Tongue and mouth imagery questionnaire (TMIQ) for assessing motor imagery vividness of the temporomandibular region: A reliability and validity case‐control study

BACKGROUND: To date, no validated assessment of motor imagery (MI) ability with temporomandibular disorders (TMD) exists preventing identification of good imagers and appropriate MI use during TMD rehabilitation. OBJECTIVE: To assess the reliability and construct validity of the previously developed Tongue and Mouth Imagery Questionnaire (TMIQ) compared with the gold‐standard Kinaesthetic and Visual Imagery Questionnaire (KVIQ‐10). METHODS: Both KVIQ‐10 and TMIQ assess MI ability using vividness (i.e. clarity/brightness for visual MI, (V)MI; or intensity for kinesthetic MI, (K)MI) of MI using a 5‐point Likert scale (1: no image/sensation, 5: clear/intense image/sensation). The KVIQ‐10 was administered once (test) and the TMIQ twice (test–retest) to heathy participants and patients with TMD. Questionnaire validity was investigated using concurrent validity (Pearson correlation and paired t test); TMIQ‐test–retest reliability (intraclass correlation coefficients, ICCs); internal consistency (Cronbach ⍺) and the factorial structure (principal factor extraction). RESULTS: A total of 94 participants were included (n = 47 per group). The mean vividness scores of the KVIQ‐10 and the TMIQ were significantly correlated, and not significantly different for both groups indicating concurrent validity. ICCs in the control group (range: 0.82‐0.90), and in the TMD group (range: 0.75‐0.82) indicated good reproducibility. The Cronbach ⍺ values were all above 0.94, indicating excellent reliability. Two factors were extracted corresponding to (V)MI and (K)MI, and explained 66% of total variance. CONCLUSION: The TMIQ is a valid and reproducible MI questionnaire showing excellent internal consistency and, therefore, can be used to assess imagined movements of the TM region in healthy individuals and patients with TMD.