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ABP General Pediatrics study materials
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ABP General Pediatrics practice questions

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Question 1Growth and Development

A healthy term breastfed newborn is weighed on the fourth day of life. Which weight loss from birth weight is still within normal limits?

  1. From 16% to 20%
  2. From 21% to 25%
  3. Up to 10% Correct answer.
  4. More than 25%

Explanation

Term newborns commonly lose 5% to 10% of birth weight in the first days because of extracellular fluid loss and limited intake, and they usually regain birth weight by 10 to 14 days. A loss greater than 10% should prompt assessment of feeding, hydration, and bilirubin.

Question 2Growth and Development

At approximately what age does a healthy term infant typically double the birth weight?

  1. 5 months Correct answer.
  2. 15 months
  3. 9 months
  4. 2 months

Explanation

Birth weight usually doubles by about 4 to 5 months and triples by about 12 months. These landmarks are quick ways to confirm adequate growth between visits.

Question 3Growth and Development

What is the typical head circumference of a healthy term newborn?

  1. 40 cm
  2. 30 cm
  3. 35 cm Correct answer.
  4. 25 cm

Explanation

Head circumference at birth averages about 35 cm, with a normal range of roughly 33 to 37 cm, and exceeds chest circumference by about 2 cm.

Question 4Growth and Development

At what age does the first primary tooth usually erupt?

  1. 14 to 16 months of age
  2. 2 to 3 months of age
  3. 5 to 8 months Correct answer.
  4. 10 to 12 months of age

Explanation

Primary teeth begin to erupt at about 5 to 8 months, usually starting with the mandibular central incisors. Eruption timing varies widely, but absence of any teeth by about 13 to 15 months warrants evaluation.

Question 5Growth and Development

A social, responsive smile typically first appears at which age?

  1. At birth
  2. 7 months
  3. 4 months
  4. 6 to 8 weeks Correct answer.

Explanation

The social smile, a smile in response to a human face or voice, appears at about 6 to 8 weeks and marks the beginning of reciprocal social interaction. Its absence by 2 to 3 months warrants attention.

Question 6Growth and Development

Independent sitting without support is typically achieved by which age?

  1. 15 months
  2. 12 months
  3. 2 to 3 months of age
  4. 6 to 8 months Correct answer.

Explanation

Independent sitting without support emerges between 6 and 8 months once head and trunk control are established. By 12 months most infants are pulling to stand or cruising.

Question 7Growth and Development

A baby born at 28 weeks' gestation is assessed at 12 months of chronological age. Which adjustment should be applied when interpreting developmental milestones?

  1. Add 3 months
  2. Subtract 3 months Correct answer.
  3. Subtract 6 months
  4. No correction needed

Explanation

Preterm infants are assessed using corrected age, calculated as chronological age minus the number of weeks born before 40 weeks, until about 2 to 2.5 years. Birth at 28 weeks is 12 weeks (3 months) early, so the corrected age at 12 months chronological is 9 months.

Question 8Growth and Development

Which finding is the first clinical sign of puberty in boys?

  1. Growth spurt
  2. Testicular enlargement Correct answer.
  3. Pubic hair growth
  4. Voice deepening

Explanation

In boys the first sign of central puberty is testicular enlargement, generally to at least 4 mL or 2.5 cm in length, typically between 9.5 and 14 years. Other androgen effects follow.

Question 9Growth and Development

A 9-month-old whose length tracked the 50th percentile since birth is now at the 10th percentile, having crossed two major percentile lines over 3 months. What is the most appropriate next step?

  1. Evaluate for an underlying cause of poor growth Correct answer.
  2. Repeat the measurement in 12 months
  3. Reassure the family because the value is above the 3rd percentile
  4. Switch to a high-calorie formula without further assessment

Explanation

Falling across two or more major percentile lines is a red flag for failure to thrive and warrants evaluation of intake, underlying medical illness, and psychosocial factors, even when the current value remains above the 3rd percentile.

Question 10Growth and Development

A 10-year-old boy is at the 5th percentile for height with a bone age of 7 years, delayed puberty, and parents of average height. Which diagnosis is most consistent with these findings?

  1. Constitutional delay of growth and puberty Correct answer.
  2. Growth hormone deficiency from a pituitary tumor
  3. Turner syndrome
  4. Familial short stature

Explanation

A bone age delayed by 2 to 4 years, delayed puberty, normal growth velocity, and average parental heights fit constitutional delay of growth and puberty, a normal variant with eventual spontaneous puberty and catch-up growth.

Question 11Growth and Development

Which finding best meets the definition of failure to thrive in a 6-month-old?

  1. Weight at the 25th percentile and length at the 50th
  2. Weight-for-age below the 3rd percentile on two visits Correct answer.
  3. A single weight measurement below the 15th percentile
  4. Weight gain of 15 g per day over 2 months

Explanation

Failure to thrive is defined by weight-for-age below the 3rd percentile, a fall across two or more major percentile lines, or weight-for-length below the 10th percentile on serial measurements. Growth must be assessed over time, not from a single value.

Question 12Growth and Development

Which language milestone is expected at 24 months of age?

  1. Following only one-step commands with gestures
  2. Speaking 500 words and telling short stories
  3. Using two-word phrases and about 50 words Correct answer.
  4. Using short sentences of three or more words with grammar

Explanation

At 24 months children typically use two-word phrases and have a vocabulary of roughly 50 words, with a normal range up to about 100. A child who is not combining words by 24 months should be evaluated.

Question 13Growth and Development

At which ages does the American Academy of Pediatrics recommend universal screening for autism spectrum disorder?

  1. 9 months only
  2. 6 and 12 months
  3. 36 and 48 months
  4. 18 and 24 months Correct answer.

Explanation

Universal autism screening with a validated instrument such as the M-CHAT-R/F is recommended at the 18- and 24-month visits, in addition to developmental surveillance at every well-child visit.

Question 14Growth and Development

Which instrument is a validated, parent-completed general developmental screening questionnaire recommended at 9, 18, and 30 months?

  1. Ages and Stages Questionnaire Correct answer.
  2. M-CHAT-R/F
  3. Bayley Scales of Infant Development
  4. Vineland Adaptive Behavior Scales

Explanation

The Ages and Stages Questionnaire is a parent-completed general developmental screener recommended at the 9-, 18-, and 30-month visits. It identifies children who need further diagnostic assessment.

Question 15Growth and Development

A 20-month-old who previously said 20 words and waved goodbye has stopped speaking and no longer responds to his name. What is the most appropriate action?

  1. Reducing screen time and returning in 1 year
  2. A hearing test in 6 months
  3. Reassurance that late talking is common; recheck at 3 years
  4. Prompt audiology and developmental evaluation Correct answer.

Explanation

Loss of previously acquired language or social skills is a red flag for autism spectrum disorder or a neurodegenerative process and requires prompt audiology and developmental evaluation. Regression is never a normal variant.

Question 16Growth and Development

A 6-month-old has an absent red reflex in the left eye, and the parents report a white pupillary reflex in photographs. What does this most likely indicate?

  1. A normal finding needing no action
  2. A refractive error correctable with glasses
  3. Leukocoria warranting urgent ophthalmology referral Correct answer.
  4. Bacterial conjunctivitis

Explanation

An absent red reflex with leukocoria in an infant suggests retinoblastoma, congenital cataract, or another serious ocular disorder and requires urgent ophthalmologic evaluation. Normal red reflexes should be symmetric and present from birth.

Question 17Growth and Development

Persistence of the Moro reflex at which age is most suggestive of a central nervous system abnormality?

  1. 2 months
  2. 1 month
  3. 6 months Correct answer.
  4. 3 months

Explanation

The Moro reflex is present at birth and normally resolves by about 3 to 4 months. Persistence at 6 months suggests a central nervous system abnormality such as cerebral palsy.

Question 18Growth and Development

A 12-month-old consistently uses only the left hand for reaching and grasping. How should this be interpreted?

  1. It warrants evaluation for hemiparesis Correct answer.
  2. It suggests a primary language disorder
  3. It confirms the child is left-handed
  4. Expected, because handedness is set by 12 months

Explanation

Handedness is not established until about 18 to 24 months. A consistent one-handed preference before 18 months warrants evaluation for contralateral hemiparesis from causes such as cerebral palsy or a vascular event.

Question 19Growth and Development

Which growth pattern in a prepubertal child most strongly suggests an endocrine cause of short stature?

  1. Falling height percentiles with velocity under 4 cm per year Correct answer.
  2. Height at the 25th percentile with normal growth velocity
  3. Height at the 5th percentile with bone age equal to chronological age
  4. Adult height prediction consistent with midparental height

Explanation

Growth hormone deficiency produces declining height percentiles with a subnormal growth velocity, generally below about 5 cm per year before puberty, together with delayed bone age and preserved weight-for-height. Familial short stature shows normal velocity and bone age.

Question 20Growth and Development

Which fine motor milestone is typically present at 12 months of age?

  1. Pincer grasp of a small pellet Correct answer.
  2. Copying a circle
  3. Drawing a person with three body parts
  4. Building a tower of six cubes

Explanation

A neat pincer grasp using the thumb and index finger emerges between about 9 and 12 months. It reflects developing fine coordination and is a key milestone of the first year.

Question 21Growth and Development

A boy's father is 170 cm tall and his mother is 160 cm tall. What is his midparental (target) height?

  1. 158.5 cm
  2. 171.5 cm Correct answer.
  3. 165.0 cm
  4. 178.0 cm

Explanation

For boys, midparental height equals (father's height + mother's height + 13 cm) divided by 2, which gives (170 + 160 + 13)/2 = 171.5 cm. The target range is this value plus or minus 8.5 cm.

Question 22Growth and Development

Most infants born small for gestational age without a syndromic cause show catch-up growth by which age?

  1. 6 weeks
  2. 6 years
  3. Catch-up never occurs
  4. 2 years Correct answer.

Explanation

About 85% to 90% of infants born small for gestational age catch up in weight and length, usually within the first 2 years. Those still short at 2 to 4 years warrant endocrine evaluation and are at risk for later metabolic disease.

Question 23Growth and Development

An 8-year-old girl has breast development, a growth spurt, and a bone age of 11 years. Which is the best next step?

  1. Growth hormone therapy to preserve adult height
  2. Repeating the bone age in 12 months
  3. LH, estradiol, and pelvic ultrasonography Correct answer.
  4. Reassurance, since thelarche at 8 years is normal

Explanation

Breast development before 8 years with growth acceleration and a bone age advanced by more than 2 years indicates progressive precocious puberty, which requires biochemical and imaging evaluation such as LH, estradiol, and pelvic ultrasonography. Early treatment with a GnRH analog preserves adult height.

Question 24Growth and Development

Which description corresponds to Tanner breast stage 4?

  1. Enlargement of the breast and areola with no separation of contour
  2. Areola and nipple forming a secondary mound Correct answer.
  3. Mature adult breast contour with projection of the nipple
  4. Breast bud with slight enlargement of the areola

Explanation

In Tanner breast stage 4 the areola and nipple project to form a secondary mound above the contour of the breast. Stage 5 is the mature contour with projection of the nipple alone.

Question 25Growth and Development

Which measurement defines microcephaly in a 12-month-old?

  1. Less than 2 SD below the mean Correct answer.
  2. Below the 25th percentile
  3. No increase in size between two measurements
  4. Smaller than the chest circumference

Explanation

Microcephaly is head circumference more than 2 standard deviations below the mean for age and sex, roughly below the 3rd percentile. Values between -2 and -3 SD are mild and below -3 SD are severe.

Question 26Preventive Pediatrics

A term newborn weighing 3.2 kg is born to a mother who is HBsAg negative. When should the first dose of hepatitis B vaccine be administered?

  1. At hospital discharge, usually day 2
  2. At the 2-month well-child visit
  3. At the 1-month well-child visit
  4. Within 24 hours of birth Correct answer.

Explanation

Hepatitis B vaccine is recommended for every medically stable newborn weighing at least 2000 g, with the first dose given within 24 hours of birth regardless of maternal HBsAg status. Early administration protects infants who may be exposed perinatally and improves completion of the three-dose series.

Question 27Preventive Pediatrics

For a healthy term newborn with no symptoms, when is the standard dried blood spot newborn screening specimen collected?

  1. At the 1-week visit, once milk intake is established
  2. At 2 months of age, alongside the first immunizations
  3. At 24 to 48 hours of age, after feeding begins Correct answer.
  4. Immediately after delivery, from the umbilical cord

Explanation

The specimen is collected between 24 and 48 hours of age after the infant has begun feeding, because metabolic markers are interpretable only once nutrient intake has started. Collection before 24 hours is more likely to produce false results and may require a repeat specimen.

Question 28Preventive Pediatrics

A 6-week-old infant is exclusively breastfed. What vitamin D supplementation is recommended?

  1. 200 IU daily, started when solid foods are introduced at 4 to 6 months
  2. 400 IU daily, started in the first days of life Correct answer.
  3. 400 IU weekly, started at the 2-month well-child visit
  4. 800 IU daily, started at birth and continued for 6 months

Explanation

Human milk contains little vitamin D, so exclusively and partially breastfed infants should receive 400 IU of vitamin D daily beginning within the first days of life. Supplementation continues until the infant consumes at least 1 L per day of vitamin D-fortified formula or milk.

Question 29Preventive Pediatrics

Which sleep practice is recommended to reduce the risk of sudden infant death syndrome in a healthy term infant?

  1. Prone for naps and supine at night
  2. Using a firm pillow to keep the head elevated
  3. Supine on a firm surface, room sharing Correct answer.
  4. Bed sharing with parents until 6 months

Explanation

Infants should be placed supine for every sleep on a firm, flat surface without soft bedding, ideally in a separate sleep space in the parents' room for the first 6 months to 1 year. Prone or side-lying sleep and bed sharing are associated with higher SIDS risk.

Question 30Preventive Pediatrics

For a healthy child with no contraindications, at what age is the first dose of measles-mumps-rubella vaccine routinely given?

  1. 4 through 6 years
  2. 12 through 15 months Correct answer.
  3. 18 through 24 months
  4. 6 months

Explanation

The first MMR dose is given at 12 through 15 months, when residual maternal antibody has waned enough for an adequate immune response, and the second at 4 through 6 years. A dose given at 6 months is reserved for travel or outbreak situations and does not count toward the routine series.

Question 31Preventive Pediatrics

At what age should fluoride varnish application begin for a child at average risk for dental caries?

  1. At the 3-year well-child visit
  2. When the first tooth erupts Correct answer.
  3. After all primary teeth have erupted, near 30 months
  4. At 6 years, when the first permanent molars erupt

Explanation

Fluoride varnish is applied every 3 to 6 months starting when the first tooth erupts, because caries can develop as soon as teeth are present. It is paired with counseling about brushing with a smear of fluoride toothpaste.

Question 32Preventive Pediatrics

How long should a typically developing child ride in a rear-facing car safety seat?

  1. Until 12 months of age, regardless of size
  2. Until the child can sit independently, usually 6 months
  3. Until age 2 years or the seat's height and weight limit Correct answer.
  4. Until the child outgrows the infant carrier, often 9 months

Explanation

Children should ride rear-facing until they reach the highest height or weight allowed by their seat, and at minimum until age 2 years, because rear-facing seats distribute crash forces across the back and head. A forward-facing harnessed seat is the next step, followed by a booster seat.

Question 33Preventive Pediatrics

When should pulse oximetry screening for critical congenital heart disease be performed in a healthy newborn?

  1. At the first office visit, around 3 to 5 days
  2. At 24 to 48 hours of age, before discharge Correct answer.
  3. Only if a murmur is heard on examination
  4. Before the first feeding, within 2 hours of birth

Explanation

Pulse oximetry screening is performed at 24 hours of age or later and before discharge, because earlier measurements may be falsely abnormal during the transition from fetal circulation. Screening identifies ductal-dependent lesions that a routine examination can miss.

Question 34Preventive Pediatrics

A healthy 11-year-old receives the first dose of human papillomavirus vaccine today. Which schedule completes the routine series?

  1. A second dose 6 to 12 months later Correct answer.
  2. Three doses at 0, 2, and 6 months for all adolescents
  3. One dose is sufficient if given before age 15
  4. A second dose 1 month later, then a third at 6 months

Explanation

Adolescents who begin the HPV series before their 15th birthday need two doses, with the second given 6 to 12 months after the first. Three doses are required when the series starts at age 15 years or older, or in immunocompromised patients.

Question 35Preventive Pediatrics

At which well-child visits should standardized screening for autism spectrum disorder be performed?

  1. 18 and 24 months Correct answer.
  2. 4 years only
  3. 9 and 12 months
  4. 12 and 36 months

Explanation

Standardized autism screening is recommended at the 18-month and 24-month well-child visits, alongside developmental surveillance at every visit. Screening at 24 months captures children whose symptoms emerge or regress after 18 months.

Question 36Preventive Pediatrics

At what age should a healthy term infant be screened for anemia with a hemoglobin measurement?

  1. 12 months Correct answer.
  2. 4 months
  3. 24 months
  4. 3 years

Explanation

Universal hemoglobin screening is recommended at approximately 12 months, when maternal iron stores are exhausted and dietary iron may be insufficient. Earlier risk-based testing is reserved for preterm infants and other high-risk groups.

Question 37Preventive Pediatrics

A 10-year-old has no family history of premature cardiovascular disease and a normal BMI. What lipid screening does the AAP recommend?

  1. Non-HDL cholesterol now, repeated at 17 to 21 years Correct answer.
  2. A fasting lipid panel every year beginning at age 2 years
  3. Testing only if the blood pressure is above the 95th percentile
  4. No testing unless a parent has a high cholesterol level

Explanation

Universal lipid screening is recommended once between 9 and 11 years and again between 17 and 21 years, using a nonfasting non-HDL cholesterol level as the initial test. Universal screening detects children with familial hypercholesterolemia who would be missed by family-history-based approaches.

Question 38Preventive Pediatrics

At what age can optotype visual acuity screening with an eye chart first be reliably performed in most children?

  1. 3 years Correct answer.
  2. 7 years
  3. 18 months
  4. 6 months

Explanation

Optotype acuity testing with Lea symbols or a similar chart is generally feasible from about age 3 years. Instrument-based photoscreening can be used for younger or preverbal children who cannot cooperate with acuity testing.

Question 39Preventive Pediatrics

A woman is 28 weeks pregnant with her second child. What is the recommended tetanus-diphtheria-acellular pertussis vaccination?

  1. In the immediate postpartum period
  2. Only during the first pregnancy, with boosters every 10 years thereafter
  3. At 20 weeks of gestation
  4. At 27 to 36 weeks of each pregnancy Correct answer.

Explanation

Tdap is given during every pregnancy at 27 through 36 weeks, regardless of the interval since the last dose, so that maternal antibody crosses the placenta before delivery. This protects infants who are too young to be vaccinated against pertussis.

Question 40Preventive Pediatrics

At what age does annual influenza vaccination first become recommended for healthy children?

  1. 2 years
  2. 5 years
  3. 12 months
  4. 6 months Correct answer.

Explanation

Annual influenza vaccination is recommended for everyone aged 6 months and older, including healthy children. Infants younger than 6 months are protected indirectly through vaccination of household contacts and of the mother during pregnancy.

Question 41Preventive Pediatrics

A 12-month-old enrolled in Medicaid has never had a lead test. What does federal Medicaid policy require?

  1. Testing only if a sibling has an elevated lead level
  2. A single test at 5 years of age
  3. Blood lead testing now and again at 24 months Correct answer.
  4. No testing unless pica is reported

Explanation

Federal Medicaid policy requires blood lead testing at 12 and 24 months for enrolled children, and at 3 through 6 years for those who have never been tested. Capillary results of 10 mcg/dL or higher require confirmation with a venous sample.

Question 42Preventive Pediatrics

A 9-year-old boy has a BMI at the 96th percentile for age and sex. How is this classified?

  1. Severe obesity
  2. Obesity Correct answer.
  3. Normal weight
  4. Overweight

Explanation

BMI at or above the 95th percentile for age and sex defines obesity, while the 85th to below the 95th percentile defines overweight. At least 120% of the 95th percentile defines severe obesity, which warrants more intensive evaluation.

Question 43Preventive Pediatrics

Which statement reflects recommended preventive care for a 14-year-old at a routine well visit?

  1. Tobacco and e-cigarette use are asked about at every visit Correct answer.
  2. Nicotine screening starts at age 18 years
  3. Screening is needed only if a parent smokes
  4. E-cigarette use is asked about only if symptoms are reported

Explanation

Screening for tobacco, e-cigarette, alcohol, and other substance use is recommended at every adolescent well visit, with brief counseling and referral to treatment when use is identified. E-cigarette use is common and is often not disclosed unless specifically asked about.

Question 44Preventive Pediatrics

At what age should routine blood pressure measurement begin at well-child visits for a healthy child?

  1. 10 years
  2. 3 years Correct answer.
  3. 13 years
  4. 6 years

Explanation

Blood pressure should be measured at least annually beginning at age 3 years, and at every visit for infants and children with conditions that predispose to hypertension. Earlier measurement is reserved for high-risk children such as those with congenital heart or renal disease.

Question 45Preventive Pediatrics

A newborn fails the initial hearing screening before discharge. What is the most appropriate next step?

  1. Immediate referral for cochlear implant evaluation
  2. No further testing until the 12-month well-child visit
  3. Referral to otolaryngology for tympanostomy tube placement
  4. Repeat screening or diagnostic ABR by 3 months Correct answer.

Explanation

An infant who does not pass the initial screen needs rescreening or diagnostic auditory brainstem response testing by 3 months of age, with intervention beginning by 6 months when hearing loss is confirmed. Delayed diagnosis impairs language development.

Question 46Preventive Pediatrics

A 16-week-old infant has received no rotavirus vaccine. What is the correct approach at today's visit?

  1. Give one dose today, since a single dose provides adequate protection
  2. Give dose 1 today, then dose 2 in 4 weeks and dose 3 at 6 months
  3. Give dose 1 today and finish the series before 8 months of age
  4. Do not start the series; the age limit for dose 1 has passed Correct answer.

Explanation

The first rotavirus dose must be given by 14 weeks 6 days of age, and the series must be completed by 8 months 0 days, because the risk of intussusception increases with age at vaccination. When the window is missed, the series is not started.

Question 47Preventive Pediatrics

Which pulse oximetry result meets the criteria for a failed newborn screen for critical congenital heart disease?

  1. 96% in the right hand and 98% in a foot
  2. 97% in the right hand and 96% in a foot
  3. 89% in the right hand and 95% in a foot Correct answer.
  4. 95% in the right hand and 95% in a foot

Explanation

A screen fails if oxygen saturation is below 90% in either the right hand or a foot, or if it is 90% to 94% in both locations or differs by more than 3% between sites on repeated measurements. A failed screen requires prompt echocardiography.

Question 48Preventive Pediatrics

An asymptomatic 18-year-old woman who is sexually active with a male partner presents for a well visit. What screening is recommended?

  1. Testing every 3 years after the first episode of intercourse
  2. Annual chlamydia and gonorrhea testing Correct answer.
  3. A Pap test with reflex human papillomavirus testing
  4. Testing only if she reports discharge or dysuria

Explanation

Annual chlamydia and gonorrhea screening is recommended for sexually active women aged 24 years and younger, and for older women at increased risk, because most infections are asymptomatic and untreated infection can cause pelvic inflammatory disease and infertility. Cervical cancer screening begins at age 21 and does not test for these organisms.

Question 49Preventive Pediatrics

A 1-month-old former 30-week preterm infant is exclusively breastfed. What iron supplementation is recommended?

  1. None, because breast milk supplies adequate iron
  2. 1 mg/kg/day begun at 6 months
  3. 6 mg/kg/day begun at 4 months
  4. 2 mg/kg/day begun by 1 month Correct answer.

Explanation

Preterm infants have low iron stores and higher requirements, so 2 mg/kg/day of elemental iron is recommended beginning by 1 month of age and continuing through 12 months, often as a multivitamin with iron. Term breastfed infants receive 1 mg/kg/day starting at 4 months until iron-containing foods are established.

Question 50Preventive Pediatrics

A 5-year-old who immigrated from a high-tuberculosis-burden country has a 12-mm tuberculin skin reaction, no symptoms, and a normal chest radiograph. What does this represent?

  1. A false-positive result that requires no action
  2. Active pulmonary tuberculosis requiring isolation
  3. Latent tuberculosis infection requiring treatment Correct answer.
  4. A BCG-related reaction that should be disregarded

Explanation

A tuberculin reaction of 10 mm or more in a child from a high-prevalence country indicates infection; with no symptoms and a normal chest radiograph, this is latent tuberculosis infection. Treatment with rifampin or isoniazid prevents progression to active disease.