3.3 Pediatric Developmental Assessment

Quick Answer: Official ANCC age bands here are infant, preschool, and school-age. Plot WHO growth charts from 0–2 years and CDC charts from age 2; use weight-for-length until 2 and BMI after. Screen all developmental domains at every well visit; treat no babble at 9 months, no words at 15–18 months, no two-word phrases at 24 months, or any loss of skills as red flags. Add M-CHAT-R/F at 18 and 24 months. ADHD needs home and school ratings. Refer Early Intervention for red flags; do not watch-and-wait regression.

Family nurse practitioners assess children across three official pediatric bands: infant, preschool, and school-age. The exam rewards a structured approach — growth, development, targeted physical findings, immunization status, and safety — not a vague impression that the child 'looks well.'

Growth: which chart and which index

Use WHO growth charts from birth to 2 years. They describe how children should grow under optimal, predominantly breastfed conditions. Switch to CDC charts at age 2, when BMI-for-age becomes the U.S. standard and the WHO child-growth standard ends.

Until the second birthday, the adiposity index is weight-for-length, not BMI. At age 2 and older, plot BMI-for-age. Continue head circumference at every visit until at least age 2 and commonly through age 3; after that, measure sooner if you suspect abnormal growth of the skull or brain.

Correct for prematurity when you plot: commonly until 24 months for weight, about 40 months for length/height, and 18 months for head circumference. One off-curve point is a reason to remeasure, not a diagnosis.

Failure to thrive is a pattern: weight below the 3rd to 5th percentile, weight-for-length below the WHO 2nd percentile, or a downward cross of two or more major percentile lines. Assessment starts with observed feeding, caloric intake, vomiting or diarrhea, social risk, and a complete exam — not a reflex admission or a lecture about 'picky eating.' Inadequate intake, malabsorption, and increased metabolic demand are the three mechanistic buckets.

Constitutional growth delay looks different: normal size at birth, a downward bend in the first 2–3 years, then a curve that runs parallel to the percentile lines, a delayed bone age, and a family history of late puberty. Familial short stature has short parents, normal growth velocity, and a bone age equal to chronologic age. Do not label either pattern failure to thrive, and do not dismiss true failure to thrive as 'just like dad' without velocity data.

Developmental domains and how you actually screen

Every well visit reviews five domains: gross motor, fine motor, language (receptive and expressive), social-emotional, and cognitive/problem-solving. Surveillance is the conversation and observation you do every time: parental concern, milestone review, how the child plays in the room, and risk factors (prematurity, hearing loss, lead, early adversity). Structured screening (ASQ-3, ASQ:SE, M-CHAT-R/F, and later Vanderbilt) is added at recommended ages or whenever surveillance is concerning. Surveillance without a validated tool, or a tool without watching the child, is an incomplete assessment.

Red flags by age — refer, do not 'wait until the next well visit'

Language anchors worth memorizing: about one word plus specific mama/dada near 12 months, a rapidly growing single-word vocabulary by 18 months, and two-word combinations with roughly 50 words by 24 months. Hearing must be in the differential of every language delay. Do not tell a family that 'boys talk late' and close the chart.

Autism surveillance and M-CHAT-R/F

Autism surveillance is continuous: poor eye contact, limited response to name, no pointing to share interest, repetitive behaviors, and regression. Add a structured screen with M-CHAT-R/F at 18 and 24 months (validated 16–30 months) and whenever concern appears. High-risk scores refer immediately for autism-specific evaluation, audiology, and Early Intervention. Medium-risk scores get the follow-up interview; if they remain positive, refer. Do not wait until the third birthday 'to be sure.' A diagnosis is not required to start Early Intervention.

School-age ADHD is not a 10-minute impression

ADHD assessment requires symptoms that are developmentally excessive, present in more than one setting, and impairing function at home and school. Collect parent and teacher Vanderbilt (or equivalent) ratings, a sleep and snoring history, vision and hearing, learning concerns, mood and anxiety, and recent stressors. An 8-year-old who is squirmy on a 12-minute sick visit while the parent requests a stimulant is not an adequate data set. Treat comorbidities and mimics — sleep apnea, hearing loss, lead, learning disability, anxiety — as part of the assessment, not as afterthoughts after a prescription.

School function itself is data: grades, IEP or 504, suspensions, attendance, and bullying. A child with normal motor milestones who cannot decode in third grade has a functional problem even if no DSM label has been applied yet.

Tanner staging — approach without a graphic lecture

Use sexual maturity ratings 1 through 5 for breast, genital, and pubic-hair development. You need the sequence and the timing, not a pornographic description. In girls, breast budding (thelarche) is usually the first sign; in boys, testicular enlargement is. Concerning precocious puberty is pubertal signs before age 8 in girls or 9 in boys. Concerning delay is no breast development by 13 or no testicular enlargement by 14. Document the stage, growth velocity, and whether the sequence is congruent. Isolated pubic hair with no breast or testicular change is often premature adrenarche and is assessed differently from true central puberty.

Targeted physical findings the exam expects

HEENT. Red reflex in both eyes in infancy (absent or white reflex is urgent), cover-uncover for strabismus once the child will cooperate, dentition and caries, and tympanic membranes when infection or hearing delay is in play. Persistent mouth-breathing and snoring belong in the functional history because they change sleep, behavior, and growth.

Heart — innocent versus pathologic. A Still murmur is the classic innocent murmur: grade 1–2, musical or vibratory, lower left sternal border, louder when supine, softer when sitting or standing, with a normal S2 and normal growth. A pulmonary-flow murmur is soft at the upper left sternal border. A venous hum is continuous, infraclavicular, and disappears when the child lies down or when the jugular vein is gently compressed. Pathologic clues: holosystolic or diastolic timing, grade 3 or louder, harsh quality, a thrill, radiation to the back or neck, a fixed split S2, symptoms, poor growth, or blood-pressure discrepancy between arms and legs (think coarctation). Those findings are a cardiology referral, not a 'recheck next year.'

Hips. In early infancy use Ortolani (reduces a dislocated hip — a clunk in) and Barlow (dislocates a dislocatable hip). After about 3 months those maneuvers are less useful; limited abduction, Galeazzi (unequal knee height), asymmetric thigh creases, and a limp when walking take over. A late-presenting limp with limited abduction is developmental dysplasia until proven otherwise.

Testes. Both testes should be in the scrotum in the term newborn. Distinguish retractile from truly undescended. If a testis is not stably descended by 6 months, refer to pediatric urology — do not keep 'checking next visit' through the second year.

Spine. Adams forward-bend test, shoulder or scapular height, and waist creases. You do not calculate a Cobb angle in primary care; you decide whether the exam warrants scoliometer measurement and imaging or orthopedic referral.

Immunization status is assessment data

An incomplete record is a risk finding, not merely a nursing task. The assessment question is which doses are missing, whether contraindications or precautions exist, and whether a household member is immunocompromised (live-vaccine implications). Catch-up scheduling is planning; recognizing that a 4-year-old has no documented MMR before kindergarten entry is assessment.

Anticipatory-safety questions — ask them, do not only hand a pamphlet

These questions are part of the history of present environment. A toddler with a burn and an inconsistent story, or an infant not placed supine, changes your risk assessment for injury and possible maltreatment.

When to refer Early Intervention versus watchful waiting

Refer now (do not watch): loss of any skill; failed M-CHAT-R after follow-up; no words by 15–18 months or no two-word phrases by 24 months; asymmetric motor findings; progressive microcephaly or macrocephaly; an established qualifying condition (for example significant prematurity or a genetic syndrome). IDEA Part C Early Intervention typically covers birth to the third birthday; you do not need a specialist's diagnostic label to refer.

Short-interval watchful waiting is acceptable only for an isolated, borderline delay with a normal exam, normal hearing risk, a reassuring social environment, and a specific recheck date — not an open-ended 'let's see.' If the family is worried, treat that concern as a positive screen until you have disproved it.

Vignette

An 18-month-old is in for a well visit. Birth was at term. Weight has crossed from the 50th to the 10th percentile since the 12-month visit; length remains near the 40th. He has three single words, does not point to share interest, and no longer waves, which he did at 12 months. He is still rear-facing in the car. The father mentions an unlocked hunting rifle in a closet. The murmur you hear is grade 2, musical, and softer when you sit the child up; S2 is normal and growth of length is preserved.

Assessment problems that change the plan: downward weight crossing (failure-to-thrive workup, not 'he is busy'), language delay plus loss of waving plus no pointing (same-day M-CHAT-R/F and Early Intervention/audiology referral — not 'boys talk late'), firearm access, and an innocent Still murmur that does not need cardiology if the rest of the cardiac assessment stays reassuring. Function and safety, not the murmur, drive today's work.