類風濕性關節炎（RA） 在中醫是屬「痹證」範疇，本病常虛實相兼，寒熱錯雜，痰瘀互結，辨證分型相當分歧，本研究在風濕科特別門診篩選符合現代醫學診斷標準的79 位RA 患者，進行「望聞問切，四診合參」之傳統中醫辨證，並綜合分析，依據中醫學理的疾病辨證編碼系統進行編碼，嘗試建立其中醫臨床流行病學資料庫，然後用集群分析法進行統計分析。結果可見「濕熱」、「氣陰兩虛夾濕熱」、「陰虛有熱」及「虛證」等四種主要證型，病機以濕熱及虛證最為重要。本研究提供了虛實寒熱夾雜的辨證分型模式，並發現本項研究RA 患者之主要證型表現以熱證較多，與許氏文獻報告寒證較多之狀況不盡相同。Rheumatoid arthritis (RA) is related to the category of “Bi” in traditional Chinese medicine (TCM). The clinical patterns are usually complicated with vacuity, repletion, cold, heat, phlegm, or blood stasis. The purpose of our study was to set up a clinical epidemiological database for RA according to the aspect of pattern-identification according to TCM. Seventy-nine RA patients who fulfilled the criteria were recruited via the rheumatology out-patient clinic. They were examined by experienced physicians. A TCM pattern-identification coding system was applied to generated codes for the different etiologies, locations, mechanisms, and consequences of RA. The data set was managed using cluster analysis. Our study population included four predominant subgroups, i.e., vacuity, damp heat, yin vacuity with heat, and Qi and yin vacuity with damp heat. This limited database showed the pattern distribution of RA characterized predominantly by heat, which is different from the predominantly cold patterns of RA found in a literature review of reports in Mainland China.