Areas where people find it easier to make GP appointments, such as online booking systems, see fewer visits to A&E, a study has suggested.
Researchers at Imperial College London said they found no overall link between satisfaction with GP opening hours and the number of visits to A&E in England, but where patients were happier with the ease of making appointments, there were slightly fewer.
They suggested the Government's proposals to extend GP surgery hours would be unlikely to ease the burden on A&E departments, which saw 1.9 million more attendances in 2016/17 than in 2011/12, the equivalent of 5,100 more each day.
The observational study saw the research team compare patients' experiences of GP surgeries with the number of A&E visits in their areas in England from 2011/2012 to 2013/2014.
They examined reports from NHS England's annual GP Patient Survey, and included patients registered to 8,124 GP surgeries.
They measured levels of patient satisfaction using three factors: the ease of making an appointment, opening hours, and overall experience.
They then matched these responses with A&E departments in their area to observe any correlation with the number of visits to A&E.
Satisfaction with surgery opening hours and overall patient experience seemed to have no impact on A&E visit rates in their geographical area
The authors measured satisfaction with hours without linking them to daytime, weekday or evening and weekend appointment availability.
They suggested that although weekend and evening appointments are convenient for healthy, working-aged adults, those who are likely to need medical attention more urgently are older people or those who are chronically ill and not currently working full-time.
Senior author Professor Azeem Majeed, from Imperial College London's School of Public Health, said: "The Government must find alternative ways to handle current pressures on A&E departments.
"This could include, for example, improving access to GP appointments during normal opening hours rather than spending scarce NHS resources on extended opening schemes."
His colleague and lead author Dr Thomas Cowling said: "It makes sense to think that extending GP hours will ease the burden on other NHS services, but our study suggests this might not be the case with A&E."
The study is published in the journal BMJ Quality & Safety.