Decoding Diagnostic Tests

Understanding Common Diagnostic Tests for Children

If you or your child’s doctor have noticed signs of developmental delays or other special needs, it can feel overwhelming to figure out the next step.

Developmental delays are often a natural part of your child’s unique growth and don’t necessarily indicate a serious issue. However, getting additional assessments can ensure that your child has access to early intervention and any support they may need.

Navigating the process of seeking diagnostic tests can feel daunting, like wading through a sea of medical jargon and acronyms.

To make the process a little easier, we’ve put together a guide to some of the most common diagnostic tests — who they’re for, what they assess, and how they’re used. These assessments should always be administered by qualified professionals, like psychologists, school psychologists, speech therapists, and other specialists.

Developmental Delays: Common Screening Tools

1. Ages and Stages Questionnaires (ASQ)

• Age Range: 1 month to 5½ years
• Purpose: Screens for developmental delays in key areas such as:
  • Communication
  • Gross and fine motor skills
  • Problem-solving
  • Social skills
• Method: Parent-completed questionnaire.

2. Bayley Scales of Infant and Toddler Development (Bayley-III)

• Age Range: 1 to 3½ years
• Purpose: Comprehensive developmental evaluation covering:
  • Cognitive abilities
  • Language skills
  • Motor function
  • Social-emotional development
  • Adaptive behavior

Autism Spectrum Disorder (ASD) Diagnostic Tools

3. Autism Diagnostic Observation Schedule (ADOS-2)

• Age Range: Varies by module
• Purpose: Gold standard for diagnosing autism.
• Method: Structured, play-based observation evaluating behaviors linked to autism.

4. Childhood Autism Rating Scale (CARS)

• Age Range: Children and adolescents
• Purpose: Assesses autism symptoms and severity.
• Method: 15-point rating scale covering:
  • Verbal and non-verbal communication
  • Social interaction
  • Response to sensory input

Intellectual Disabilities: Cognitive Assessment Tools

5. Wechsler Preschool and Primary Scale of Intelligence (WPPSI-IV)

• Age Range: 2½ to 7 years
• Purpose: Measures:
  • Verbal comprehension
  • Visual-spatial skills
  • Fluid reasoning
  • Working memory
  • Processing speed
• Outcome: IQ score to identify intellectual disabilities or giftedness.

6. Stanford-Binet Intelligence Scales (SB5)

• Age Range: 2 to 85+ years
• Purpose: Evaluates five key cognitive areas:
  • Fluid reasoning
  • Knowledge
  • Quantitative reasoning
  • Visual-spatial processing
  • Working memory

Speech and Language Disorders: Assessment Tools

7. Clinical Evaluation of Language Fundamentals (CELF-5)

• Age Range: 5 to 21 years
• Purpose: Diagnoses language disorders through evaluation of:
  • Syntax
  • Semantics
  • Pragmatics
  • Language memory

8. Preschool Language Scales (PLS-5)

• Age Range: Birth to 7 years
• Purpose: Assesses:
  • Auditory comprehension
  • Expressive communication
• Outcome: Identifies early language delays and areas for support.

Motor Skill Issues: Evaluation Tools

9. Peabody Developmental Motor Scales (PDMS-2)

• Age Range: Birth to 5 years
• Purpose: Detects motor skill delays through:
  • Fine motor skill assessment (grasping, drawing)
  • Gross motor skill assessment (walking, jumping)

10. Bruininks-Oseretsky Test of Motor Proficiency (BOT-2)

• Age Range: 4 to 21 years
• Purpose: Measures:
  • Balance
  • Coordination
  • Agility
  • Strength
• Use: Ideal for designing physical therapy programs.

Adaptive Behavior Concerns: Functional Living Skills Tests

11. Vineland Adaptive Behavior Scales (Vineland-3)

• Age Range: Birth through adulthood
• Purpose: Assesses:
  • Communication
  • Daily living skills
  • Socialization
  • Motor skills

12. Adaptive Behavior Assessment System (ABAS-3)

• Age Range: All ages
• Purpose: Measures adaptive behaviors for daily life:
  • Conceptual
  • Social
  • Practical skills
• Use: Supports IEP development and treatment planning.

Learning Disabilities: Academic Skill Assessments

13. Wechsler Individual Achievement Test (WIAT-III)

• Age Range: 4 to 50 years
• Purpose: Identifies learning disabilities in:
  • Reading
  • Math
  • Written and oral language

14. Woodcock-Johnson Tests of Achievement (WJ-IV)

• Age Range: 2 to 90+ years
• Purpose: Evaluates academic skills and guides intervention strategies.

ADHD: Behavioral Rating Scales

15. Conners Comprehensive Behavior Rating Scales (CBRS)

• Age Range: 6 to 18 years
• Purpose: Assesses:
  • Inattention
  • Hyperactivity
  • Impulsivity
• Method: Ratings by parents, teachers, and the child.

16. Vanderbilt ADHD Diagnostic Rating Scale

• Age Range: 6 to 12 years
• Purpose: Helps diagnose ADHD symptoms across home and school settings through:
  • Parent and teacher evaluations