Origin of and therapeutic approach to cardiac syndrome X: Results of the proton pump inhibitor therapy for angina-like lingering pain trial (PITFALL trial)

Table 2 Definitions of ranks in visual analogue scale (characteristics of symptoms)

Grade	Frequency	Duration	Intensity
10	Permanent	Permanent
9	Several times daily	Almost whole day
8	Daily	More than 6 h
7	Almost daily	More than 2 h
6	Several times weekly	About 1 h	Grading by patients on a scale from 0 to 10
5	Up to 3 times weekly	10-30 min
4	Once weekly	5-10 min
3	Several times in 1 mo	1-5 min
2	Up to 3 times in 1 mo	Less than 1 min
1	Once per month	A few seconds
0	Never or very seldom	Never

Patients were asked for symptoms and were helped to grade the frequency, duration and intensity using the characteristics below.