Assessing the diagnostic accuracy of the Questionnaire for Sasang Constitutional Classification II (QSCC II): A systematic review

IntroductionSasang constitutional medicine (SCM) is a traditional Korean medicine, in that individuals are classified into one of four types of Sasang constitution (SC). The Questionnaire for Sasang Constitutional Classification II (QSCC II) is commonly used for diagnosing SC type. However, the accuracy rate of the QSCC II is inconsistent. We conducted a systematic review and meta-analysis to assess the diagnostic performance of the QSCC II.Materials and methodsA literature search was performed to identify studies that validated the QSCC II. The methodological quality of the studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool. A bivariate analysis for diagnostic meta-analysis was used to estimate summary sensitivity and specificity for each SC type. The area under the curve (AUC) and Q* were also estimated. Heterogeneity among studies was evaluated through Higgins I-square (I2).ResultsFour studies comprising 1485 participants were included in our review. The QSCC II showed lower diagnostic accuracy for SY type (AUC = 0.7192, Q* = 0.6683) than for the other types (TE type: AUC = 0.8061, Q* = 0.7412, SE type: AUC = 0.8107, Q* = 0.7453). However, strong heterogeneity was identified in all analyses (I2 = 81.5-91.5). The sensitivity analysis excluding another article with the revised QSCC II showed that sensitivity for TE and SE type decreased slightly and sensitivity for SY type increased.ConclusionsThis systematic review shows that the diagnostic accuracy of QSCC II is moderate and could be used to assist practitioners of Sasang constitutional medicine (SCM). However, the total number of included studies was too small to draw firm conclusions and further subsequent primary studies are required.