Table 1.
Study | Mean (SD) hours worked per month | Mean (SD) monthly earnings ($) |
---|---|---|
Bond et al23 | Not known | 127.1 (190) v 71.7 (234)*, P<0.05 |
Drake et al24 | 33.7 (46) v 11.4 (22), P<0.001 | 188.5 (302) v 59.9 (124)†, P=0.001 |
Drake et al25 | 17.9 (31) v 1.5 (6.9), P<0.001 | 111.1 (188) v 111.4 (163)‡, NS but no exact P value reported |
Gervey and Bedell26 | 69.0 v 9.9 (no SD reported), P<0.03 | Not reported |
McFarlane et al27 | Not known | 41.9 v 11.8 (no SD reported)§, P=0.019 (Mann-Whitney) |
Conversion factor at time of writing: *£89.06 v £50.24; †£132.09 v £41.97; ‡£77.85 v £78.06; §£29.36 v £8.27.