Linked Life Data

18759834

Source:http://linkedlifedata.com/resource/pubmed/id/18759834

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2009-6-23
pubmed:abstractText
SUMMARY: In many studies, the aim is to learn about the direct exposure effect, that is, the effect not mediated through an intermediate variable. For example, in circulation disease studies it may be of interest to assess whether a suitable level of physical activity can prevent disease, even if it fails to prevent obesity. It is well known that stratification on the intermediate may introduce a so-called posttreatment selection bias. To handle this problem, we use the framework of principal stratification (Frangakis and Rubin, 2002, Biometrics 58, 21-29) to define a causally relevant estimand--the principal stratum direct effect (PSDE). The PSDE is not identified in our setting. We propose a method of sensitivity analysis that yields a range of plausible values for the causal estimand. We compare our work to similar methods proposed in the literature for handling the related problem of "truncation by death."
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1541-0420
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
65
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
514-20
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Sensitivity analysis for principal stratum direct effects, with an application to a study of physical activity and coronary heart disease.
pubmed:affiliation
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. arvid.sjolander@meb.ki.se
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't