Fig. 4
![Fig. 4](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs13195-017-0265-7/MediaObjects/13195_2017_265_Fig4_HTML.gif)
Optimization of CSF collection procedures. Effects of different factors. Results are shown as mean ± 95% confidence intervals for each factor in the analysis. ColTube collection tube, FT freeze/thaw, H high, L low, LoB low binding, PP polypropylene, StorTube storage tube, Vol volume