Despite 'changes in practice and development in technology' between 2003 and 2019, the study found that little had changed in rates of missed appointments.
Around 7.2m GP appointments are missed annually, the study found - costing a potential £216m a year - and research papers reviewed for the latest study showed between 5% and 12% of appointments were missed, broadly in line with a range uncovered by a similar review nearly two decades earlier.
Reasons for patients missing appointments were largely linked to their ability to access the service - including childcare, work issues, transport or weather difficulties.
The research, published in the BJGP, identified 'particular groups who are more likely to miss appointments', including patients 'with a mental health diagnosis, those with multiple health conditions, those in ethnic minority groups, and patients attending practices in areas of high deprivation'.
Lead author Dr Jo Parsons of Warwick Medical School said: 'The reasons people miss appointments are really useful when practices look not only at missed appointments, but their whole access systems, which the pandemic is forcing general practices to do at the moment to accommodate the need for social distancing.
'The advice we would give is to look at the person behind the missed appointment. Their reasons for missing are often genuine personal reasons. These people may be vulnerable, under pressure and in groups that are already marginalised.'
Senior author Dr Helen Atherton of Warwick Medical School said: 'GPs are already at huge capacity and maximum workload, but there’s also a patient impact as well. All those patients that are not turning up for their appointments are potentially not having their needs met, their health conditions are not being resolved or treatments delayed. Potentially, there’s a significant potential impact for the NHS again with delayed diagnoses.'
Missed GP appointments
Patients simply forgetting was also a factor cited often as a reason for missed appointments. Dr Parsons added: 'A lot of practices have implemented strategies to try and increase adherence to appointments, through things like text message reminders, appointment cards or e-mail reminders.
'The problem is still there so these are obviously not completely successful. One of the difficulties is that these are not standard and every practice has its own way of working. But it’s also not been front and centre in terms of policy or strategy.'
GPonline has reported previously on the link between missed appointments and booking in advance - with even appointments booked one day ahead three times as likely to be missed as one booked on the day. Analysis of data from NHS Digital suggests that the further ahead patients book, the more likely appointments are to be missed.
Researchers behind the latest study said GP practices should use it to carry out their own reviews of access to services, and to ensure that marginalised or vulnerable groups were not disadvantaged or excluded - a factor they said was more important than ever in the wake of the COVID-19 pandemic.