A documented problem.
A solvable one.
Missed appointments cost health systems hundreds of millions every year. The research on what prevents them is clear. This page sets out the numbers — and what they mean.
525,000 missed appointments a year. €129 each. None of it inevitable.
Ireland's health system loses more than €67 million every year to missed outpatient appointments — roughly 525,000 in total, or around 10,000 every week. The HSE formally values each missed appointment at €129, based on the clinical time and administrative resource it consumes.
DNA rates — "did not attend" — vary significantly across the system. At some hospitals they exceed 19–20%. That means one in five booked slots produces no clinical output: no patient seen, no list reduced, no waiting time recovered.
Meanwhile, more than 700,000 people are on acute hospital waiting lists. Every wasted slot is a slot that someone on that list needed. The connection between missed appointments and waiting list length is direct and measurable — which is why the Department of Health and the HSE have both begun treating this as a priority intervention target.
The HSE Outpatient DNA Strategy (June 2023) mandates SMS reminders as part of standard outpatient practice. Reducing missed appointments is not a discretionary goal — it is now a stated operational requirement across the system.
8 million missed appointments. £1.2 billion a year. One of the most solvable problems in the NHS.
The NHS missed appointment problem is larger in absolute terms than Ireland's — but the underlying dynamics are identical. Patients forget. Life intervenes. They don't show up. And the system absorbs the cost silently, appointment by appointment, trust by trust.
What distinguishes the UK evidence base is the quality of intervention research. Multiple NHS trusts have run controlled experiments on reminder timing, message content, and channel selection. The findings are consistent: well-designed, behaviourally informed reminders reduce DNA rates by up to 30% — at a marginal cost that makes the intervention one of the highest-returning in the NHS toolkit.
One trust reduced its DNA rate from 10% to 4% by changing nothing except when its reminders were sent. No new software. No change to booking processes. Just the right message at the right moment.
The NHS Long Term Plan identifies outpatient transformation as a priority. Reducing unnecessary attendances and improving the efficiency of those that do happen — including by ensuring booked appointments are actually kept — is central to that agenda. Diarybook is built to deliver exactly that.
Reminders work. The details determine how well.
The evidence on missed appointment reduction is extensive and consistent. What separates good interventions from great ones is timing, channel, and message design — the three variables Diarybook is built to optimise.
Diarybook is already doing this work. Configurable reminder timing — per clinic, department, and service provider — is a core feature of the platform, not an add-on. The evidence on what works is built into how Diarybook is designed.