PALS required far greater costs than the TEEM intervention, we conclude that PALS was the most cost effective of the three treatment conditions tested. Based on prior analyses of the overall cost effectiveness of Head Start (e.g. Puma et al. 2012;  2008) implementing PALS in Head Start centers would increase the cost effectiveness of Head Start by approximately seven percent. The study's findings have important policy implications for enhancing the impact of Head Start. Instructional coaching programs are far less costly than home visit programs, but may not produce any positive effects on students. Conversely, although one on one parent coaching models are expensive, their impact may warrant the cost. The study also reveals critical questions for future research. Would more intensive investment in teacher coaching improve Head Start teachers' instructional quality enough to positively impact students? Is the effect of home visit programs such as PALS large enough to justify the significant cost, relative to other potentially effective interventions for improving early childhood outcomes? In the balance of this paper, we review relevant background research and the policy context, provide greater detail on the experimental design of our study, our analytic approach, and findings, and we conclude with further discussion and policy implications.  A large body of research examines the effectiveness of preschool, which we review below. We then discuss prior research on early childhood interventions that draws on cost analysis, explore how these studies contribute to policy decision making, and explain how our study addresses gaps in this research. We provide greater detail on the TEEM and PALS interventions and review past research on their impacts on teachers, parents, and students. Finally, we offer a rationale for implementing these two interventions simultaneously and COST EFFECTIVENESS OF EARLY CHILDHOOD INTERVENTIONS 5 present our hypotheses of their individual and synergistic effects on students. The Impacts of Early Childhood Education There is growing consensus among researchers that providing young children with highquality classroom experiences prior to entering the K 12 public school system is one of the best approaches to narrowing educational opportunity and achievement gaps (e.g. Heckman et al. 2010) Research finds substantial positive social benefits of preschool programs that far outweigh the social costs (e.g. Barnett, 1985) For example, a randomized experiment of the High/Scope Perry Preschool Project involving 123 children in the 1960s found significant benefits of the program by age five that persisted well into adulthood (Schweinhart et al. 2005;  1997) A similar program, the Carolina Abecedarian Project has demonstrated positive long term effects associated with intensive early childhood interventions including frequent home visits and full day preschool (Campbell Ramey, 1995; Campbell et al. 2014) Unfortunately, many of the existing state and federal preschool programs do not always provide high enough quality learning experiences to adequately prepare underprivileged students for kindergarten (e.g. Burchinal, Kainz Cai, 2011; Wong, Cook, Barnett Jung, 2008) In the three subsections below we discuss factors associated with preschool effectiveness, provide greater detail on definitions of school readiness, and describe a theoretical basis for providing complementary interventions at home and at school. Exploring variation in preschool effectiveness. Prior research has identified significant variation in Head Start program effectiveness (Puma et al. 2012) Researchers have leveraged available data to identify the characteristics of high quality programs (Garces, Thomas Currie, 2002; Deming, 2009; Peck Bell, 2014; Puma et al. 2012) Drawing on the analysis from the COST EFFECTIVENESS OF EARLY CHILDHOOD INTERVENTIONS 6  (2015) found that across 353 Head Start centers, full day service (as opposed to half day) and frequent home visits are most predictive of success, while other inputs typically thought to enhance preschool including High/Scope curriculum, teacher experience, and class size were unrelated to outcomes. However, two thirds of the variation in Head Start effectiveness could not be explained with the available data. Importantly for our study, Walters did not have information on teachers' access to professional development or coaching, or on the quality of and practices used during home visits. Other studies confirm that two broad characteristics linked to early child