They found a twofold difference in prevalence between the extremes.
The dangers in letting spirit testimonies transit the space of experiment were twofold.
The main conclusions of this paper, which have been stressed in the preceding discussion, are twofold.
The goal of the present study with clinical populations was twofold.
Our goal in this work has been twofold.
In general terms, this, it is hoped, is twofold.
The aims of this aspect of the study were twofold.
The costs of providing this guarantee are twofold.
