By the age of 15 months, a parent should check for the following symptoms and in case of lacking criteria, one should immediately seek advice from a pediatrician.
General Screening
Observe if the child sits without any assistance.
Observe if the child recognizes the top and bottom of a toy.
Observe if the child says monosyllables.
Observe if the child is attached to mother and reflects any signs of resentment over separation.
Observe if the child walks alone.
Observe if the child says dada, mama and 5-6 common words like water, milk, car, door, names or sibling.
Observe if the child looks for objects hidden from sight.
Observe if the child assists or co-operates when dressing.
Vision Screening
Place a thread or small pellet (smaller than used for 6 months) on the table and observe if the child picks it up.
Hearing Screening
Take a test where one person distracts the child’s attention while the other makes sound with a rattle on both sides alternately above and below at 3-6 feet behind at the infant’s ear level. Now observe in the child turns head towards the sound.