Table 4.

Predictive validity of the patient satisfaction survey

Item	Total satisfaction score,a median				p valueb
	Accept	Refuse	Responder	Nonresponder
Likely to accept vs. refuse future colonoscopy	75	150			<0.0001
Responder vs. nonresponder (Aronchick scale)			75	100	0.7984
Responder vs. nonresponder (Ottawa scale)			75	100	0.4358

^aSum of items 1–4. Survey items 1, 3, and 4 had five-point scales (very easy, easy, tolerable, difficult, very difficult; or excellent, good, fair/tolerable, poor, bad) and were assigned scores from 0–4, with 0 representing most favorable (e.g. very easy or excellent) and 4 representing least favorable (e.g. very difficult or bad). Item 2 (“Were you able to consume the entire preparation as instructed?”) was coded as 0 for yes and 1 for no. Raw scores of each of the four items were transformed to a range of 0–100 (corresponding to 0–4 on the original five-point scale or 0–1 if yes/no) and summed up to a total score, yielding a total score range between 0 and 400, with lower scores indicating higher satisfaction

^bBased on the Wilcoxon rank sum test