Around one in 20 calls made to NHS 111 led to unnecessary emergency department attendances within 24 hours, despite being advised to seek alternative care.
The results suggest that women and those calling with regard to a child under the age of five were more likely to go to emergency care in these circumstances.
However, those who had managed to speak with a clinician appeared less likely to do so.
Researchers analysed more than 16.5 million calls made to the medical advice helpline from across all regions of England between March 2015 and October 2017.
These avoidable attendances could be predicted, to a certain extent, based on call characteristics. It may be possible to use this information to help 111 call handlers identify which callers are at higher risk of these attendancesResearchers
Of the 779 in every 1,000 callers told not to seek emergency care, 83 decided to anyway, within 24 hours of their initial call. The data indicates that 42 of these could have been dealt with elsewhere.
As well as access to advice from a clinician, researchers found that being a patient at a general practice where it was relatively easy to get an appointment, reduced the chance of a person ignoring recommendations not to go to hospital.
“These avoidable attendances could be predicted, to a certain extent, based on call characteristics,” scientists said in their paper, published in the BMJ Open journal.
“It may be possible to use this information to help 111 call handlers identify which callers are at higher risk of these attendances.”
The findings come at a crucial time for the free NHS 111 helpline, which has experienced a surge in demand amid coronavirus concerns.
Recent figures show 111 received an extra 120,000 calls in the first week of March, up more than a third compared with the same time last year.
Between February 27 and March 5 this year, NHS 111 answered 389,779 calls.