Abstract
Background
Depression, anxiety, catastrophising, and fear-avoidance beliefs are some of the so-called “yellow flags” that predict a poor outcome in back patients. Many surgeons have difficulty assessing yellow flags, perhaps due to the complexity of existing instruments and time constraints during consultations. We developed a brief tool to allow the systematic evaluation of core flags.
Methods
Data from 4 questionnaires (ZUNG depression (N=399); Hospital Anxiety and Depression Scale (Anxiety-subscale) (N=308); Pain Catastrophising (N=766); Fear Avoidance Beliefs (N=736)) were analysed to identify the respective single item that best represented the full scale score. The 4 items formed the “Core Yellow Flags Index” (CYFI). 1'768 patients completed CYFI and a Core Outcome Measures Index (COMI) preoperatively, and COMI 3 and 12mo later (FU).
Results
The individual flag items correlated with their corresponding full-length questionnaires: 0.71 (depression), 0.81 (catastrophising), 0.77 (anxiety), 0.83 (fear avoidance beliefs). Cronbach's α for the 4 items was 0.79. Structural equation modelling revealed that CYFI explained a unique proportion of the variance in COMI at 3 months' FU (β=0.23, p< 0.001) and also at 12 months FU (β=0.20, p< 0.001).
Conclusion
The 4-item CYFI proved to be a simple, practicable tool for routinely assessing key psychological attributes in spine surgery patients; it made a relevant contribution in predicting postoperative outcome. CYFI's items were similar to those in the “STarTBack screening-tool”, used in primary care to predict back pain chronicity, further substantiating its validity. Its wider use may help improve the accuracy of predictive models derived using spine registry data.
No conflicts of interest
No funding obtained
