1.   Lower oesophageal sphincter pressure was measured with the rapid pull through technique.

2.   Lower oesophageal sphincter pressure was measured as the mean from nine rapid pull through readings.

3.   The pressure in and length of the lower oesophageal sphincter were assessed with rapid pull through technique.

4.   Mean rapid pull through pressure was calculated as the average of eight separate pressure values measured from the gastric baseline to the peak of the pressure rise.