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I would like to thank Dr Iversen and colleagues for helping to bring
this issue to attention. I am trying to set up a large epidemiological
study on patients with dementia. This uses standard clinical data and and
I will need to apply to the ONS for flagging. I have been grappling with
the issues you describe, particularly that of excluding patients unable to
consent or those without carers (to give assent). Not including such
subjects introduces the possibility of selection bias that in my opinion
may render my results meaningless. Thus the progress of research into
"vulnerable" groups such as patients with dementia may be held back or
cannot be applied to a representative real life population. I am beginning
to make some progress into grappling with the issues and this article has
provided me with some useful pointers.
Competing interests:
None declared
Competing interests:
No competing interests
21 January 2006
Elizabeth L Sampson
MRC Fellow in Health Services Research
Department of Mental Health Sciences Royal Free and University College Medical School, NW3 2PF
Dementia poses similar problems
I would like to thank Dr Iversen and colleagues for helping to bring
this issue to attention. I am trying to set up a large epidemiological
study on patients with dementia. This uses standard clinical data and and
I will need to apply to the ONS for flagging. I have been grappling with
the issues you describe, particularly that of excluding patients unable to
consent or those without carers (to give assent). Not including such
subjects introduces the possibility of selection bias that in my opinion
may render my results meaningless. Thus the progress of research into
"vulnerable" groups such as patients with dementia may be held back or
cannot be applied to a representative real life population. I am beginning
to make some progress into grappling with the issues and this article has
provided me with some useful pointers.
Competing interests:
None declared
Competing interests: No competing interests