Most parents treat the infant health check-up as something a text message will remind them about. But this programme has a feature that other health check-ups do not: for each stage, a window opens and then closes. It is not like the adult health check-up, where you can go at any point during the year.

The windows matter more than the number eight

The leaflet says eight free check-ups. Read on its own, that sentence makes it sound like eight visits to be fitted in at some point. The actual structure is different.

Each stage has a defined age range in months in which it can be taken. Once that range passes, the stage lapses and you wait for the next one to open. Catching up on missed stages later is not possible.

So the accurate way to think about the programme is not "eight chances" but "eight windows". Each has a point at which it opens and a point at which it closes.

What is examined changes from stage to stage

The early and later stages are different in character.

• The first stage, at around 14 days — largely about basic health in the newborn period, feeding and the caring environment.
• Stages from four months onwards — this is where the developmental assessment (K-DST) questionnaire comes in, with the carer answering questions on gross and fine motor skills, cognition, language and social skills.
• Later stages (before school entry) — development shortly before starting school, daily routines and immunisation history take up more of the visit.

In other words, the further along you go, the more weight falls on development. Skipping the later stages because a child looks healthy means missing exactly the point at which something could have been picked up.

Dental check-ups are counted separately

This is a frequent source of confusion. Dental check-ups run separately from the general health check-up stages. They are also scheduled into periods that do not overlap with the general check-ups.

So thinking "we have had our check-up, that is done" lets a whole dental stage go by. It is safer to keep the schedule on two lines: one for general check-ups, one for dental.

The providers differ too. General check-ups are done at paediatric and similar clinics; dental check-ups at dental practices designated as check-up providers. Without checking first, you can make the trip and be sent away.

The one line to look for on the result sheet

The result sheet carries a finding. If it says "in-depth assessment recommended" or something to that effect, that is not a note — it is a signal to move to the next step.

In that case a detailed developmental assessment follows, and where income and other eligibility conditions are met, a scheme exists to help with the cost of that assessment. Eligibility and how to apply are explained by your local public health centre.

Many carers read that line and decide to wait and see. But checking at this stage means the time you spend waiting is not simply lost. Being told there is nothing wrong is also a result. How to read the developmental questionnaire itself is set out separately under Language Development.

If you have already missed one

1. First, check with the National Health Insurance Service which stages your child has left and which window is currently open. An eligibility lookup service is provided.
2. Stages that have passed cannot be recovered, so mark the next one in the calendar in advance. Booking in the first month the window opens is the safe approach.
3. If you are worried about development, do not wait for the next check-up stage — see a paediatrician first. The check-up is a screening tool, not a diagnosis.

In summary

There is one sentence worth remembering about the infant health check-up: "it is not eight visits, it is eight windows." Windows close, and a closed window does not reopen. Dental check-ups are counted separately, and "in-depth assessment recommended" on a result sheet is not a line to skip past. Manage those three things and you will hardly miss a stage.