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Finally , in some situations ( albeit very limited ones ) , military tribunals may indeed be preferable to civilian courts . Though both extreme concordant - and discordant - relative pair comparisons can have high statistical power ( 80 ) , the former may often be preferable for studies of survival outcomes , even if DNA from both members of extreme discordant pairs were available : Secular changes in causes of death and morbidity can confound interpretation of findings from siblings who vary greatly in the ages at which an event occurs .