Table 2.

Scores assessing the type of stool and the severity of irritable bowel syndrome (IBS) symptoms based on the information obtained by telephone interviewers after transformation for statistical analyses.

Variable	Primary Score	Transformed Score
The type of stool	Bristol stool scale (points 1–7)	0—constipation if primary scale = 1 or 2 1—normal stool if primary scale = 3 or 4 2—diarrhea if primary scale = 5 or 6 or 7
The severity of pain, flatulence, stool pressure	5-point Likert scale	0—no or weak if primary scale = 0 or 1 1—intermediate if primary scale = 2 2—strong or very strong if primary scale = 3 or 4