Rudolph's Pediatrics, 22nd Ed.

CHAPTER 82. Standardized Developmental Screening and Assessment Instruments

Martin T. Stein

Each pediatric encounter is an opportunity to monitor a child’s development at a single point in time. Making focused observations about developmental progress and behavioral patterns should be an integral part of each pediatric encounter—in the office or clinic, during acute visits and those for chronic conditions, in the emergency department or an inpatient setting, and during telephone calls. Careful observations and active inquiries about developmental milestones and behaviors provides clinicians with clinical insights into the child and the family.1 Children can be our guides.

Children will do their own developmental assessment if you just give them a chance. Children always practice the leading edge of their developmental competency, work at an emerging or newly acquired skill, and delight in a toy or activity that is just a little new and challenging. The clinician should set the agenda, set the stage, and then let the drama begin. This process depends on the clinician knowing what to look for, what to ask, and what simple maneuvers can be done quickly with a child and family.2

DEVELOPMENTAL AND BEHAVIORAL SURVEILLANCE

The ongoing process of developmental and behavioral monitoring is the core of developmental surveillance. It is a flexible and longitudinal process that occurs over time in the context of continuity of care in a primary care pediatric setting. Developmental surveillance simultaneously supports healthy development, provides parent education, and identifies children at risk for developmental delays and behavioral conditions. The major components of surveillance are eliciting parent concerns with direct questions, maintaining a developmental history, making informed observations of the child (and child-parent interactions), identifying risk and protective factors, and documenting findings in the medical record.3

One of the most effective ways to feel confident that developmental and behavioral surveillance is a part of each encounter is to ask the parent directly, “Do you have any concerns about your child’s development or behavior?” This open-ended question with an emphasis on the word concern has been shown in many different languages to yield accurate information. The success of this strategy is dependent on allowing the parent enough time to respond without quickly going off to the next question. It requires sufficient time for the parent to tell her story. A parent’s concern often provides the elements of an initial impression that may lead to other questions or a formal screening test.4

Surveillance requires attention to interpersonal process of a clinical interview in order to obtain accurate information. Characteristics of an effective interview include the enhancement of trust, empathy, limiting anxieties that restrict information exchange, and active participation of the parent as discussed in Chapters 3 and 4.

Surveillance can be enhanced by the use of “developmental themes” as a way to focus well-child visits. With the recognition that children progress along several dimensions at any one time, there is usually a specific theme that captures major changes at each age. The use of a developmental or behavioral theme for each preventive visit encourages the clinician to organize questions, observations, the examination, and anticipatory guidance around a particular theme. In this way, surveillance for age-expected milestones can be monitored in a broader context. Clinical probes supported by a theme allow quick access to understanding a child and family. Utilizing themes enhances clinical encounters by encouraging the discovery of connections between individual milestones and events in a child’s life. Some examples of developmentally focused surveillance themes during well-child visits are2:

6 months: Reaching out

8–9 months: Exploring and clinging

15–18 months: Declaring independence and pushing the limits

2 years: Language leaps

3 years: The emergence of magic

4 years: A clearer sense of self

DEVELOPMENTAL SCREENING

Screening for delays in child development is accomplished by the use of a standardized questionnaire usually completed by a parent. A few developmental screening instruments incorporate testing a child for specific tasks. Most developmental screening tests are based on the Gesell neuromaturational theory of development.5 This formulation of child development is predicated on milestones of motor, language, social, and cognitive skills that emerge at predictable times and reflect an orderly sequence of brain maturation.

Historically, pediatricians have relied on surveillance as a method of monitoring development and behavior. The American Academy of Pediatrics currently recommends that in addition to surveillance at each well-child visit, a standardized developmental screening tool should be administered at 3 well-child visits during the first 3 years of life: at 9, 18, and 30 months.1,6 Standardization refers to the achievement of adequate psychometrics that include sensitivity, specificity, validity, predictive value, and reproducibility. The 3 periods of early development were chosen because they are times when development achievements in particular domains may be assessed with accuracy: at 9 months, gross and fine motor skills, stranger response, and early object permanence; at 18 months, language and social reciprocity milestones that suggest autistic spectrum disorder (see Chapter 92); 30 months, expressive and receptive language (especially among the 15–20% of “late talking” toddlers, many of whom will be normal at 30 months (see Chapter 86).

Developmental screening instruments are organized into 4 categories: general development, language/cognitive development, motor development, and autism screening. Descriptions of available screening tests in each category are presented in Table 82-1. Important differences are in age range, administration time, psychometric qualities, and the number and type of milestones ascertained. Questionnaires vary in content and the way they formulate questions directed to parents. It is recommended that primary care pediatricians develop expertise in 1 test in each category. To insure the regular use of screening tests during designated well-child visits, the office or clinic staff must have a system by which the administration, scoring, and follow-up plans are assured.

Table 82-1. Developmental Screening

A unique form of general developmental screening is the Parents’ Evaluation of Developmental Status (PEDS). The parent is asked about concerns in 8 developmental, behavioral, and learning domains. The PEDS is based on research that found the word concern to be an accurate way to learn about a parent’s perception of his or her child’s development and behavior.4

There are advantages and potential pitfalls in using screening tests in primary care pediatrics (eTable 82.1 ). The potential pitfalls of screening may be limited by their use as an adjunct to the clinical interview. When a screening tool is completed before the interview (eg, at home on a dedicated Web site or in the office during the waiting time), parent responses may be used to focus a clinical interview in areas of importance to the parent. Standardized screening tests often trigger questions, raise issues, and prevent omissions in data collection. Optimal well-child care includes both screening and face-to-face discussions about development and behavior. To maximize the quality of the screening process, the Healthy Steps programs includes a person on the office staff with child development training who has responsibility for systematic screening for developmental and behavior during well-child visits.7

Development and behavior are inseparable. They are both a result of brain maturation mediated by genetic endowment and environmental experience. Observation of behavior is a component of all developmental surveillance, screening, and assessment. In young children, the Ages and Stages Questionnaires: Social-Emotional screening instrument is useful in primary care settings. For children and youth 4 to 16 years of age, the Pediatric Symptom Checklist8 is an opportunity to screen for internalizing problems (eg, anxiety and depression) and externalizing problems (eg, attention deficit hyperactivity disorder, oppositional behaviors, and conduct disorder). Asking a child at each well-child visit beginning at age 5 years to “draw a picture of your family doing something” often yields useful information about fine motor skills, visual-perceptual skills, self-image, and the child’s perception of his or her place in the family (see Fig. 82-1).2

When a screening test is positive (ie, suggests a problem in 1 or more domains of development or behavior), the next step is a comprehensive and focused interview followed by a neurodevelopment examination by the primary care clinician. For mild to moderate problems, pediatricians are often in a position to provide education and counseling or initiate a medical evaluation. In other cases, a referral to a developmental-behavioral pediatrician, child psychologist, child psychiatrist, or other mental health clinician is appropriate. Pediatric clinicians have a responsibility to be aware of available resources in their community in order to refer a child for a comprehensive developmental and/or behavioral assessment.

Figure 82-1. A: A 53/4-year-old girl drew diminutive self holding hands with her father, while her 3-year-old sister (below) is magnified next to her mother. The family drawing was completed during the waiting period at a well-child visit. The mother did not express any concerns until she viewed the drawing and said, “I meant to bring up the constant fussing between the two girls; they are always at each other.” The drawing encouraged a discussion with the mother about normal sibling rivalry. B: An 8-year-old girl with a brief history of functional headaches and recurrent abdominal pain drew this picture of her family. Shortly before the onset of symptoms, her grandmother died, and she attended the funeral with her family. The drawing provided the pediatrician with an opportunity to talk to the parents about the effect of a significant loss on a school-aged child. With the drawing, the child was also engaged in a dialog to talk about the death of her grandmother. Somatic symptoms resolved in a few days.

DEVELOPMENTAL ASSESSMENT

A developmental assessment may include an evaluation of cognition, communication, motor skills, daily living skills, and social-behavioral patterns. They are “standardized” when they meet psychometric measures including reliability (stability, test-retest reliability, and interobserver reliability) and validation (measures what it purports to measure and is validated against another previously validated test).9

A developmental assessment may establish a specific diagnosis to facilitate an intervention or determine the severity and prognosis of a condition. An assessment may measure strengths and weaknesses in intelligence, developmental, achievement, or behavior. These evaluations often assist in the determination of eligibility and/or reimbursement for services as well as in monitoring and evaluating a treatment plan.

Selection and administration of standardized tests is typically performed by a professional with training in psychometric testing. While screening tests are an integral part of pediatric primary care practice, developmental assessment is usually the responsibility of a clinical child psychologist, a developmental-behavioral pediatrician, a neuropsychologist, or a master-level person who is trained in testing. Observing the child’s behavior, play skills, and social use of language is an important aspect of the evaluation.

Standardized tests may not always measure what they claim to measure. Motivation and cooperation may impact performance. Some children with attention problems may not perform well with timed tests. For example, a child with an attention deficit may receive a low score on a language test because of distraction and a problem with focusing during the test. Situational anxiety, an unfamiliar setting, and rapport with the examiner may also influence test results. For some children, multiple choice tests do not satisfactory reflect their abilities.

Tests are developed with a normative sample of children. They are typically renormed every 15 to 20 years because many measures of development (eg, intelligence tests) increase over time (the “Flynn effect”). A standardized assessment measures a developmental or behavioral domain at one point in time; predictions of future development should be made with caution, especially before age 5 years.

A single measure does not evaluate all areas of development. Tests for toddlers and pre-school children typically focus on motor, language and social development. Others include measures of cognitive skills that yield a “mental age” score or intelligence quotient (IQ). Developmental assessment metrics for school-aged children and adolescents emphasize more complex cognitive skills; they measure either aptitude (general intelligence or IQ) or achievement. Intelligence tests measure language-based cognition, nonlanguage-based cognition (eg, perceptual reasoning and working memory), and processing speed. However, they may not measure other important areas of a child’s strengths, such as musical intelligence, artistic intelligence, and social intelligence, that reflect a growing appreciation of multiple intellectual strengths and weakness in each individual.10 The recognition of different areas of intelligence has guided a clearer understanding of individual differences in learning (see Chapter 85).

It is useful to distinguish between developmental tests and intelligence tests. An intelligence test assesses different aspects of cognitive abilities, such as reasoning, knowledge, quantitative analysis, visuospatial processing, and working memory. Developmental assessments measure specific developmental achievements and delays in areas of motor and social skills in comparison to same-aged peers. A selected group of the tests provides insights into what is measured, how it is measured, and the way the results are expressed.11

BAYLEY SCALES OF INFANT AND TODDLER DEVELOPMENT, THIRD EDITION (BSID-III)

The gold standard for assessing early child development, the Bayley Scales of Infant and Toddler Development is used to identify children 1 month to 42 months old with developmental delays, to initiate early intervention services, and to following a child’s progress. Scores are generated to reflect cognition, expressive and receptive language, fine and gross motor skills, and socioemotional and adaptive behaviors.

MULLEN SCALES OF EARLY LEARNING

The Mullen Scales of Early Learning provide an estimate of overall intelligence in young children (2–5 years of age). It differentiates receptive and expressive problems in visual and auditory learning. The Mullen also includes a visuomotor and gross motor score.

WECHSLER INTELLIGENT SCALE FOR CHILDREN (WISC-IV) AND WECHSLER PRESCHOOL AND PRIMARY SCALE OF INTELLIGENCE, THIRD EDITION (WPPSI-III)

The Wechsler tests of intelligence assess “fluid reasoning” (manipulating abstractions, rules, generalizations, and logical relationships) and processing speed (the time it takes to complete a mental task). The WISC-IV (applicable from 6 years to 16 11/12 years) includes 4 domains of cognitive function: verbal comprehension, perceptual reasoning, working memory and processing speed. A measure of general intelligence (full-scale IQ) is then calculated. The Wechsler scales are used for the diagnosis of mental retardation and provide categories of borderline, mild, moderate, and severe cognitive deficiency. An intelligence score on the Wechsler in the range of a cognitive disability is usually accompanied by the Vineland Adaptive Behavior Scale, a measurement of personal and social skills needed for daily living.

PEABODY PICTURE VOCABULARY TEST

The Peabody Picture Vocabulary Test measures listening skills and understanding of single words beginning at 2 1/2 years of age. By using picture recognition through pointing, a child’s cognitive abilities can be measured in the absence of speech or the ability to read or write. Another measure of intelligence available for children without spoken language is the Leiter International Performance Scale, a nonverbal test of cognitive abilities.

Intelligence tests can be seen as a measurement of a child’s mental processing abilities. An IQ is calculated by an assessment of mental age (based on test performance) divided by chronological age and multiplied by 100. How a child has used that intelligence is measured by an achievement test. Measures of achievement include the Woodcock-Johnson Test of Achievement, Wechsler Individual Achievement Test, Wide Range Achievement Test-3, and Kaufman Test of Educational Achievement-II. These tests generate a score of reading, writing, and arithmetic achievement relative to age or grade level normative data. The Gray Oral Reading Test is an achievement test for reading fluency and comprehension. It is brief, scored by grade level, and useful for primary care pediatrics for clinicians who desire to use an objective test for reading achievement.

Developmental surveillance, office-based developmental screening, and the clinical interview are fundamental tools of primary care pediatricians. Knowledge about standardized assessments of development, intelligence, and behavior enhances the ability of pediatricians to understand learning differences and to direct children to appropriate services. This knowledge also provides clinicians with data that is often useful when communicating with parents, teachers, counselors, tutors, and therapists.