Abstract:
:When estimating the probability of natural conception from observational data on couples with an unfulfilled child wish, the start of assisted reproductive therapy (ART) is a competing event that cannot be assumed to be independent of natural conception. In clinical practice, interest lies in the probability of natural conception in the absence of ART, as this probability determines the need for therapy. We thus want to estimate the marginal cumulative pregnancy distribution. Without assumptions on the dependence structure between the two competing events, this marginal distribution is not identifiable. We first use inverse probability of censoring weighting assuming that the factors influencing the choice to start ART are known. Then, we parameterize the event distributions for conception and for start of ART and use copulas to account for the dependency between both events. By using these two ways of correcting for the dependent risk of treatment, we obtain a plausible estimation region for the cumulative pregnancy curve and for the prognostic effect of tubal tests.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
van Geloven N,Geskus RB,Mol BW,Zwinderman AHdoi
10.1002/sim.6280subject
Has Abstractpub_date
2014-11-20 00:00:00pages
4671-80issue
26eissn
0277-6715issn
1097-0258journal_volume
33pub_type
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