As the general election in the UK approaches, experts writing in The BMJ this week question whether the party promises on access to general practice are likely to be achievable.

Tom Cowling and colleagues at Imperial College London say pledges on the GP workforce "are unlikely to be achieved within a parliamentary term" and guarantees of an appointment within 48 hours "may prove unrealistic."

Access to general practice is a prominent issue in national policy debate ahead of the 2015 UK in May - and the two main parties, Conservative and Labour, have both made bold pledges on this topic, write the authors.

For example, the prime minister has declared that everyone in England will be able to see a general practitioner between 8 am and 8 pm, seven days a week, by 2020 if the Conservative Party is re-elected to government.

The government also plans for an extra 5,000 GPs and spending an additional £2bn on the frontline of the English NHS next year (currently there are 40,000 GPs and spending is £115bn). Meanwhile, the Labour Party aims to guarantee a GP appointment within 48 hours, a policy recycled from past Labour governments. Labour also intends to recruit 8,000 more GPs.

But the authors point out that the problem with access "has not been precisely defined; nor has the evidence behind pledges been made clear."

To gauge the problem of access, they analysed data from the GP Patient Survey - a national survey of patients' experiences - and found that in 2013-14, around 90% of attempts to get general practice appointments in England were successful.

The authors also question the aims of increased access, pointing out that although politicians may intend to improve satisfaction with primary care, data suggest patients are often willing to forgo quicker access in favour of other appointment characteristics (such as seeing a particular GP) that are highly valued.

Both parties also hypothesise that their policies will reduce attendances at emergency departments. But the authors argue that, although visits to such services increased from 17.8 million in 2004-05 to 21.8 million in 2013-14, "existing evidence on whether improving access to general practice reduces emergency department visits is inadequate to inform policy."

Politicians' promises of an extra 5,000 to 8,000 GPs are also likely to be challenging to achieve, they add.

They suggest five points of action for policy and research if improvements in access are pursued. These include evaluating the government's extended opening hours pilot scheme, discussing the skill mix in general practice to allow GPs to focus on complex care for the sickest patients, and evaluating new types of appointment, such as telephone and email consultations.

"The public should question the promises of politicians and policies should be independently evaluated before wide implementation," they conclude.

More information: Evidence and rhetoric about access to UK primary care, The BMJ, www.bmj.com/cgi/doi/10.1136/bmj.h1513

Journal information: British Medical Journal (BMJ)