10 exam-style questions with answers and explanations, straight from our 1,030-question bank. Tap an answer to check yourself. When you're ready, take the scored version in the free practice test.
These 10 free NDD questions are organized by exam domain, so you can see how each part of the Certification in Neurodevelopmental Disabilities blueprint is tested. Reveal the answer and explanation under each question.
Domain 1: Normal development (4-6%)
Question 1
A 16-year-old has missed first-period classes for six months. He gets into bed at 10:30 p.m. but usually cannot fall asleep until about 2 a.m., even without evening caffeine or electronic devices. During a two-week school break, his sleep diary shows consistent sleep from approximately 2 a.m. to 10:30 a.m.; he awakens refreshed and has no daytime sleepiness. There is no snoring, witnessed apnea, or uncomfortable urge to move his legs. Which sleep disorder best explains the contrast between school days and unrestricted days?
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Correct answer: B - Delayed sleep-wake phase disorder
Domain 2: Genetic and developmental disorders (8-10%)
Question 2
An eight-year-old boy has intellectual disability and autistic features. Chromosomal microarray and trio exome sequencing were nondiagnostic. A three-generation history reveals that his mother developed primary ovarian insufficiency at 32 and his maternal grandfather developed intention tremor and progressive gait ataxia in his sixties. Which molecular investigation is most likely to resolve the family's findings?
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Correct answer: A - FMR1 CGG-repeat analysis with methylation assessment
Question 3
A 24-year-old woman with phenylalanine hydroxylase deficiency is planning pregnancy. She stopped dietary treatment several years ago and has repeated phenylalanine concentrations near 840 micromol/L. Her partner's comprehensive PAH carrier testing is negative, making an affected fetus unlikely. She asks whether that result means metabolic treatment can wait. Which preconception recommendation is warranted?
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Correct answer: B - Reestablish metabolic control before conception, aiming for phenylalanine of 120-360 micromol/L
Domain 3: Cognitive disorders (8-10%)
Question 4
A family is alarmed that their child's Vineland-3 Adaptive Behavior Composite fell from 76 at age five to 67 at age seven. Both assessments used the same interview form and caregiver, and administration was valid. Item-level review and school observations document newly acquired communication and daily-living skills, with no loss of previously mastered abilities. Which interpretation belongs in the follow-up assessment?
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Correct answer: C - Skills have increased, but development has not kept pace with age-based expectations
Domain 4: Learning disabilities (7-9%)
Question 5
An eight-year-old understands age-appropriate stories when they are read aloud but guesses unfamiliar printed words from their first letter and surrounding pictures. She has marked difficulty blending individual speech sounds and decoding unfamiliar letter sequences. Hearing, corrected vision, and attendance are satisfactory. Eight months of small-group support emphasizing picture clues and memorizing word lists has produced little improvement. What instructional change most directly addresses the demonstrated reading deficit?
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Correct answer: A - Systematic phonemic-awareness and letter-sound instruction with guided decoding and spelling
Domain 5: Communication disorders (6-8%)
Question 6
A speech-language pathologist asks a four-year-old to repeat the same familiar word several times. The child produces different consonant and vowel errors on successive attempts, separates syllables with unusual pauses, and places stress on the wrong syllable. Errors increase with longer words. Hearing, oral strength, tone, and reflexes are normal, and receptive language is age appropriate. The findings most strongly implicate which part of speech production?
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Correct answer: D - Planning and programming the sequence of articulatory movements
Domain 6: Autism spectrum disorder (8-10%)
Question 7
At 14, a girl is evaluated because friendships have become increasingly difficult. Across home and school, she struggles with reciprocal conversation, rarely coordinates gestures with speech, and misses cues about relationships despite average cognitive and structural language skills. Preschool records describe hours spent lining up objects and intense distress when familiar routes changed. Those behaviors are now much less apparent. She wants friends and does not describe fear of embarrassment as the reason interactions break down. Which diagnosis best integrates her current difficulties and early history?
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Correct answer: C - Autism spectrum disorder
Domain 7: Attention-deficit and disruptive behavior disorders (7-9%)
Question 8
Methylphenidate has substantially improved a ten-year-old's classroom participation, work completion, and impulsive behavior. His mother now asks whether treatment should stop because she has noticed blinking and throat-clearing. Review of earlier videos confirms both behaviors before medication began. They wax and wane, do not consistently change with dosing, and cause the child no distress, pain, or interference. Appetite, growth, sleep, pulse, and blood pressure remain satisfactory. How should the medication plan be handled?
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Correct answer: D - Continue methylphenidate and monitor the tics and their functional impact
Domain 8: Motor disabilities (8-10%)
Question 9
During hip surveillance for an eight-year-old with bilateral spastic cerebral palsy, a properly positioned anteroposterior pelvic radiograph shows an ossified femoral head 32 mm wide; 13 mm lies lateral to Perkin's line. Hip abduction is 38 degrees, and the child reports no pain. What are the approximate migration percentage and the appropriate disposition?
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Correct answer: B - 41%; refer to pediatric orthopedics despite the absence of hip pain
Domain 11: Neurodevelopmental disorders associated with major medical conditions (5-7%)
Question 10
Routine screening in a nine-year-old with HbSS shows nonimaging transcranial Doppler time-averaged mean maximum velocities of 212 and 218 cm/s in the middle cerebral artery on two separate visits while well. Neurologic examination is normal. Brain MRI shows no infarct, and MRA shows no large-vessel stenosis. The child has never received regular transfusions; the center can reliably provide them. Which stroke-prevention strategy should now be offered?
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Correct answer: C - Regular red-cell transfusions for primary prevention of stroke