Abstract:
:A technique is presented which provides guidance on the spacing of follow-up waves in a multiwave study. Only information from the baseline wave is needed, as well as rough parameter estimates for the survival distribution. The computations use the expected Fisher information; a new method for its calculation is given. An analysis of the effects of simplifying assumptions, such as presuming that a distributional parameter is known, shows that gross discrepancies may result. Data from the Massachusetts Health Care Panel Study (MHCPS) are used for a demonstration. The MHCPS example shows that this technique can prevent large inefficiencies in multiwave experimental design.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Chappell Rdoi
10.1002/sim.4780101209subject
Has Abstractpub_date
1991-12-01 00:00:00pages
1945-58issue
12eissn
0277-6715issn
1097-0258journal_volume
10pub_type
杂志文章abstract::Causal inference for non-censored response variables, such as binary or quantitative outcomes, is often based on either (1) direct standardization ('G-formula') or (2) inverse probability of treatment assignment weights ('propensity score'). To do causal inference in survival analysis, one needs to address right-censo...
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pub_type: 临床试验,杂志文章,随机对照试验
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