Missed appointments

02.1The gap between booking and attending

The single most reliable pattern in missed appointments is distance in time. An appointment booked for tomorrow is rarely missed. One booked eleven weeks ahead is missed far more often, because eleven weeks is long enough for circumstances, memory and intention to all change.

This is why the shape of the diary and the miss rate are the same problem. A practice that books everything far ahead has chosen a higher miss rate as a side effect. Shortening the booking horizon for some appointment types is often a bigger lever than anything done in the week of the appointment itself.

02.2What reminders actually do

A reminder does two useful things: it repairs a memory failure, and it gives a person an easy moment to cancel. The second is at least as valuable as the first. An appointment cancelled three days out is capacity; an appointment cancelled by silence is a hole.

Timing matters more than volume. One reminder far enough ahead that the slot can be refilled, and one close enough to the appointment to be acted on, covers most of the ground. Reminders sent so often that they are ignored have converted a useful message into background noise, and there is no way to un-ring that bell quickly.

The wording is part of the mechanism. A reminder that states the day, the time and what to do if the time no longer works is doing its job. A reminder that only confirms is a receipt.

02.3Making cancellation easy on purpose

Practices sometimes make cancelling deliberately awkward, on the theory that friction protects the diary. It does the opposite. Friction does not convert a cancellation into an attendance; it converts it into a silent absence, which is the most expensive outcome available.

The version that works is uncomfortable at first: tell people plainly how to cancel, make it possible without a conversation, and treat an early cancellation as a good outcome rather than a small failure.

02.4Refilling at short notice

A cancellation only becomes capacity if someone can be found to take it. That requires a list — of people who have said they would come sooner if a slot appeared — and a habit of working it. The list is worth keeping short and current. A long stale list is slower to use than an empty one, because every call is a coin toss.

The practical constraint is who does the calling and when. If refilling is nobody's named job, it happens when the desk is quiet, which is exactly when it is least likely to succeed.

02.5Overbooking and its cost

Deliberate overbooking trades one problem for another. It protects against empty slots and produces a waiting room when everyone turns up. Whether that trade is worth making depends on how predictable the miss rate is, and predictability comes from counting.

Practices that overbook without measuring are usually overcorrecting for a bad month they remember vividly. A practice that knows its rate for each appointment type can overbook narrowly, in the one place it is justified, rather than across the whole day.