Figure 1
![Figure 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12891-015-0481-x/MediaObjects/12891_2015_481_Fig1_HTML.gif)
Development process of the SFInX: stages of generation and selection of items, including the SFInX versions and number of items retained at each stage.
Development process of the SFInX: stages of generation and selection of items, including the SFInX versions and number of items retained at each stage.