Interobserver Reliability of Tongue Diagnosis Using Traditional Korean Medicine for Stroke Patients

Abstract

Observation of the tongue, also known as tongue diagnosis, is an important procedure in diagnosis by inspection in Traditional Korean medicine (TKM). We investigated the reliability of TKM tongue diagnosis in stroke patients by evaluating interobserver reliability regarding tongue indicators as part of the project named the Fundamental Study for the Standardization and Objectification of Pattern Identification in TKM for Stroke (SOPI-Stroke). A total of 658 patients with stroke admitted to 9 oriental medical university hospitals participated. Each patient was independently seen by two experts from the same department for an examination of the status of the tongue. Interobserver agreement about subjects regarding pattern identification with the same opinion between the raters (n = 451) was generally high, ranging from “moderate” to “excellent”. Interobserver agreement was nearly perfect for certain signs of special tongue appearance (mirror, spotted, and bluish purple), poor for one of the tongue colors (pale) and moderate for others. Clinicians displayed measurable agreement regarding tongue indicators via both observation and pattern identification consistency. However, interobserver reliability regarding tongue color and fur quality was relatively low. Therefore, it is necessary to improve objectivity and reproducibility of tongue diagnosis through the development of detail-oriented criteria and enhanced training of clinicians.

Appropriate Statistics for Determining Chance-Removed Interpractitioner Agreement

“…Since many choices are available to express the disease state of a patient, exact phonetic agreement between practitioners is very unlikely and this is required if there is to be agreement between raters. It seems that to overcome this difficulty, strategies of investigating single disease states and generally restricting practitioners to textbook decreed diagnostic options [1][2][3][4][5][6][7][8][9][10][11] or investigating single diagnostic factors such as tongue or pulse diagnosis 1,12 have been adopted. This approach has the effect of drastically reducing the number of choices given to raters, thereby causing the level of agreement to be inflated compared with that expected with essentially unrestricted diagnostic options.…”

“…The AC1 statistic, although first published in 2002, 24 is only just being adopted as a statistic for general inter-rater agreement evaluations. 7,8,25 While there are other competing statistics, 26 including the recently developed PABAK 19 (which can only be used for two raters), Gwet's AC1 seems to be the best option, as it apparently addresses the free marginal data issue. It is important to note that the AC1 statistic is actually a form of Kappa statistic, with a superior approach to the estimate of agreement by chance that accommodates the assessment of free marginal data.…”

Availability of Tongue Diagnosis System for Assessing Tongue Coating Thickness in Patients with Functional Dyspepsia

“…Tongue diagnosis is an important procedure in TKM, but conventional methods are limited by various external factors [4]. In an attempt to overcome these limitations, different types of TDSs have been recently developed [5].…”

“…In particular, tongue-coating thickness (TCT) is considered to reflect the progression of a pathological condition [3]. A conventional method used in tongue diagnosis involves direct examination of a protruded tongue by a practitioner, so the result is not only affected by his or her subjectivity but also by environmental factors such as light [4]. Moreover, the available diagnostic criteria are insufficient and vague.…”

Jivha Pariksha - One of the Diagnostic Tools in Ayurveda: A Review

“…The processes of image capturing and storage are hardware resources, while those of color correction and tongue segmentation are imagepreprocessing steps in tongue diagnosis. Image analysis process comprises classification of the tongue according to selected diagnostic parameters [11][12][13][14] .…”