Investigation of prospective longitudinal development of such pychological changes after a whiplash trauma

Abstract

Background: Not only physical functions, but also psychological factors are more relevant to the whiplash. One way to reflect whiplash is recorded by Neck Disability Index (NDI). Objectives: The principal research is to investigate the association between NDI scores and the various psychological factors, social activities and working status after an injury. Also gender and age are taken into account. Furthermore, the analysis is carried out after categorizing NDI (NDIc) into two levels by mean. Material: The dataset includes 20 patients and all the information is recorded at week 1, week 6 and week 12 after an accident. Methods: Linear mixed model is fitted for the response of NDI. Marginal models (Generalized Estimating Equations (GEE) and Alternating Logistic Regression (ALR)) and random effect model are fitted for the response NDIc. Results: For the continue response of NDI, it obtains a model with a significant of Tampa Scale of Kinesiophobia (TSK), State- Trait Anxiety Inventory-Situational (STAI-S), State-Trait Anxiety Inventory -Trait (STAI-T), and the significant different evolutions for both male and female group over time. When the model takes Visual Analog Scale (VAS), physical activities (FA) and social activities (SA) into account, there are not only the significant effects by psychological factors, but also VAS, FA and SA. For the binary response of NDIc, there is only a significant effect of TSK. Following, taken FA, SA, VAS into account, there are only a significant effect of VAS and no effects of psychological factors. Discussion and Conclusion: Based on all the models, it implies that psychological factors act the important roles for reflecting the NDI scores. However, when the response is categorized into two levels by mean, the results cannot correctly reflect the NDI.