Table 6: Pearson correlation between wait time for surgery and differences in outcome from immediately preoperatively to 6, 12 and 24 months after surgery
Outcome measure*Time point; r
6 mo12 mo24 mo
SF-36 PC summary score-0.0790.0630.067
SF-36 MC summary score-0.133-0.224‡-0.115
ODI score0.223‡0.205†0.064
ZCQ score0.200†0.0930.156
Back pain score0.0770.0790.102
Leg pain score0.221‡0.1600.054

Note: MC = mental component, ODI = Oswestry Disability Index, PC = physical component, SF-36 = 36-item Short-Form Health Survey, ZCQ = symptom severity scale of the Zurich Claudication Questionnaire.

*Adjusted for baseline score, age, surgeon, duration of symptoms and surgery type.

p < 0.05.

p < 0.01.