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Health Equity: Full Day Kindergarten Programs


What the Task Force Found

About The Systematic Review

The Task Force finding is based on evidence from a systematic review published in 2010 (Cooper et al., 55 studies, search period through 2009). The search for more recent evidence (search period through March 2011) did not identify additional studies about full-day kindergarten programs. The systematic review team also reviewed studies of the long term effects of early childhood education to draw inferences about the possible long term effects of full-day kindergarten. The review was conducted on behalf of the Task Force by a team of specialists in systematic review methods, and in research, practice, and policy related to promoting health equity.


Children in low-income families often experience delays in language and other development by the age of three. Compensating for these delays before children begin regular schooling can be critical to providing them with equal opportunities for lifelong employment, income, and health.


Summary of Results

Short Term Effects

  • Full-day kindergarten led to statistically significant effects among children:
    • Improvement in scores on standardized achievement tests or assigned grades by the end of kindergarten or the beginning of first grade (50 studies). Compared with half-day kindergarten enrollees, math scores among full-day enrollees improved by 0.24 standard deviations (Cohen's d; 95% CI=0.06, 0.43), verbal scores by 0.46 standard deviations (Cohen's d; 95% CI=0.32, 0.61).
    • Increased ability to work and play with others—an indicator of social-emotional health (1 study; Cohen's d;=1.06; 95% CI=0.63, 1.49).
  • Early academic achievement is an established determinant of long-term academic and health-related outcomes; thus improvements in academic achievement among low-income and racial and ethnic minority children can be expected to improve their long-term health.

Long-Term Effects

  • In the Cooper et al. review, studies that considered whether full-day kindergarten had lasting effects showed inconsistent results by the time children reached the end of third or fourth grade.
  • A larger body of evidence including systematic reviews of the long term effects of early childhood education showed longer-term benefits associated with pre‑kindergarten educational programs. Greater benefits were seen when children went on to attend high quality primary schools as opposed to lower quality primary schools, emphasizing the importance of on-going school environments that support learning and development.

Summary of Economic Evidence

Six studies were included in the economic review. One study addressed the costs and benefits of full-day kindergarten versus half-day kindergarten; five studies provided information about costs; one study provided information about a single economic benefit and not about other potential benefits.

  • The six identified studies did not give a clear picture about costs beyond the broad finding that full-day kindergarten is relatively more expensive than half-day kindergarten. Additional evidence on the cost effectiveness of full-day kindergarten is needed.
  • Results from one study showed full-day kindergarten could be cost-beneficial if additional programs were undertaken to ensure maintenance of the short term academic gains. Researchers noted, however, that costs of additional programs not included in their estimates would have to be taken into account.
  • One study indicated substantial economic benefits of full-day kindergarten associated with the reduction of the proportion of children retained in class and required to repeat a grade.



  • While information on applicability of findings by race/ethnicity and SES was limited in the meta-analysis—perhaps because of stringent definitional criteria—other studies of full-day kindergarten generally report increased benefit for minority and low-income populations.
  • Programs were effective in both urban and non-urban settings.

Evidence Gaps

Each Community Preventive Services Task Force (Task Force) review identifies critical evidence gaps—areas where information is lacking. Evidence gaps can exist whether or not a recommendation is made. In cases when the Task Force finds insufficient evidence to determine whether an intervention strategy works, evidence gaps encourage researchers and program evaluators to conduct more effectiveness studies. When the Task Force recommends an intervention, evidence gaps highlight missing information that would help users determine if the intervention could meet their particular needs. For example, evidence may be needed to determine where the intervention will work, with which populations, how much it will cost to implement, whether it will provide adequate return on investment, or how users should structure or deliver the intervention to ensure effectiveness. Finally, evidence may be missing for outcomes different from those on which the Task Force recommendation is based.

Identified Evidence Gaps

  • The long terms effects of full-day vs. half-day kindergarten have not been well assessed, taking into account schooling subsequent to kindergarten as well as family and community environment.
  • Because low-income and minority children are at greater risk of educational challenges prior to entry into the school system, it is important to assess the differential effects of full-day kindergarten on low-income and minority children vs. higher income non-minority children.
  • Further studies of the cost-benefit ratio of full-day vs. half-day kindergarten are needed.

Study Characteristics

  • Included studies compared full-day kindergarten with either half-day kindergarten or alternating–day full-day kindergarten. Several studies compared half-day kindergarten with alternating-day full-day kindergarten and found no clear difference.
  • No randomized control studies were included in the review.
  • Among studies reporting program location, 69% were in urban locations, 31% in non‑urban locations.
  • Programs were more likely to be offered in the southern region of the U.S. than in other regions.
  • Full-day programs provide more instruction in math and reading as compared with half-day programs. Based on a national survey, FDK students were reported to receive 30-31% more instruction per day in math and reading than students in HDK (Walston & West, 2004).
  • Information on race and ethnicity was recorded in the meta-analysis if the population was reported to be "homogeneous." While criteria for this assessment are not given, if stringently applied, they may have excluded information in many studies.