Clinical diagnosis of acute appendicitis can be difficult and yet it is the most common surgical abdominal emergency. There is no specific clinical diagnostic test for appendicitis, and removing a healthy appendix -- which happens often -- is best avoided. Similarly, missing appendicitis when it's present can be dangerous.

Although some doctors have routinely asked about pain travelling over speed bumps, this practice was not previously evidence-based.

Researchers from the University of Oxford and Stoke Mandeville Hospital therefore carried out a study on 101 patients who were referred to hospital for suspected appendicitis. Testing took place in 2012 and patients were between 17 and 76 years of age.

Patients were classed as "speed bump positive" if they had a worsening of pain whilst travelling over speed bumps or "speed bump negative" if their pain stayed the same, if they were unsure, or if their pain improved. All participants were questioned within 24 hours of their journey to hospital.

Sixty-four patients had travelled over speed bumps on their way to hospital. 54 of these (84%) were "speed bump positive." 34 of the 64 had a confirmed diagnosis of acute appendicitis of which 33 (97%) had worsened pain over speed bumps.

Seven patients who were "speed bump positive" did not have appendicitis but did have other significant problems such as ruptured ovarian cyst or diverticulitis (bulging sacs or pouches most commonly found in the large intestine).

Clinical questioning about pain over speed bumps also compared favourably with the well known signs of appendicitis.

The researchers conclude that an increase in pain over speed bumps is associated with an increased likelihood of acute appendicitis. They add that although being "speed bump positive" does not guarantee a diagnosis of appendicitis, the study does suggest that it should form a routine part of assessment of patients with possible appendicitis.

Dr Helen Ashdown of the Department of Primary Care Health Sciences at the University of Oxford said: "It may sound odd, but asking patients whether their pain worsened going over speed bumps on their way in to hospital could help doctors in a diagnosis. It turns out to be as good as many other ways of assessing people with suspected appendicitis."