Assessment and further development of RDC/TMD Axis II biobehavioural instruments: a research programme progress report

Abstract

A symposium was held in Toronto, 2008, in which research progress regarding the biobehavioural dimension of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) was presented. An extended workshop was held in April 2009 in which further recommendations were made from an expert panel, using the 2008 symposium material as a base. This paper is a summary of the 2008 symposium proceedings with elaborations based on further developments. Seven studies were conducted between 2001 and 2008, in which the following were investigated: (i) basic properties of Axis II instruments, (ii) reliability and criterion validity of Axis II instruments, (iii) expansion of predictors, (iv) metric equivalence of the depression and non-specific physical symptoms subscales in the RDC/TMD, (v) laboratory investigation of oral behaviours, (vi) field data collection of oral behaviours, and (vii) functional limitation of the jaw. Methods and results for each of these studies are described. Based on the results of these studies that have been published, as well as the direction of interim results from the few studies that await completion and publication, the biobehavioural domain of the RDC/TMD, as published in 1992, is reliable and valid. These results also provide strong evidence supporting the future growth of the biobehavioural domain as the RDC/TMD matures into subsequent protocols for both clinical and research applications.

© 2010 Blackwell Publishing Ltd.

Figures

Figure 1

Flow of participants from recruitment sources and across studies. Study site for the different stages of the Axis II studies are also indicated. Heavy lines with arrows signify pathway for the core Validation Project by which participants were recruited for the main Axis II study (Study 1) and the primary studies for examining specific psychometric properties (Studies 2a, 2b, 2c) or utilizing additional data (Study 3). Solid thin lines with arrows represent recruitment of psychologically symptomatic patients or TMD patients (Study 4), TMD clinic patients (Studies 5, 6, 7), or community cases (optional for Studies 5 or 6; mandatory for Study 7). Dashed lines with arrows signify recruitment of healthy controls into Studies 5, 6, and 7. Study 1 and Study 3 were conducted at all three study sites: University at Buffalo (UB), University of Minnesota, and University of Washington (UW). Study 2 was conducted at only UB and UW, and Studies 4, 5, 6, and 7 were conducted at only UB.

Figure 2

Plot from profile analysis of log EMG activity from each muscle by task demonstrating significant differences across tasks based on 3-dimensional variate formed from measured electromyographic (EMG) activity of masseter, temporalis, and suprahyoid muscle units (Wilks lambda=.07034, F (27, 20)=9.7906, p=.00000). Experimental groups (cases, controls) are collapsed together. Y-axis refers to natural log-transformed values of EMG activity in microvolts; vertical bars denote 0.95 confidence intervals. See text for further description of each task.