Spring term seminars 2011
Ives Ntambwe (WMS)
Sample size re-estimation in clinical trials with multiple
endpoints
The choice of an appropriate sample size is a main concern
in the design of any clinical trial. In the planning stage of a
trial one is often quite uncertain about the sizes of
parameters or assumptions needed for sample size
calculations. The idea of this project is to explore the use of
designs that allow checking of these assumptions and
adjustment of the sample size if necessary.
Tuesday 25
January
12:30 13:30
(Room B026)
Wittes and Brittain (1990) proposed use of designs with
sample size re-estimation, also called designs with internal
pilot study (IPS) which look at assumption regarding the
nuisance parameters at an interim analysis.
Multiple endpoints are not uncommon in clinical research.
One example is the use of a test battery in schizophrenia.
The analysis is complicated in the presence of multiple
endpoints and special techniques are needed to control the
Type I error rate because hypotheses are tested for various
endpoints.
This project aims to bring together the concept of designs
with sample size re-estimation and the methodology for
dealing with multiple endpoints. This will provide an
extension of the current methodology for single endpoint
sample size re-estimation to the multiple outcomes setting.
Chris Roberts (University of Manchester)
The Analysis of Non-Pharmacological Treatment Trials
with Partial Nesting and Multiple Therapists per Patient
Tuesday 15
February
12:30 13:30
(Room A011)
In trials of physical and talking therapies nesting of patients
within care-provider can have design and analysis
implications analogous to cluster randomized trials. There
can nevertheless be additional complexity due to
heterogeneity in the pattern of clustering including partial
nesting. In some trials, a patient may receives a therapy
from multiple care-providers, so that the data structure is no
longer strictly hierarchical.
This talk will consider methods of analysis of trials with
Spring term seminars 2011
partial nesting and multiple-membership due to therapist or
therapy group. Methods and issues will be illustrated by
data from trials of therapies for musculoskeletal and
psychological disorders. Sample size and power for trials
with multiple membership due to therapist will also be
considered.
Nick Parsons (WMS)
Tuesday 22
March
12:30 13:30
(Room A011)
Can Weather Forecasts be used to Predict Admission Rates
to UK Trauma Units?