Table 1.

Psychological factor and health-related quality of life among different overlapping conditions

	N	Anxiety	Depression	MCS	PCS	SF-36
IBS only	150	8.31 ± 3.09	6.15 ± 3.62	61.47 ± 21.38	63.73 ± 16.22	62.60 ± 17.16
Two overlapping conditions	95	8.73 ± 3.66	6.69 ± 4.08	55.41 ± 23.93a	57.67 ± 18.09a	56.54 ± 19.56a
Three overlapping conditions	59	8.71 ± 3.40	7.17 ± 3.33	52.09 ± 20.68a	54.97 ± 17.32a	53.53 ± 17.58a
Four overlapping conditions	15	7.60 ± 3.80	6.40 ± 3.87	47.91 ± 24.94a	49.27 ± 21.23a	48.59 ± 21.84a

^aCompared with IBS only, P < 0.05

Abbreviations: IBS irritable bowel syndrome, MCS mental component summary, PCS physical component summary, SF-36, 36-item Short-Form Health Survey