Fig. 5
![Fig. 5](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40035-020-00228-9/MediaObjects/40035_2020_228_Fig5_HTML.png)
Forest plot showing associations of serum ferritin (a) and creatine kinase (b) levels with the overall survival in ALS patients. Pooled hazard ratios (HR) suggest significantly reduced survival in ALS patients with elevated serum ferritin, whereas creatine kinase levels did not play a significant role in the survival of ALS patients. Ratios and the corresponding 95% confidence intervals of studies are indicated by short solid lines. The averaged ratios and 95% confidence intervals are indicated by diamonds