Linked Life Data

1963134

Source:http://linkedlifedata.com/resource/pubmed/id/1963134

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1991-3-29
pubmed:abstractText
In clinical trials carried out to assess the efficacy of different drugs in reducing the frequency of occlusion after coronary artery bypass, the ratio of the number of patients with at least one occluded anastomosis to the number of patients catheterized up to a given day is a widely adopted statistic. In the early evaluation (at 1 or 2 months after surgery), this is affected by the distribution of timing of angiography and it tends to underestimate the cumulative probability of occlusion because patients whose anastomoses are all patent at angiography and occlude between angiography and the day at which the ratio is estimated do not contribute their events to the numerator of the ratio. One may sensibly assume that this underestimate does not affect the evaluation of the efficacy of treatments tested "within" the trial. In contrast, since the distributions of the timing of angiography vary substantially from trial to trial, it can make comparisons "between" trials unclear and possibly biased. The aim of this article is to suggest an alternative approach of statistical analysis in terms of logistic regression. By modeling the dichotomous response given by each patient in function of time at angiography, type of treatment, and other possible covariates, asymptotically unbiased estimates of the cumulative probability of occlusion are attained. Furthermore, the pertinent hazard function can be estimated. The main features of the model are discussed and the results obtained by fitting early data collected in the Studio Indobufen Nel Bypass Aortocoronarico (SINBA) are given.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0197-2456
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
420-32
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
A linear model suitable for assessing graft patency in controlled clinical trials. SINBA Group.
pubmed:affiliation
Istituto di Statistica Medica e Biometria, Università di Milano, Italy.
pubmed:publicationType
Journal Article, Clinical Trial, Randomized Controlled Trial, Multicenter Study