Development as part of life

We continue to develop new skills throughout life, but it is during childhood, particularly the first 5 years of life, that the majority of basic skills are acquired.

Doctors learning about child development often wish to memorize lists of milestones, but fail to appreciate the diversity of normal variation. We do not expect an even distribution of talents among adults, yet we often assume children all develop similarly. It is the variability in normal patterns of development that makes the area fascinating and creates complex challenges in screening and diagnosis.

Parents know their own children best

Child development starts with a good history. Parents are often remarkably accurate at recalling recent developmental achievements and changes, but more distant events may require prior notice so that sources such as relatives and baby books can be reviewed. A simple questionnaire filled in before the interview can allow parents to consider these details in the waiting room or at home. Parents should be asked open-ended questions

History is everything

A good developmental history starts with the pregnancy and delivery, and progresses through the neonatal, infancy, toddler and preschool years; it should be a routine part of all paediatric interactions. The doctor requires a working knowledge of normal development and needs to be aware of the significance of variations that may indicate a developmental disorder. Child development progresses in many areas simultaneously (Table 2.2.1). It is as necessary to know the various developmental systems as it is to know the physical systems. Each will have its component parts, and the rate of progress in all of these components may be similar (when all are delayed, this is described as global delay) or discrepant (described as a specific delay in one area).

Table 2.2.1 Areas of development

What are the normal ranges?

The key is to look for areas of development delayed beyond the normal range and not to compare the child with ‘normal milestones’, which are merely the average age of achievement. By definition, half of the population will not meet median milestones, and their use can worry parents unnecessarily (‘milestones are millstones’). It is preferable to use the normal ranges in Table 2.2.2. Many developmental patterns are familial, but so are many developmental disorders, so it is unwise to accept delay as a normal variation. Just because an uncle did not talk until he was 4 years old does not mean he did not also have a developmental language disorder or deafness. Other ‘causes’ such as being a twin, bilingualism or tongue-tie can produce minor variations, but not significant delays needing more formal diagnostic assessment. Assuming that the child’s delay is caused by these minor variations is a common source of late diagnosis and delayed effective intervention. The most important conclusion that needs to be drawn from this surveillance is that there are no warning signs of a potential problem (Table 2.2.3). Should doubt exist, it is always better to seek a second opinion and to arrange some therapy or intervention than to provide false reassurance. It may make you feel better to reassure, but families who waste months finding help for their child will often feel let down.

Table 2.2.2 Normal ranges for children’s developmental progress (approximately 25th to 90th percentile)

Table 2.2.3 Warning signs to worry about; be concerned if the child is not doing this (but items marked with an asterisk (*) are a worry if they are present)

Any interaction is an opportunity to examine

As each area is reviewed through the different stages of childhood, any apparent delays or unusual features can be clarified with the family. This allows the developmental examination to be targeted. Although many children are shy and perhaps fearful, a quiet and patient approach will often bring out the show-off in children, especially for tasks about which they are confident. For this reason it is best to start looking at non-verbal areas (blocks, puzzles, drawing, etc.) and having appropriate furniture at the child’s height will enable you to get down to the child’s eye level. Simple equipment (Table 2.2.4) can be used to elicit a range of skills and the session should remain a play activity. Remember that too much direct eye contact, especially from above, can be threatening, and a relaxed tangential approach across the child may be more successful. Refusal to cooperate is a regular occurrence and it is better to reschedule than to persist and teach the child the sessions are going to be unpleasant.

Table 2.2.4 Developmental equipment

The aim of the medical examination (see Chapter 2.1) is to detect any condition that might be causing the developmental delay, or indeed any general medical problem that may be exacerbating it. You should note the child’s growth parameters, especially head circumference, and any signs of dysmorphism or neurocutaneous disorders. Although a thorough physical examination is desirable, particular attention needs to be paid to the neurological system, looking for signs of cerebral palsy and other neuromotor disorders (see Chapter 17.2). Some ingenuity may be needed after a long developmental session to re-engage the child in play.

Vision and hearing are vital for children’s learning. For intervention to be as effective as possible, these senses need to be sharp. It may therefore be of more service to the child to arrange an opinion from a vision or hearing professional than to perform a rough screening test, which can miss minor problems that are easily remediable. Again, avoid false reassurance at all costs.