Episode Transcript
Hi and Welcome to Clerkship Ready - Pediatrics - A podcast aimed at helping you excel during your clinical clerkship in Pediatrics.
I am Dr. Rachel Moon and I am a general pediatrician and Professor of Pediatrics at the university of Virginia.
Today, we will be reviewing overall child development.
Why is it important to learn about development?
Besides the fact that questions about child development are favorite questions on shelf exams, step 2, and board exams, it’s an integral part of what we as pediatricians – and you as a medical student on your clerkship – will do every single time you walk into the room. Assessing a child’s development is considered by pediatricians to be part of the complete physical exam. It’s a part of the puzzle of being able to assess normal from abnormal. Whether the child is developing normally or not will impact your differential diagnosis for just about any illness.
Here’s an example of how knowledge of development will impact your differential diagnosis. You are seeing a 2 month old with a large bump on the head. The parents report that the baby rolled off the bed and hit their head on the floor. When you examine the baby, there is a step-off of the skull bones, making you concerned about a skull fracture. What is your differential diagnosis for a skull fracture in a 2 month old? Accidental and non-accidental trauma are certainly going to be on the list. If you know that rolling is a motor milestone that very few 2 month olds have attained, as it usually is not attained until the infant is 3 or 4 months old, the history from the parents should put non-accidental trauma higher on your differential, because the history is inconsistent with the physical exam findings.
You also will get a lot of questions from parents about their child’s development. For instance, it is not uncommon that a parent will say at the 12 month well check, “She’s not talking yet” or “He’s not walking yet” and want you to reassure them that this is within normal limits. AND last but definitely not least, early recognition of developmental delay and referral to appropriate specialists and resources is key to the child’s overall health, well being, and future success in learning.
The Centers for Disease Control and Prevention, or CDC, estimates that about 1 in 6 children has a developmental disability. Only 1/4 of these are identified before the age of 3 years, and fewer than half of these children are identified as having a problem before starting school. Identifying developmental delays early is a very important part of allowing us to intervene early and therefore change the trajectory of children’s lives. Because early treatment can make a big difference in a child’s ability to learn new skills, early referral and early treatment are very important for children with developmental disabilities. Speech therapy, physical therapy, and other services are available in every state for free or at low cost to parents, often through a program called Early Intervention. However, if a developmental concern is not identified early, parents can't take advantage of these services.
We assess development at each visit until the age of 5 years. At that point, the vast majority of children are in school, and the school takes over the primary responsibility for identifying new developmental or learning problems. Let’s start to review some terms that you will hear a lot in relation to developmental milestones. Surveillance versus screening versus diagnosis.
Developmental surveillance is when we monitor development in a longitudinal process at every visit. When we do developmental surveillance, we ask about concerns, take a developmental history based on milestone attainment, observe milestones and other behaviors, examine the child, and use our clinical judgment to decide if a child may be at risk for delays and when additional developmental screening might be warranted.
Developmental screening involves the use of validated screening tools at specific ages or when surveillance reveals a concern. It is more formal, it is done by medical professionals in primary care offices and it is recommended by the American Academy of Pediatrics, or AAP, for all children at ages 9, 18, and 30 mos. Autism-specific screening, using a validated autism screening tool, is also recommended at ages 18mo and 24mo. Onevvalidated screening tool that is commonly used is the Ages and Stages Questionnaire for routine developmental screening. A common autism screening tool is the MCHAT, or Modified Checklist for Autism in Toddlers.
If a child is deemed to be at risk for developmental delay through the surveillance and screening processes, then a diagnostic evaluation is done, typically by a developmental specialist, to further evaluate and diagnose developmental delays.
We often use milestone checklists to guide our developmental surveillance, but unlike the tools that we use for screening and diagnosis, these checklists are usually not validated. The AAP and CDC in 2022, updated and revised the developmental milestones checklists. The CDC Developmental milestones checklist uses the 75th percentile for the milestones at each age. In other words, 75% of children are expected to be able to do each of the activities on the checklist for each age. This is different from some of the other milestone checklists, which use 50%ile. With the checklists that use the 50%ile, as we’ll talk about at the end of this episode, many clinicians will monitor for a few months before deciding whether to refer to early intervention services. The new CDC developmental milestones use the 75%ile specifically to discourage this wait-and-see approach, and it is hoped that children will be referred earlier.
You should know that there is a developmental milestone checklist for every health supervision visit from ages 2 months to 5 years but each practice may be slightly different in what they use, so check with your resident or attending as to what is being used in your practice. Also, the most recent revisions of milestone checklists now have open-ended questions, because developmental surveillance involves more than checklists. These questions are there to help you initiate conversations about development that are based on the child’s and family’s strengths and to develop trust with parents about their child’s development. Sometimes parents don’t report concerns about development because they feel that it reflects on their parenting or home environment. So these questions can help to identify concerns that a checklist alone won’t capture.
There are 4 major categories that we assess in our developmental surveillance and screening: Social/Emotional, language/communication, cognitive, and movement/physical development. Let’s quickly describe these 4 categories, or domains.
First, Social/Emotional. This domain is about how children interact with others and show emotion. This begins with smiling when talked to or smiled at, laughing, recognizing people, stranger anxiety, and showing affection.
Language/Communication. This domain is about how children express their needs and share what they are thinking, as well as understand what is said to them. Hearing is a big part of language and communication. If you can’t hear well, your language skills will reflect that. Language skills can be divided into expressive and receptive language. Expressive language is how you express yourself – so words and sentences. Receptive language includes hearing, of course, but also understanding. Language and communication milestones include cooing, babbling, saying words, waving bye, pointing to body parts, and following commands. Language can be spoken or sign language.
The cognitive domain is the learning, thinking, and problem-solving domain. This domain is about how children learn new things and solve problems. It includes how children explore their environment to figure things out – whether by looking at the world around them, putting objects in their mouths, or dropping something to watch it fall. This domain also includes “academic” skills like counting and learning letters and numbers.
The Movement/Physical Development domain is about how children use their bodies. It includes many milestones that parents excitedly wait for. This domain is further broken down into
Gross motor: this is how you use all of your big muscles – so head control, rolling over, sitting, crawling, standing, walking, running – and
Fine motor: this is basically hand/eye coordination – using your vision to see what you’re doing and then using your fingers to manipulate objects. This would include activities like reaching, grabbing, and letting go of objects.
Some developmental milestones fit more than one domain.
For example:
Pretending to be something else, like a teacher, superhero, or dog, during play with others – which is a 4 year old milestone - can be a social/emotional milestone and a cognitive milestone;
Following directions, for example 2-step commands, which is a 2 year old milestone - can be a language/communication and a cognitive milestone; and
Playing peek-a-boo, which is a 9-12 month milestone, can be a cognitive and a social/emotional milestone.
You will want to ask about activities in each of these 4 domains. Many practices will have parents complete a checklist before or during the well child visit, so you can refer to that. If there are delays in one category of development vs. delays in more than 1 category, that changes your differential and changes your management of the patient. For instance, if you have a child with isolated delays in language and communication but is meeting milestones in all of the other categories, hearing loss will be high on your differential. However, if you have a child with delays in both language & communication, and social/emotional skills, autism spectrum disorder will be high on your differential.
So how do you learn the milestones? We’re going to go through some of the major milestones in a few minutes, but before we do that, I want to go over a couple of suggestions and general comments:
1) We usually classify milestones based on when we see them for well child visits. So it will be helpful for you to learn the schedule for well child visits. These visits are timed, both so that we can check on growth and development, but also so that we can give vaccines. After the newborn period, we see babies every 2 months: so 2, 4, and 6 months. As the rate of growth and development starts to slow down, we begin spacing the visits out. After the 6 month visit, we see patients every 3 months: so 9, 12, 15, and 18 months. Then we go to every 6 months for 24, 30, and 36 months. Beginning at 36 months – or 3 years, we go to every year.
2) If you know any young children, watch them for a few minutes to see what they can do. That will help you remember those specific ages. It can also be fun to watch them before you know how old they are and then try to guess their approximate age before you ask the parent. It’s also a good idea to try to see patients of all different ages during your pediatric clerkship, so that you can observe what they are doing and get a feel for what is normal. So don’t just look at the milestones – look at the child, and seeing what they are doing will help you to cement these milestones in your memory.
3) The milestones that we’re going to go through are the ages when most children attain these. Of course, there is going to be a range – some children will attain specific milestones earlier, while others attain them a little bit later.
OK, let’s go through some of the major milestones in each category. Where I have tricks to remember milestones, I’ll tell you, and for others where I don’t have tricks, I will try to relate them to other aspects of growth and development, so that it’s easier for you to remember. After we go through the major milestones, we’ll go through some case scenarios that illustrate some of the common questions that you may get during your clerkship.
Let’s start with gross motor development. I think that these are the easiest to remember, and again, these are often the ones that parents really focus on. In the first year of life, children develop their gross motor skills from head to toe. In terms of gross motor development, the goal of the first year is for the child to walk. In the first 3 months, the baby gains control of their head and neck. So by 3 months, they should be able to hold their head steady when they’re in an upright position. They should also be able to lift their head when they are placed on their stomach, such as when they are awake and in tummy time. In the next 3 months, the baby gains control of their trunk. They begin to lift their chest and upper abdomen when they’re in tummy time. At around 4 months, they can roll over. Then they begin sitting – first they need to support themselves by using a tripod position, with their arms extended and on the floor in front of them. By 6 months, they can generally sit unsupported for at least a few seconds. In the next 3 months, think knees. So by 9 months, they generally begin crawling. In the next 3 months, think feet. They first pull themselves up to a standing position, then walk holding on to something – which we call cruising – and then by 12 months, they are beginning to walk unassisted, at least for a few steps.
After the first year, gross motor milestones are focused on locomotion. By 18 months, children develop the ability to run, and by 2 years – or 24 months – of age, they start to hop – or jump on 2 feet. I remember running at 18 months by thinking of Olympic jumpers, who run before they jump. And I remember jumping at 2 years, because you have 2 feet leaving the ground at 2 years old. I know that’s not very good, but it works for me! The 3 year gross motor milestone is easy to remember – it’s being able to ride a tricycle. A tricycle has 3 wheels for 3 year olds. And then 4 year olds can balance and hop on 1 foot. I remember this because if you are standing on one foot in a tree yoga pose – which is when one leg is bent at the knee, with the bottom of the foot touching the straight leg – the legs form a shape that looks like the number 4.
OK, so those are some of the major gross motor milestones.
Let’s now move to fine motor milestones. Remember, these are all about hand/eye coordination. In the first couple of months, we focus on whether the babies seem like they can see. If you move an object in front of their face, do their eyes follow to see where the object goes? At around 2 months, the babies will discover their hands. Before this, they will grasp something that is put into their hands – this is called the palmar grasp reflex and not a voluntary skill, but at around 2 months, they will start using their hands to swipe or hit objects, such as in a mobile. They will also realize that they have hands and stare at their hands. At 3-4 months, the grasp reflex will also start to go away, and so they will be able to let go of objects as well. At around 4 to 6 months, they will start to reach for objects with their whole hand. Their fingers will be like a rake, and they’ll use what is called a raking motion to bring small objects closer to them. Often, they will try to bring their hands and/or these objects to their mouth. Conveniently, this is around the time when babies start to eat foods other than human milk or formula. But it also means that you have to make sure that they can’t get to objects that they may choke on. By 9 to 12 months, they will have discovered their thumb and will pick up things with the tips of their thumb and index finger – this is called a pincer grasp. The pincer grasp is well developed by age 12 months in most children.
Starting at around 1 year is when most have started to transition from pureed baby foods to foods that are more like what their family is eating. They can use their pincer grasp to pick up what we call finger foods – foods that can be picked up with the fingers. So in my mind, just like the baby’s gross motor goal at the end of the first year is to walk, the baby’s fine motor goal at the end of the first year is to begin to feed themselves. At around 1 year, they also can start to use a cup. Again, this is convenient, because they should transition from using a bottle to a cup at around this time. Somewhere between 18 and 24 months, they should also start being able to use a spoon. They can pick up some food and bring it to their mouth – although not always very precisely or cleanly.
Beginning around 2 years, they can scribble and may be able to draw a few lines. At 3 years, they can draw a circle. They will also start to draw pictures of people – which will basically be a big circle for the head and a few lines for the arms and legs. At 4 years they can draw intersecting lines and maybe a square, and at 5 years, they can start to draw a triangle and maybe write some of their ABCs. It makes sense that they need to be able to draw these different shapes before they can write their letters.
Now let’s talk about language and communication. Remember that hearing is an important part of this. In fact, if a child is not meeting their language milestones, the first thing that you will want to do in your evaluation is to have their hearing tested. Even if they passed their newborn hearing screen, they could still have hearing problems. Delayed onset hearing loss has many causes. Probably the most common is frequent ear infections, or otitis media. These infections can leave behind middle ear effusions, or fluid behind the eardrum, and this can cause conductive hearing loss. I tell parents that when you have a middle ear effusion, it’s kind of like trying to hear when you have water in your ears – or while you’re under water – everything is garbled, and that makes it hard for their children to learn how to understand and say words.
For language, I think that the goal of the first year is to be able to say 1-2 words with intent and meaning. This means that the child intends to say the specific word and it means the same thing each time. So for instance, if a baby says “bababa” but it doesn’t mean anything specific, that does not count as a word. That is babbling, which is an earlier skill – at around 6 months. But if the baby says “baba” consistently to mean “bottle,” that does count as a word.
So let’s see how we get to true words.
By 2 months, babies are communicating by smiling and making sounds other than crying.
At around 3-4 months, they start cooing, which means making vowel sounds like oo, ee, and ah. If you talk to them, they will often make cooing sounds in response. If you remember that coo is a 3 letter word, you can remember that 3 months, babies coo. They will also start laughing. At around 6 months, they start babbling, which we mentioned before. Babble is a 6 letter word, so that may help you remember. They start using consonants – so you’ll hear mama, dada, baba, but without intent or meaning. They will gradually be babbling longer words and start imitating sounds. Then at around 12 months, they will say 1-2 words with meaning. If you put 1 and 2 together, it makes 12. So 1-2 words at 12 months. Children can also understand more words and simple commands at this time. Maybe it’s not surprising that “no” is often one of the first words that children say consistently with intent and with meaning.
At 2, they have about 20-30 words and start speaking in 2-word phrases, such as “more milk,” “no go” and “go bye-bye.” They also can follow 2 step directions – like “pick up the book and bring it to me”, and parents can understand at least 2/4 of what they are saying. So remember at 2 years: 20 words, 2 word phrases, 2 step commands, and 2/4 understandable. You’ll see why I say 2/4 understandable instead of ½ understandable in a minute.
At 3, they use 3-word phrases, and their speech is ¾ understandable.
At 4, they use 4 word sentences, and their speech is totally - or 4/4 - understandable.
OK, the next category of development is social/emotional. The goal of the first year is recognizing that people are individuals that they can interact with. We start by seeing how babies react to people. This starts at 2 months, when they have what is called a “social smile.” This is a smile when they see a person or in reaction to something that person says or does. Then at 4 months, they start to laugh. At 6 months, they are starting to be able to distinguish people. So they recognize people as being familiar or strangers. What do you think will come when they realize that you’re a stranger? That’s right! Stranger anxiety starts at 6-9 months. So when a baby starts to cry when you approach them, you shouldn’t take it personally. By 1 year, they will really start to interact with people, by pointing at objects to get people’s attention and playing games like peekaboo. By 2 years, they will recognize emotion – so they may stop playing and look sad when another child starts crying. They will play next to other children but will probably not play with the other children. This is called parallel play. Think of 2 parallel sticks for parallel play at 2 years. Interactive play, where they play with other children, generally starts at around 3 years. And pretend play, where they play dress up or pretend to be animals, generally starts at around 4 years. Note that children with early signs of autism spectrum disorder often have delays in the social/emotional category of development. They may not interact with people or try to get their attention.
The last category is the cognitive domain. As we said before, this is the learning, thinking, problem-solving domain and how children explore their environment to learn new things and solve problems. Because there is so much overlap with the other domains, many of these milestones are incorporated into surveillance and screening questions for the other domains. So I’m going to try to relate some of these milestones with the others that we’ve gone through. At 2 months, babies can focus on people and on objects – which makes sense, because this is also around the time when they develop a social smile. At 6 months, they are beginning to explore objects – by reaching for them and putting them in their mouths. But they don’t have a sense of object permanence. That comes at around 9-12 months – if a person or object disappears, they look for it. So babies this age love the game peek-a-boo. At 15-18 months, children understand how to use objects, for instance they will begin to stack blocks on top of each other or push wheeled toys around. They will also start to copy what others are doing. At 24 months, they are beginning to understand how objects relate to other objects. For instance, they learn that if they turn a knob or flip a switch, something will happen, like a toy will pop up or a light will turn on. At 30 months, they are developing simple problem solving skills – such as standing on a chair to reach an object. And at 36 months, they are beginning to understand consequences, so if you tell them that something is hot, they will not touch it.
OK, so those are some of the major milestones. Now, let’s go through a few common case scenarios that have some specific teaching points.
You are seeing a 2 year old boy for a checkup. You get the history from the parents using a Spanish-language interpreter. When you ask about what words the child is saying, they tell you that he can only say “no” and “milk.” They ask you if he should be talking more. When you get the social history, you learn that he attends child care, and his child care providers are English and Spanish speaking. The rest of the developmental screen and the physical exam are normal. Do you need to worry about his language development? (PAUSE) This child lives in a multilingual environment. For such children, you want to count the words in all of the languages that they are speaking. So maybe this child has only 2 English words, but 20 or 30 Spanish words. If so, then you can reassure the family that the child is doing just fine with their language skills.
Next case.
You are seeing a 12 month old girl. She was born at 32 weeks gestation and, other than being treated for Group B strep sepsis, she did well in the neonatal intensive care unit. She has been doing well, and the parents have no concerns. When you look at the developmental screening tool, the child cannot take steps on her own, is babbling and says “mama” and “dada,” but the parents don’t think that she knows yet what “mama’ and “dada” mean. Should you be concerned?
The key point here is that, when you have a child who was born preterm, you will add a correction factor for their preterm status until they are 2 years old. We do this for growth as well. So this patient is 12 months old but was born at 32 weeks gestation. Since full term gestation is 40 weeks, she was born 8 weeks – or roughly 2 months – early. Thus, you will expect this child to be meeting milestones – and growth parameters – for a 10 month old, not a 12 month old. So is this child meeting 10 month milestones? Well, we talked about 9 month and 12 month milestones, so you’ll have to do a little extrapolation and maybe get a little more history. You know that walking without assistance is a 12 month milestone. Is she taking a few steps while holding on to something or someone – in other words, is she cruising? If so, that is certainly acceptable for someone who is 10 months corrected age. She is babbling a lot, so that is also acceptable for 10 months corrected age. So this child is ok. As a side note, most babies who are born preterm are automatically referred to early intervention services, where their development will be followed closely, and they can get any needed services from physical, occupational, and/or speech therapists, and developmental specialists.
OK, next case.
You are seeing a little boy for his 3 yo well child visit. He is running around the exam room, and when you ask about the baby that his mother is holding, he says “new baby sissy.” He is very busy in the exam room, running around and jumping up and down excitedly while you are talking to the mother, and so you give him a piece of paper and crayons to draw a picture. He then shows you what he’s drawn – a large circle with a few smaller circles and lines inside the big circle. He proudly tells you that this is his daddy. The mother’s one concern is that he seems to have regressed since his baby sister was born. He used to be fully potty trained, and how he keeps having “accidents” during the day. Otherwise, the rest of the history and your exam is normal. Are you concerned about this developmental regression?
There are a couple of teaching points in this scenario. First, we didn’t talk about potty training, because that doesn’t really fall cleanly into a specific domain. However, it is a milestone usually attained between 2-1/2 and 3-1/2 years of age. Second, observation of what the child is doing while you’re taking the history can give you a great idea of how the child is doing. This 3 year old is running, jumping, and is speaking in 3 word phrases. He can draw circles and lines. These are all right in line with what a 3 year old should be doing. However, there is this developmental regression – or losing skills that they once had. In general, if a child is experiencing developmental regression –that should give you pause. We often will see some mild regression in one category when the child is experiencing some trauma or stress, and having a new baby in the home is certainly a big life change that can cause stress. In this case, given that everything else is normal, I think that you can reassure the mother. However, there are other disease processes that we need to keep in the back of our minds when we see developmental regression, the 2 most common categories being autism spectrum disorder and neurodegenerative disorders.
Finally, I want to spend a few minutes talking about what you do if you see developmental delay.
If you’re using a 50%ile checklist, and the delay is mild or in one category only, you may want to give the parents activities to do at home and then have them return for evaluation at the next well child visit – or sooner. For instance, if there are some mild language delays, you may want to encourage the parent to spend more time talking to the child and responding to the child when they talk – or to spend more time reading books with the child, since that is an evidence-based strategy to improve language skills. If it is just language delay, then a hearing test is probably a good idea. If you’re using the CDC checklist, where 75% of children at that age can do the listed activities, and there is a delay, or there are delays in more than one category, you will obviously need to think about your differential diagnosis. But it will also be important to think about resources and services that may help the child. This often includes physical, occupational and speech therapies, and/or referral to developmental and/or educational specialists. It is never wrong to refer a child for early intervention.
That’s it for this episode. I would encourage you to pay attention whenever there are young children around, and watch what they can and can’t do. You’ll learn a lot about normal development that way!
OUTRO:
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