Identifying Chinese Medicine Patterns of Tension-Type Headache and Understanding Its Subgroups

Table 22

Results of the cluster analysis.

Clusters	Factors (PCA mean score)
	CMHQ part 1 factors	CMHQ part 2 factors	CMHQ part 3 factors
Cluster 1: ascendant hyperactivity of liver yang	(i) 1.3F4TightHeadache (0.68)	(i) 2.1F4NoFood&Drink (0.69)	(i) 3.1F9LightSound (0.61)
	(ii) 1.3F1RhythmHeadache (0.53)	(ii) 2.1F6MuscularStrain (0.42)
	(iii) 1.1F1CentralHead (0.51)
Cluster 2: dual Qi and blood deficiency	(i) 1.6F2BothEnd (0.72)	(i) 2.2F2PhysicalStimulation (0.65)	(i) 3.1F14SpleenDeficienyOfBowel (0.71)
	(ii) 1.1F3LateralHead (0.66)	(ii) 2.1F3WeatherChange (0.55)	(ii) 3.1F12BloodDeficiency (0.49)
	(iii) 1.6F3AllDay (0.65)	(iii) 2.2F3EatingRelated (0.44)
	(iv) 1.3F1RhythmHeadache (0.56)	(iv) 2.1F4NoFood&Drink (0.42)
	(v) 1.1F1CentralHead (0.51)
Cluster 3: liver depression forming fire	(i) 1.1F2WholeHead (0.66)	(i) 2.1F1Mental (0.42)	(i) 3.1F5LiverStomachFire (0.51)
Cluster 4: nonspecific cluster	(ii) 1.3F2ExplosiveNotDull (0.29)	(ii) 2.1F8WindDamp (0.08)	(ii) 3.1F4PoorDigestion (0.07)
	(iii) 1.3F3SharpHeadache (0.04)		(iii) 3.1F10TemperatureSensitivity (0.09)
			(iv) 3.1F11Constipation (0.04)

: this table reports the results of the TwoStep cluster analyses. Computed from the TwoStep cluster algorithm, mean scores of extracted factors that exceeded value 0.4 are listed for clusters 1, 2, and 3. The cutoff of 0.4 was determined as those clusters being considered to be clinically relevant.