At 10:01 15/10/05 +0100, Doug Altman wrote (in small part):
>That said, the epidemiological literature is full of such studies, where
>one may certainly wonder what degree of selection went on - both selection
>within the study (eg reporting only a subset of subgroup analyses) and
>across studies (notably non-publication of 'uninteresting findings).
Indeed, but as Ted has pointed out, it's rather difficult to see why either
of those types of selection would result in bias of published findings
towards either left- or right-handedness. If a review/meta-analysis of
published results did seem to suggest a result in one direction or the
other, then I think there would definitely be 'a case to answer'.
It is obviously very easy to dismiss any such findings as 'far
fetched'. However, as for 'plausible explanations', it's not that hard to
believe that handedness might influence the 'laterality' (right or left
breast) of breast cancer - and if there were morbility/mortality
differences between cancers of the right and left breasts (again, far from
impossible, because of anatomical considerations of venous and lymphatic
drainage) that could, I suppose, lead to a relationship between handedness
and morbidity/mortality. If we were talking, say, about cervical cancer, I
would be far less inclined to entertain the possibility of 'plausible
explanations'.
Kind Regards,
John
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