Consultant Gareth Thomas explains which patients are less likely to attend clinics
Hospitals should consider charging patients who fail to arrive for their appointments without notification, the Welsh NHS Confederation has said.
The proposal came as Cardiff and Vale NHS Trust released figures which show over 200 of its outpatients do not attend appointments every day.
The annual cost to the trust is £3m, while across Wales 300,000 patients fail to attend appointments every year.
The trust has started a campaign urging patients to "turn up or phone up".
Matt Temby is a programme manager at Cardiff and Vale in charge of running the campaign.
He said: "Over 200 patients fail to turn up for their appointments every day. That's almost 70,000 a year, which could fill the Millennium Stadium.
"Unfortunately, people missing their hospital appointments cost Cardiff and Vale NHS Trust £3m a year.
"Three million pounds could pay for 95 qualified nurses for a year, or 372 hip replacements a year. That could make a real difference to patients in Cardiff and the Vale of Glamorgan."
We would like people in advance to contact us so that we can use that appointment slot for other patients to be seen rather than it simply lay vacant
Gareth Thomas, consultant physician
Jonathan Davies, policy and public affairs manager for the NHS Confederation, called patients failing to turn up because they forgot or failing to cancel appointments through apathy "unacceptable behaviour".
He said: "The idea of introducing a discretionary charge in these cases is a debate that is worth having as it may well help improve the current situation.
"We know that some NHS organisations in Wales are trialling innovative ways - such as text reminders - to help reduce missed appointments, and we encourage innovation in the use of technology"
Gareth Thomas is a consultant physician at the University Hospital of Wales.
He said it was common for between 10% and 20% of patients not to attend the clinic without letting staff know.
"It's a big issue and has been for many years. In spite of various measures that people have taken over the years, it has remained much around that level.
"It's high particularly for the follow-up patients. It comes out at around 20% and that equates to one-in-five clinics being wasted.
"That knocks on to waiting list issues, and people needing to see us who then can't get in in a timely fashion."
He said people sometimes did forget, or did not prioritise things as they should, and sometimes genuinely had "real, more important issues" cropping up.
"What we are trying to get over is that we would like people in advance if they know that to contact us so that we can use that appointment slot for other patients to be seen rather than it simply lay vacant," he added.
A spokesman for the assembly government said it welcomed the trust's "turn up or phone up" campaign.
"The NHS is working hard to provide greater choice to patients in setting appointments, but patients must play their part too," he said.
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