Dec 9, 2005
If a high-quality, universal preschool program for four-year-olds were implemented in San Diego County, each annual cohort of participants would realize the following benefits, among others, over the course of their childhood and adolescent years:
These reductions range from 5 to 17 percent of what would occur without the universal preschool program. The improvements are associated with substantial financial benefits to California taxpayers, preschool participants, and California society at large.
Policymakers and the public are interested in the potential costs and benefits of making high-quality preschool available to all children at some point before kindergarten entry. In a prior study, RAND researchers estimated that a high-quality, one-year, voluntary, universal preschool program in California could generate for California society $2.62 in benefits for every dollar of cost. For each annual cohort of four-year-olds (approximately 550,000 children), the study estimated that California society would receive $2.7 billion in present-value net benefits.
Benefits for each cohort of four-year-olds were also estimated in nonmonetary terms. These benefits include nearly 14,000 fewer children ever retained in grade; 9,100 fewer children ever using special education; 10,000 fewer high-school dropouts; 4,700 fewer children with a substantiated case of abuse or neglect; and 7,300 fewer children with a juvenile petition (i.e., a juvenile arrest that leads to a court filing). These results assume that 70 percent of the four-year-olds, or 385,000 children, participate in the preschool program.
These estimates pertain to the state of California as a whole. We report here a follow-up study in which the statewide analysis was extended to generate estimates at a more localized level. Specifically, the study estimated the effects of a high-quality, one-year, universal preschool program for the largest California counties and for several groups of California counties. Estimated effects included reductions in grade repetition, use of special education, high-school dropout rate, child abuse and neglect, and juvenile crime.
This research brief focuses on the results for San Diego County. Companion research briefs focus on analogous findings for Los Angeles and Orange counties, as well as for five county groups: Bay Area (Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Santa Cruz, and Sonoma counties); Capital Region (El Dorado, Placer, Sacramento, Solano, and Yolo counties); Central Coast (Monterey, San Benito, San Luis Obispo, Santa Barbara, and Ventura counties); Central Valley (Fresno, Kern, Kings, Madera, Merced, San Joaquin, Stanislaus, and Tulare counties); and Inland Empire (Riverside and San Bernardino counties).
The county-level estimates of the effects are based on an extension of the methodology employed in RAND's statewide analysis. The approach assumes a high-quality preschool program available to all California four-year-olds on a voluntary basis. Class size, staff-to-child ratio, and teacher qualifications are assumed to be consistent with research-based quality standards. Notably, these standards exceed those required for public preschool programs in California, such as Head Start and the California state preschool program. (If a less expensive program with lower standards were implemented, it is reasonable to suppose that benefits would be smaller than those cited here.)
The disaggregated analysis accounts for population size differences across California counties as well as differences in the size of the at-risk population and in current preschool participation rates. County-level data are drawn from a variety of sources including California Department of Finance population projections; census data on preschool participation rates; and other California data on baseline education, child abuse and neglect, and juvenile crime.
To determine which effects would be realized by a universal preschool program and the magnitude of those effects, RAND drew upon scientific evidence of the effects of high-quality preschool on disadvantaged children. The effects measured in the scientific studies were adjusted downward to account for the broader population of children served and for benefits received by those children already attending quality preschool programs. The adjustment factor varied for each county and county group, depending on county income levels and current preschool participation rates.
|Reduction in the number of children ever retained in grade||1,005||13,808|
|Reduction in the number of children ever using special education||666||9,146|
|Reduction in the number of child-years of special-education use||4,569||62,764|
|Reduction in the number of high-school dropouts||731||10,042|
|Increase in the number of child-years of education||2,154||29,589|
|Reduction in the number of children with substantiated reports of child abuse or neglect||346||4,752|
|Reduction in the number of children with juvenile petitions (court filings)||535||7,352|
|Reduction in the number of children with juvenile petitions (court filings) for violent offenses||411||5,649|
|Reduction in the number of juvenile petitions (court filings)||2,154||29,589|
NOTE: Effects are those of a high-quality, one-year, universal, voluntary preschool program.
San Diego County is projected to have an average of nearly 44,000 four-year-olds each year over the next decade. The table shows the improvements in measures of education, abuse and neglect, and juvenile crime that San Diego County can expect for each cohort of four-year-olds that would participate in the program. (Results are also shown for California as a whole.) Each of these outcomes is a cumulative measure, capturing changes for each annual cohort of participants from the end of preschool to age 18. For example, if the 44,000 four-year-olds participate in a high-quality, universal preschool program at a 70-percent rate, almost 700 fewer children will ever use special education as they work their way through elementary, middle, and high school.
The benefits would be realized at different times in the future. The grade-retention and special-education improvements can occur throughout the K–12 years, while the reduction in dropouts is realized at approximately age 18, i.e., 13 years after the universal preschool program ends. Likewise, most of the juvenile crime improvements will be realized during the adolescent years.
To put into perspective the size of these effects for San Diego County (and California as a whole), the figure shows the estimated improvements in percentage terms, relative to a baseline that measures what the outcomes would have been in the absence of a universal preschool program. The percentage effects were calculated for seven of the nine measures. (Such estimates were not possible for grade repetition and violent juvenile crime because of data limitations.) For example, the reduction of almost 700 children who ever use special education represents 5–7 percent of the total number of such cases as projected without the universal preschool program. The range (5–7 percent) reflects different assumptions used to derive the baseline level.
The estimated percentage effects for San Diego County are generally a few percentage points below those estimated for California as a whole. The reason is that the county has a somewhat more advantaged population than the state as a whole, so the effects of the preschool program are slightly attenuated compared to the statewide average. The percentage effects range from a 5-percent reduction in children ever abused or neglected to a 17-percent reduction in the number of juvenile petitions.
While some of the improvements may appear to be modest in percentage terms, it is important to note that they are associated with substantial financial benefits that accumulate with the passage of time. The earlier statewide RAND study estimated, for example, that each year of special-education use that is avoided saves California taxpayers $8,421. An average high-school graduate, compared with an average high-school dropout, earns an additional $132,000 (present value) by age 65. The California public sector benefits from the higher lifetime earnings in the form of higher tax revenue of more than $5,000 (present value) for each additional high-school graduate. In addition, a typical case of child maltreatment that is prevented saves $5,174 in California public-sector funds plus an additional $5,079 in tangible costs to victims. Finally, each juvenile petition that is avoided saves California taxpayers an average of $9,204 in costs through the juvenile justice system and $12,873 in tangible victim costs. These figures for child maltreatment and juvenile crime do not account for any intangible victim costs (e.g., pain and suffering). Furthermore, the crime costs do not account for any subsequent lifetime savings to the criminal justice system and crime victims as a result of preventing adult crime.
The estimates presented above for San Diego County and for California are subject to several sources of uncertainty. While the study did not calculate error bands around the estimates, the estimates should be viewed as approximations of the expected size of the effects.
Despite the uncertainty in the estimates, the county-level results presented here can provide relevant local perspective for public and private decisionmakers considering investments in a high-quality, universal preschool program in California. The findings provide a sense of the likely magnitude of the benefits of universal preschool in terms of key measures of the well-being of children, measures that also have favorable economic consequences for the public sector and for private individuals.