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  • Jan 22 / 2021
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Current Research, Ryan Field

RESEARCHER SHOWCASE: Ryan Field and Joint Modelling in Heart Failure

Ryan is a second year PhD candidate in Public Health, investigating joint modelling within heart failure.

Joint Modelling is a statistical technique for modelling longitudinal repeat measures together with survival data.

The Longitudinal data is typically modelled using an LME (Linear mixed effects model), whereas the survival data is modelled using standard regression survival models such as Cox Proportionate Hazards Model

These models are then linked through an association structure via their shared random effects, i.e. the individual patients or participants, resulting in a joint model

For my PhD I am exploring the uses of Joint Modelling within heart failure, with the aims to produce a prognostic model using repeat measures

Some advantages of Joint Modelling are:

  • It can reduce Bias both with respect to treatment effect and (bias) due to censoring
  • It is more efficient than traditional Models
  • And it allows the use of repeat measure while inherently accounting for measurement error and allowing for different follow-up times

On the other hand, some disadvantages are:

  • It requires repeat measurements to be integrated in the study design 
  • More complex and harder to fit than traditional models thus taking longer to fit
  • And not as well known as traditional model

Currently in heart failure  the primary focus is on the association of longitudinal repeat measurements and an endpoint such as a composite endpoint

Longitudinal measurements include: Quality of Life and Bio Markers such as: Natriuretic Peptides e.g. NT-ProBNP and Renal markers such are Creatinine

Other novel applications include physical activity as reported by an implanted device such as an ICD

There are a limited number of studies looking at prognostic models and individual patient survival predictions

My research aims to focus more on the prognostic value of bio markers in Heart Failure using data collected from randomised control trials in an effort to improve the existing prognostic models and create new prognostic models using joint modelling.

From the image we can see the results from a joint model presented as a graph looking at a patient specific trajectory with the longitudinal measurements on the left and the survival probability on the right.

The model assumes that the patient has survived until the last measurement and calculated the survival probability from that point.

The joint model can also provide coefficients from both the longitudinal and survival models with the latter being exponentiated to produce a hazard ratio e.g. of treatment effect or the association of the biomarker through an association parameter.

Ryan can be contacted at:

Twitter: @Ryan_J_Field

Email: r.field.1@research.gla.ac.uk

This presentation was presented as part of an IHW PGR half-day conference, All aboard


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  • Sudell M, Kolamunnage-Dona R, Tudur-Smith C. Joint models for longitudinal and time-to-event data: a review of reporting quality with a view to meta-analysis. BMC Med Res Methodol. 2016;16(1):168.
  • Rizopoulos D. JM: An R package for the joint modelling of longitudinal and time-to-event data. J Stat Softw. 2010 Jul;35(9):1–33.
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  • Rizopoulos D. Joint Models for Longitudinal and Time-to-Event Data: With Applications in R. 2012.
  • Dec 18 / 2020
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Alexandra Rose, Current Research, Uncategorized

RESEARCHER SHOWCASE: Alexandra Rose and The assessment of mood after severe brain injury

Alexandra Rose (CPsychol) is a Principal Clinical Psychologist based in a London hospital, working with patients with brain injury. Her research is focused on understanding the assessment of mood, depression and distress after severe brain injury. She is supervised by Professor Jonathan Evans and Dr Breda Cullen. Alex is in the 2nd year of pursuing her PhD in Psychological Medicine. She is studying remotely whilst continuing her clinical work and is being assisted financially by a Francis Newman Foundation grant.  The following is part of her project exploring the assessment of mood after severe brain injury.

  • Dec 17 / 2020
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Current Research, Warut Aunjitsakul

RESEARCHER SHOWCASE: Warut Aunjitsakul and maintenance mechanisms of social anxiety disorder in people with psychosis

Warut Aunjitsakul is a psychiatrist and clinical instructor from Prince of Songkla University, Thailand and very keen to develop theoretical understanding and improve psychological intervention in people with psychosis. He is now pursuing his PhD in Psychological Medicine.  

The following is part of Warut’s PhD project aiming to understand the maintenance mechanisms of social anxiety disorder in people with psychosis. 

  • Dec 14 / 2020
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Current Research, Meigan Thomson

RESEARCHER SHOWCASE: Meigan Thomson and Barriers and Facilitators of Weight Loss in participants of a Behavioural Weight Loss Programmes.

Meigan is a PhD student based in the MRC/CSO Social and Public Health Sciences unit and is supervised by Professor Sharon Simpson, Dr Anne Martin, Dr Emily Long and Dr Jennifer Logue. Meigan’s PhD topic is Understanding the Barriers & Facilitators of Weight Loss in adults participating in Behavioural Weight Loss Programmes.  

  • Jul 28 / 2020
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Current Affairs, Patrice Reid

BLM. By Patrice Reid

baby resting head on man's cheek. father and son.

The embrace – Two generations of black men
Photo by: Trudy Dawson, Edited by: Patrice Reid
Copyright © 2020 Trudy Dawson.

The Black Lives Matter (BLM) movement evokes many feelings and thoughts. The fact that I have to write ‘black lives matter’ or the fact that this string of words has to be said is unreal. My mind is still coming to grips with the slogan. I am coming to grips with the fact that today the BLM chant echoes centuries-old outcries for equality against chattels and injustices. Chattels and injustices imposed by one set of humans onto another who are phenotypically different, and that remain due to notions of otherness.

It is unfair. It is wrong. It is heart-breaking. It hurts.

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  • Jun 22 / 2020
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Patrice Reid, PhD Experience

Covid series: Today’s Start. By Patrice Reid

This piece is part of a series collecting the experiences of researchers during the current COVID-19 pandemic.

Patrice Reid is a Commonwealth Scholar pursuing her Ph.D. in Psychological Medicine. Her research is focused on the development and field testing of a culturally grounded digital intervention to address alcohol and marijuana abuse in young Jamaicans. The following is a reflective piece by Patrice on living in lock-down.  

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