Table 1
Study sample described by report period and level of harm
Reporting period
Group
Group size, N
Level of Harm
Total
None
Low
Moderate
April 2005–2009
1
18 039
2162
846
631
3639
2010–2011
2
12 660
2237
894
770
3901
2012–September 2013
3
11 198
2292
1721
947
4960
6691
3461
2348
12 500