The Child Development Inventory (CDI): for assessing toddlers and preschoolers. (Ireton, 1992)

The CDI is for children age 15 months to six years, and for older children who are judged to be functioning in the one- to six-year range. The CDI measures the child’s present development in eight areas: social, self help, gross motor, fine motor, expressive language, language comprehension, letters, and numbers. It also includes a General Development Scale. The Inventory includes 30 items to identify parents’ concerns about their child’s health and growth, vision and hearing, development and behavior.

The CDI is used primarily for assessment, often early on to obtain additional information about children whose development is questionable, for example, when a parent or professional have some question about a child’s language development. The CDI results can help guide professional assessment of the child’s functioning. Parent’s CDI reports are then integrated with professional’s observation and test results.

This version of the CDI is the results of 30 years of research and clinical experience with the Minnesota Child Development Inventory (MCDI: Ireton and Thwing, 1972) and related inventories created for narrower age groups.

Clinical experience using the MCDI with concerned parents of children with developmental delays/disabilities has shown that most parents welcome the opportunity to be actively involved in the assessment process.

The CDI consists of a 300-item booklet and answer sheet for the parent to complete, and a Child Development Inventory Profile sheet for recording results. The CDI booklet includes 270 statements that describe the behaviors of children in the first six and one-half years of life. These items describe developmental skills of young children that are observable by parents in everyday situations. These items were found, through research, to differentiate older children from younger children.

CDI Profile
The CDI Profile pictures the child’s development in comparison to norms for children age one to six years. Problem items are listed at the bottom of the CDI Profile.

The CDI was standardized on a norm sample of 568 children age one to six years. The norm sample was obtained in South St. Paul, Minnesota. South St. Paul is a primarily white working class community. It is located in a large metropolitan area, Minneapolis/St. Paul, but is neither inner city nor suburban. It is located between St. Paul and the surrounding suburbs. It is an established community that does not have extremes of either wealth or poverty. The children in the public school system have an average IQ of 100 (mean eighth grade student performance on the Short Form Test of Academic Aptitude.)

CDI Validity
The validity of the CDI was determined in three ways: first, by examining results for norm group children at younger and older ages; second, by comparing CDI results to psychological test results; and third, by looking a CDI results for children with developmental and other problems. The CDI developmental scales correlate closely with age: median (r=.84). CDI results identified all the norm group children who were enrolled in early childhood/special education (N=26) and correlated with reading achievement for children in kindergarten as follows: General Development (.69); Letters (.56); Language Comprehension (.42); Expressive Language (.36); and Self Help (.35).

Early Childhood/Special Education Validity Study
Nineteen of the 26 early childhood/special education children (73%) had CDI Profiles that were delayed in one or more areas, compared to 11% in the norm group. 7 of the 19 CDI delayed children had generally delayed Profiles, including a General Development Scale in the delayed range CDI Profiles, five children’s parents were concerned about their speech and language; one child was described as “severely shy,” and one had juvenile rheumatoid arthritis. Among the 26 early childhood/special education children, all were identified by either having a delayed CDI Profile (19) or by parent concerns reported on the CDI (7). The CDI results for these children appear to meaningfully describe the range of these children’s problems from lesser speech and language problems to general developmental disabilities.

Child Development Inventory Manual PDF (includes validity and reliability)

Many other studies have been done with the CDI over the years, revealing extremely high validity. Here are a few examples:

Assessing children's development using parents' reports. The Child Development Inventory

The Child Development Inventory: A developmental outcome measure for followup of the high-risk infant