Table VI.

Data content filter summary

Stage	Grade A	Grade B	Grade C	Σ
1	78	0	0	78
2	16	0	21	37
3	0	0	0	0
Σ	94	0	21	115

Authors applied a wide variety of filters for data content, which are listed in Table IV. For each stage and grade, the number of content filters applied is tabulated. For each author, a filter was counted only once, even if applied repeatedly (e.g., to compute several CVMs).