The writers of the ASQ drew on several standardized developmental tests for item statements as well as literature that outlined early developmental milestones. They selected skills that could be observed or elicited easily by parents at home in the course of daily activities.
The system has 19 questionnaires designed to be administered at ages 4 months through 5 years, corresponding to common well-child visits. Five developmental areas are covered in each questionnaire—communication, gross motor, fine motor, problem solving, and personal-social. Five items query skills in each area. An overall section has 5 questions that cover general parental concerns.
Normative data were gathered from 2008 children drawn from an ethnically and socioeconomically heterogeneous population, with 81% of children judged “at-risk.”28 The items were picked to represent the developmental quotient (DQ) of 75 to 100. Validity data were gathered from the analysis of 247 children, a subset of the population used in gathering normative data.
The ASQ has a specificity ranging from 81% (16 months) to 92% (36 months), and 86% overall. There was trend toward higher specificity when screening older children. Sensitivity was lower, averaging 72%.29 Age-appropriate tests of individual cognition were used as the gold standard, including the Bayley Scales of Infant Development, Stanford-Binet Intelligence Test (4th ed), and the McCarthy Scales of Children’s Abilities.
The instrument maintains its validity when screening high-risk children: when specifically used to evaluate infants born prematurely, the ASQ had 90% sensitivity, 77% specificity.30 In this study formal assessment was performed with the Griffith Mental development Scales, Bayley Development Intelligence Scale.
Reliable tests requiring direct elicitation and observation of children
Brigance screens
The Brigance screens are not well known to physicians but are commonly used in Head Start and educational settings.31 They include 9 separate forms, each covering a 12-month age range. The Brigance requires about 15 minutes to administer and score. The screens address speech-language, motor skills, readiness, and general knowledge at younger ages, and also reading and math at older ages.
The Brigance screens were standardized using 1156 children; validity data were gathered through examining 408 children. Both groups were drawn from populations of diverse geographical and socioeconomic status, producing demographics similar to the US Census for the year 2000.
Validity data estimated the sensitivity and specificity for detecting children with delays at 82% and 75%, with a range of 72% to 100% across different years. Validity was determined through comparison with a battery of age-appropriate developmental assessment tools such as the Bayley Scales of Infant Development–II (BSID-II), Slossen Intelligence Test, and the Woodcock-Johnson Psycho-Educational Battery—Revised: Test of Achievement–II.32 A study examining the extension of the Brigance screens to children ages 0 to 2 years found the screen to maintain its sensitivity (76% to 77%) and specificity (85% to 86%).33 An additional feature of the Brigance is its ability to detect gifted and academically talented children with a sensitivity and specificity of 69% and 79%, respectively.32
The Brigance II was published in early 2006; it has a sensitivity of 70% and specificity of 82% for the detection of developmental and academic problems.34
Battelle Developmental Inventory Screening Test
The Battelle Developmental Inventory Screening Test (BDIST) can be used to screen children from age 12 to 96 months, using a combination of direct assessment, observation, and parental interview. Normative data were gathered from a geographically and socioeconomically diverse sample of 800 children.35
Studies have shown the test to possess a sensitivity of 75% and specificity of 73%.36 Validity data were gathered from 105 subjects, most of whose parents’ incomes were below poverty guidelines. A battery of tests was used as a gold standard including the Bayley Scales of Infant Development–II, Kaufman Assessment Battery for Children or the Stanford-Binet Intelligence Scale. The BDIST requires 4 to 6 hours to learn and 10 to 30 minutes to administer, and may be impractical for routine screening in primary care. The receptive language subtest may be administered in lieu of the full screen and takes just a few minutes to administer; however, that diminishes specificity to 66% while maintaining sensitivity at 80%.36
Bayley Infant Neurodevelopmental Screener
The Bayley Infant Neurodevelopmental Screener (BINS) is a recently developed test designed for screening high-risk infants aged 3 to 24 months. The test was standardized on a nonclinical sample of 600 children representative of the US Census data for 1988.37 It uses 10 to 13 directly elicited items per 3- to 6-month range to assess neurodevelopmental skills and developmental accomplishments. Data published in the technical manual found the BINS to have a sensitivity and specificity of 75% and 86%, respectively, across all ages.37