Definition of "Developmental delay"

Last modified: less than a minute

Developmental delay (aka delayed milestone) is where a child doesn't reach 1 of the milestone stages at the expected age, which can be in one of the 4 developmental domains:

However, a wide variety of ages can be considered normal, and not a cause for medical concern. Milestones are often measured using percentiles, and milestones between the 5th and 95th percentile don't require intervention, but values towards the edges of that range can be associated with other medical conditions. It is not possible to treat.

Global developmental delay (GDD) is delay that occurs in 2 or more developmental domains.

Patient information

What is developmental delay, and GDD?
It's where there are delayed milestone in 1 of the 4 domains, so that's gross motor, fine motor, language, and social. People have also come up with extra ones, but these are the biggies. GDD is where there is delay in 2 or more of these 4 domains.

Wait. You said language and social, aren't these 2 things basically autism?
It is, but the diagnosis of autism requires that it's not better accounted for by GDD .


Developmental milestones are recognized norms of pattern of development that children are expected to follow. In premature infants (<37 weeks gestation), we use corrected gestational age until 2yo.

The 7 developmental domains include:

  • Gross motor
  • Fine motor
  • Language and speech, where language delay is the failure to develop language abilities, cf. speech delay where the speech mechanism itself is the focus of delay
  • Social and emotional
  • Also:
    • Cognition (thinking)
    • ADL's, i.e. self-help and adaptive
    • Spiritual and moral

A mnemonic that can be used to memorize is at 1yo, single words. At 2yo, and parallel play (2 things). At 4yo, counts 4 objects.

  Gross motor Fine motor Speech Social
6wk Lifts chin occasionally when prone     Social smile
2mo Arms extend forward when prone Pulls at clothes Cooing sounds  
3mo Moro reflex gone      
4mo Rolls from front to back Reaches, pulls objects to mouth Responds to human voice  
6mo When prone, can put weight on hands Ulnar grasping Responds to name. Babbling starts Stranger anxiety
9mo Pulls to stand Finger-thumb grasping "Mamma, Dadda" Separation anxiety
12mo Walks under support Pincer grasp. Throws. Babinski begins to disappear 2 words beyond "Mama, Dadda", so a word with meaning Drinks with cup
15mo Walks without support Draws line Jargon Points to needed items
18mo Climbs steps with support Scribbling Says own name. 10 words Uses spoon
2yo Runs. Kick ball. Climb 2 steps Undresses 2 word sentences, with pronouns. Favorite word is "No" Parallel play
3yo Ride tricycle Copies a circle Prepositions All dress/undress except buttons
4yo Hop on 1 foot Copies a cross Tells story Cooperative play. Toilet trained. Buttons clothes
5yo Skip. Catch ball Copies a square. Prints own name. Ties shoelaces Alphabet. Future tense Oedipus complex
6yo Rides bicycle Copies a triangle Begins reading Develops right vs wrong sense

Source: Clinical exam

Patient information

Gross motor. What's that, and how does that change over time?
So that's large movements bub makes with their arms, legs, feet, or whole body. So we start with the major land mark, whcih is 12mo, which involves walking with support. Working backwards, at 9mo, they pull to stand. At 6mo, sit put weight on hands, which can be memorized because "sit" sounds like "six", as well as 6 looking like someone sitting. At 4mo, start rolling. At mo, extend their arms forward. We can memorize this with the mnemonic that myelination of nerves happens from head to toe during the 1st year of life, which is why things start with head support, rolling using arms, sitting using waist, and crawling using knees, and so forth. Going the other way, at 15mo, walks without support. At 18mo, climb steps with support. At 2yo, run, and climb steps at 2yo, memorized by 2 steps at 2yo. At 3yo, tricycle, which can be memorized by 3 wheels at 3yo. At 4yo, hop, which can be memorized by a kid with their knees bent like a "4" (to hop), and playing "hop 4". At 5yo, skip, that can be memorized by the fact "5" looks like "S". At 6yo, ride a bike.

Fine motor. What about that?
So that's using the smaller muscles of the hands, fingers, and of course the eyes. So we start with the major land mark at 12mo, which is the pincer grasp and throwing. So working back, at 9mo, there's the whole-hand grasp. At 6mo, there's ulnar grasp, where you grab without using the thumb. At 4mo, reaching, and pulling objects to mouth. At 2mo, pulling at clothes. Going the other way, at 15mo, they can draw a line. At 18mo, they can scribble. At 2yo, they undress. At 3yo, they can copy a circle. At 4yo, they can copy a cross. At 5yo, they can copy a square, write their name, and tie shoelaces. At 6yo, they can copy a triangle. The shapes can be memorized from 3-6, involving a stick figure with a circle face at the top, a cross hanging on the neck, a square body, and a triangle skirt.

Speech. So that's talking, right? Can bubs talk lol?
Well eventually they can, right ? Remember that it also includes listening too . So the big landmark is 1yo, where bub can say 2 words beyond "mama, dada". At 9mo, they can say "mama, dada". At 6mo, they start to babble, and they can also respond to their name. At 4mo, they respond to human voice. At 2mo, they coo. At the other end, at 15mo, they speak jargon, so it's context specific. At 18mo, they can say their own name, and 10 words. At 2yo, 2 word sentences, around 200 words (2 zeros), and understand 2 step commands. At 3yo, they can speak 1,000 words (3 zeros), use 3 word combinations (and therefore use preopositions), and repeat 3 digits. At 4yo, they can count 4 objects, and tell a story. At 5yo, they can say the alphabet. At 6yo, they begin reading.

Social. Is that how bubbly they are ?
So the big landmark is 1yo, where they can drink with a cup. At 9mo, they have separation anxiety. At 6mo, they have stranger anxiety. At 6 weeks, they have a social smile. At the other end, at 15mo, they point to needed items. At 18mo, they can use a spoon. At 2yo, they have parallel play, where children play alone but are interested in what other children are doing. At 3yo, they can dress and undress, except for buttons. At 4yo, they have cooperative play, are toilet trained, and can buton clothes. At 5yo, they have oedipus complex, where they have sense of rivalry with a same gender parent. At 6yo, they develop sense of difference between right and wrong.

Wait. Why are you doing this up to 6 months? You being a bit lazy ?
It's why we do it. We do it because under the age of 6, they bub can't readily express themselves, so we use this to find out what's going on with them. Also, they start going to school, so things become more obvious when they're around others all day.

Source: Mamaye

Patient information

So let's just talk about how I should go about memorizing this ?
Once you've remembered it based on each of the 4 domains, you can then remember it based on the other dimension, which is age, so at 1, 6, and 9 months. Also 1, 2, 3 and 4 years. Keep those landmarks in mind. The most important is 1 year old.

What happens at 1 year old?
They can walk alone. Use 2 fingers in a pincer grip. Say mama and dada. And imitate a parent. That's where we want them to be .

Let's go down to the short end. 1 month. What do we expect?
Not a lot, obviously . Lift their head. Track things with their eye. Coo. And recognize their parents.

What happens part way between then? At 6 months?
It's the stuff in between. So what's between lifting their head and walking? Sitting up. What's between not using their hands and a pincer grip? A raking grasp. What's in between cooing and saying mama/dada? Babbling. What's in between recognizing parents and imitating parents? Recognizing strangers.

How about between 6 and 12 months?
Again, it's the stuff in between. So in between sitting up and walking, is walking with assistance. In between raking grasp and a 2 finger prince grip, is a 3 finger pincer grip. Language we sort of ignore here. And in between stranger anxiety and imitating their parent, is interacting with parents, such as waving bye-bye or play "pat-a-cake" with parents.

That sub-division type strategy made memorizing a lot more easier . But how about as you go up to 2 years of age?
It's easy because it correlates with the age. Climb 2 steps. Say 2 word phrases. Follow 2 step commands. And the only exception - stack 6 blocks.

So 3 years would be the year of 3's?
Yep! Ride a tricycle. Say 3 word sentences. Copy a circle, which can be memorized with the fact that it is a 360 degree angle! For fine motor, they should be able to draw a person with as many parts as their age - for example, a face, eyes, and mouth. And, they can brush their teeth.

So a 4 year old can add a nose to their picture?
Yep. Also, they can hop. Copy across. And play with other kids.

Source: UndergroundMed

  • There is usually a more specific condition which causes this delay, e.g. Fragile X syndrome, or other chromosomal abnormalities
See also

Find a practitioner

Practitioner count: 0
Sponsor a disease. And see how your proceeds help.
Express interest
Write text
Write FAQ
Snap photos
Record audio
Produce video
Interview experts

Definition of Developmental delay | Autoprac

RSS feeds: Most recent Most viewed