Figure 3
![Figure 3](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2F1477-7525-2-29/MediaObjects/12955_2004_Article_110_Fig3_HTML.jpg)
The estimates of the item parameters obtained using the cold deck imputation procedure and by treating the missing item responses as if they had never been offered to the individual patients. The horizontal and vertical lines indicate the 95% confidence intervals for these estimates.