• Publications
  • Influence
Covariate association eliminating weights: a unified weighting framework for causal effect estimation
  • S. Yiu, L. Su
  • Mathematics, Medicine
  • Biometrika
  • 1 September 2018
Summary Weighting methods offer an approach to estimating causal treatment effects in observational studies. However, if weights are estimated by maximum likelihood, misspecification of the treatmentExpand
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Two-part models with stochastic processes for modelling longitudinal semicontinuous data: Computationally efficient inference and modelling the overall marginal mean
  • S. Yiu, B. Tom
  • Mathematics, Medicine
  • Statistical methods in medical research
  • 27 March 2017
Several researchers have described two-part models with patient-specific stochastic processes for analysing longitudinal semicontinuous data. In theory, such models can offer greater flexibility thanExpand
  • 3
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Two-Part and Related Regression Models for Longitudinal Data
Statistical models that involve a two-part mixture distribution are applicable in a variety of situations. Frequently, the two parts are a model for the binary response variable and a model for theExpand
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Clustered multistate models with observation level random effects, mover–stayer effects and dynamic covariates: modelling transition intensities and sojourn times in a study of psoriatic arthritis
Summary In psoriatic arthritis, it is important to understand the joint activity (represented by swelling and pain) and damage processes because both are related to severe physical disability. TheExpand
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Exploring the existence of a stayer population with mover–stayer counting process models: application to joint damage in psoriatic arthritis
  • S. Yiu, V. Farewell, B. Tom
  • Computer Science, Medicine
  • Journal of the Royal Statistical Society. Series…
  • 19 October 2016
TLDR
This paper demonstrates that, when fitted to the same data (real psoriatic arthritis data and simulated data), these models provide widely varying conclusions on the existence and proportion of a stayer population. Expand
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SAT0186 DEVELOPING PREDICTORS OF GLOBAL BILAG TREATMENT RESPONSE IN PATIENTS WITH LUPUS NEPHRITIS: MORE LESSONS FROM THE ASPREVA LUPUS MANAGEMENT STUDY GROUP (ALMS) DATA
Background: There is considerable debate regarding the most appropriate outcome measures for clinical trials in systemic lupus erythematosus (SLE). We propose that studying changes in diseaseExpand
A joint modelling approach for multistate processes subject to resolution and under intermittent observations
  • S. Yiu, B. Tom
  • Medicine, Mathematics
  • Statistics in medicine
  • 17 October 2016
Multistate processes provide a convenient framework when interest lies in characterising the transition intensities between a set of defined states. If, however, there is an unobserved event ofExpand
Joint calibrated estimation of inverse probability of treatment and censoring weights for marginal structural models.
  • S. Yiu, L. Su
  • Computer Science, Mathematics
  • Biometrics
  • 13 June 2018
TLDR
In this paper, we propose a joint calibration approach to CBW estimation for MSMs that can accommodate (1) both time-varying confounding and dependent censoring, (2) binary and non-binary treatments, (3) eventual outcomes and longitudinal outcomes. Expand
Trivariate mover‐stayer counting process models for investigating joint damage in psoriatic arthritis
In psoriatic arthritis, many patients do not develop permanent joint damage even after a prolonged follow‐up. This has led several authors to consider the possibility of a subpopulation of stayersExpand