California Strong Start Index: Frequently Asked Questions

Using data that already exist for children and families, the California Strong Start Index summarizes, in a standardized way, the conditions into which children are born. It comprises a total of 12 variables that fall into four domains. A birth asset score is calculated by simply counting the number of assets present (0-12).

The California Strong Start indicators include:


  • Legal parentage established at birth
  • Born to non-teen parents
  • Born to parents with at least a high school diploma


  • Healthy birthweight
  • Absence of congenital anomalies, abnormalities, or complications at birth
  • Absence of transmissible (mother-to-child) infections


  • Access to and receipt of timely prenatal care
  • Receipt of nutritional services (WIC) if eligible
  • Hospital with high percentage of births with timely prenatal care


  • Ability to afford and access healthcare
  • Born to a parent with a college degree
  • Born to parents with employment history

A thorough review of the research literature confirmed that these indicators found on vital birth records could be treated as “assets” due to their relationship to child health and well-being outcomes. In addition, external validity checks confirm the Strong Start Index’s alignment with other notable indices (e.g., the Healthy Places Index (HPI) and the Human Development Index (HDI)) and correlation with actual client-level outcomes (e.g., death and child protection involvement within the first five years of life). For more information, please refer to the California Strong Start Index Documentation.

Strong Start scores are generated by summing the total number of assets (0-12) as coded from each child’s (de-identified) birth record.

The number and percentage of babies born with each individual asset (indicator) is presented at the state level in Table 3 of the California Strong Start Index Documentation for descriptive purposes, but the presence of any one discrete asset or domain should not be the focus. The Strong Start Index is unique in its ability to describe the constellation of resources available to individual children and families. Additionally, producing asset and/or domain scores alongside total scores for more local jurisdictions would result in widespread suppression in order to mitigate the risk of re-identification. For those reasons, the site highlights total Strong Start Index scores.

The Strong Start Index is unique in its sole reliance on administrative birth records. Unlike other indices, it has the ability to provide recent, specific, holistic, and asset-focused information about cohorts of children born in California. These data can develop a much more complete picture of our state’s children. And they can be easily (and efficiently) updated for each new cohort of children born.

In addition, the index’s reliance on administrative birth records allows for validation through data linkage. Specifically, linking birth records to both child protection system and death records revealed a strong, graded relation with the predicted probability of child protection involvement and death before age 5. In other words, the more Strong Start assets a child was born with, the less likely they were to become involved with the child protection system or to die in early childhood. For more information, please refer to the California Strong Start Index Documentation.

Child-specific scores are geocoded by the mother’s residential address, and then aggregated by census tract. Means for all census tracts in California are placed along a continuum, and then grouped into quintiles (e.g., 20% groupings), each representing where that census tract’s mean score falls relative to all other census tracts in California. For example, bright green (80-100%) indicates that the average number of Strong Start assets for births in that census tract is in the top 20% for census tracts in California. Or, put another way, the average for the bright green tracts is greater than that of at least 80% of California’s tracts.

Per California’s Health and Human Services Agency (CHHS) Data De-identification Guidelines, data (and coloring) are suppressed for census tracts (and one county) with fewer than 11 births.

This index standardizes and summarizes the conditions into which children are born. Comprising twelve indicators that are universally measured, the California Strong Start Index can be used to better, more holistically characterize children across (and within) California communities, providing a tool that can help First 5s and policy makers target resources where they are needed most.

The Strong Start Index allows us to characterize the number of assets children have at birth, including how California communities have varying distributions of children at different asset levels. In addition, it facilitates the identification of communities in which children have fewer assets at birth and where additional services and supports may be important to promote equity, and characterizes how asset levels of children in different communities have changed over time, highlighting where disparities persist.

It also can act as a standardized and cost-effective anchor for community needs assessments; guide a more strategic stewardship of public dollars, with increased accountability; and promote the adoption of a common language across communities, commissions, and other stakeholder groups for conceptualizing and discussing early childhood investments.

It is our sincere hope that these data will be used to better characterize young children and families, streamline processes for stakeholders, and, ultimately, change the conversation around investments for children and families. As such, we welcome comments, questions, and suggestions as we iterate and improve the Strong Start Index.

For a printable copy of these FAQs,  click here.