Development and psychometric testing of the Japanese version of the Fremantle neck awareness questionnaire: A cross-sectional study

Purpose: Contemporary theories of pain suggest that how the body is perceived is central to the emergence of pain. The Fremantle Back Awareness Questionnaire (FreBAQ) was developed to assess body-perception specific to the back in people with chronic low back pain. However, there is no comprehensive measure to quantify self-perception of the painful area in Japanese people with neck pain. This study aimed to develop a Japanese version of a self-perception questionnaire specific to the neck and evaluate the validity and reliability of the scale using Rasch analysis. Materials and Methods: The Fremantle Neck Awareness Questionnaire (FreNAQ-J) was developed by modifying the FreBAQ-J. One hundred people with chronic neck pain and fifty-six matched healthy controls completed the questionnaire. Rasch analysis was used to evaluate targeting, category order, unidimensionality, person fit, internal consistency, differential item functioning, and differential test functioning in the neck pain population. Validity was investigated by examining the relationship between the FreNAQ-J and clinical status. Results: People with chronic neck pain endorsed FreNAQ-J items with greater frequency than healthy controls. FreNAQ-J did not reject the null hypothesis of fitting the Rasch model, had acceptable internal consistency and good test–retest reliability. Summed FreNAQ-J scores were significantly correlated with pain intensity, disability, pain-related catastrophizing and fear of movement. Conclusion: The individual items of the FreNAQ-J can be validly summed to provide a score of self-perception. The FreNAQ-J is the first scale developed for comprehensively evaluating disturbed body perception in Japanese patients with chronic neck pain