None of the five large earlier studies reported results from subgroups of the ICU population [ 3- 7].
The findings from the AHSMOG are difficult to interpret, with higher effects in men in the larger earlier study [ 40] and larger effects in women in the smaller cohort with longer follow-up [ 41].
The study was substantially larger than earlier studies, including information from all patients, including those with short survival.
More recent studies tended to be larger than earlier studies, and there were positive associations between probability of achieving statistically significant results and size of the placebo arm.
Our collaborative approach yielded a sample of 161 patients, which is three times larger than any earlier study on this ICU collective and allowed us to estimate discriminatory performance more robustly than other studies, not only in the overall population but also in important subgroups.
One large and early study suggests females live longer than males, especially virgin females [24].
In an earlier study larger effects were shown for narrow roads with road width below eight meters compared to roads 8 10 m wide [32].
The present study included bi-directional sequencing, and the total number of ESTs is more than 14 times larger than in the earlier study.
In the earlier study of large rural construction projects, the excess risk in this overlap period was also greater than in the construction period as a whole (Kinlen et al, 1995).
The study periods were defined as in an earlier study of large post-war rural construction projects (Kinlen et al, 1995) as follows: (a) the construction period together with the calendar year immediately following, that is, 1940 43, henceforth termed the 'construction period'; (b) the period of greater PM in which construction overlapped with the operation of the ROFs, that is, 1941 42.
