Table 4a.

Characteristics of subjects reporting 0–1 and ≥2 persistent pain conditions

	0~1 pain conditions	≥ 2 pain conditions
	Mean (SD)	Mean (SD)
Age (in years)*	30.6 (11.2)	40.5 (12.1)
Facial Pain duration from onset (months)*	39.6 (78.9)	117.6 (109.7)
Average facial pain intensity (past 6-mon)*	1.7 (2.6)	4.5 (2.5)
Impact due to facial pain (past 6-mon)
Missed usual activities (days)*	2.5 (15.6)	6.1 (16.6)
Reduced efficiency to <50% (days)*	8.8 (48.4)	17.1 (31.4)
Facial pain in the past 1–2 weeks
1. Average intensity*	13.3 (21.9)	38.7 (26.3)
2. Highest intensity*	20.9 (31.6)	54.8 (31.0)
3. Lowest intensity*	4.9 (12.1)	17.1 (19.0)
5. % of wake days with pain*	15.7 (28.6)	55.1 (35.7)
6. Unpleasantness rating*	2.7 (4.4)	8.0 (4.7)
Grade chronic pain scale-facial pain (%)*
GCPS-0	65.1	12.7
GCPS-I	16.9	33.8
GCPS-II	15.3	42.3
GCPS-III	0.8	7.0
GCPS-IV	1.9	4.2

Abbreviations: TMD, temporomandibular disorders; WPT, widespread palpation tenderness; w/o, without; 6-mon, 6 months; GCPS, Grade Chronic Pain Scale.

Note: Number of study subjects included in each group for clinical pain measures:

1. 0–1 pain condition group: range 258–265;
2. ≥2 pain conditions group: range 71–75.

^*P<0.004