OBJECTIVETo establish corresponding set pair analysis mathematic model using the clinical symptoms of blood-heat type psoriasis vulgaris (BHTPV), thus guiding the clinical accuracy of clinical syndrome typing.

METHODSRecruited were 202 BHTPV with complete data after they were treated by yang subduing blood cooling method. Their clinical symptoms and signs were systematically collected. Using set pair analysis method, the therapeutic results of cured and markedly effective were recruited as the same portion, of effective as the different portion, and of ineffective as the contrary portion. The U value of each syndrome factor was calculated according to the formula. The correlation factor of syndrome typing of BHTPV was screened. The syndrome typing model of BHTPV was established according to the correlation factor.

RESULTSThe main factors of BHTPV included the scale integral > 2.04, the erythema integral > 2.34, age > 50 years old, the area integral > 2.07, dry mouth, slippery pulse, yellowish fur, soggy pulse, dry and hard stool. The secondary factors included less sweat, insomnia, frequent pulse, any infiltration, erythra of any area, red tongue, depression, the disease course ranging 1-360 months, age ranging 16-50 years old, string-tight pulse, thin fur, the area integral ranging 0-2.07, white fur, purplish tongue, the scale integral ranging 0+ -2.04, and feeble pulse. The third factors included the erythema integral ranging 0-2.34 and pale red tongue. The set pair analytical model of BHT-PV was as follows: U = sigma An/N + sigma B(m)i/M + sigma C(p)j/P.

CONCLUSIONSU blood-heat syndrome > or = 0.75 could be judged as blood-heat syndrome. Satisfactory efficacy could be achieved by blood cooling method. For patients with U blood-heat syndrome < 0.75, no satisfactory efficacy could be achieved by blood cooling method alone since they were accompanied with other syndrome types.