Iderberg H, et al. - Experts ascertained the predictive factors for the outcome of surgery for lumbar spinal stenosis in Sweden. The relevance of adding socioeconomic factors to clinical factors for analysis of patient-reported outcomes was highlighted in the findings, nonetheless, they noted an unknown impact of the causal pathway of most predictors. For predicting outcome of surgery for LSS, a foundation of case mix algorithms is presented in the findings. Previous surgery, having had back pain more than 2 years, having comorbidities, being a smoker, being on social welfare and being unemployed were some factors predicting a worse outcome.