Observational data, causal inference & subarachnoid haemorrhage
Research type
Research Study
Full title
Observational data, causal inference & subarachnoid haemorrhage
IRAS ID
328791
Contact name
H Patel
Contact email
Sponsor organisation
Northern Care Alliance NHS Foundation Trust
Duration of Study in the UK
1 years, 0 months, 1 days
Research summary
Evidence-based therapeutic decision-making uses the best empirical evidence about cause and effect relationships (causal effects) between treatments and outcome in the light of the patient's characteristics. It is widely accepted in the medical community that such evidence should ideally be generated via randomised experimental studies (RCTs)
Unfortunately, randomised experiments are not universally feasible or practical, especially in low volume subspecialties (e.g., Neurosurgery) where the randomisation of a sufficient number of participants may be problematic on practical and/or ethical grounds
aSAH is a type of brain haemorrhage that affects about 8000 patients in the UK a year. There have been significant improvements in processes of care but despite this 10-15% of the hospitalised patients die, and only 50% of patients are discharged home without physical disability.
It is well recognised that aSAH is a heterogeneous condition and that patients may experience a number of complications following admission There is currently a lack of evidence to inform a rationale therapeutic approach to these, and this is an important area of research. Of special interest to our collaboration are the research recommendations in the recently published NICE aSAH guidelines about the treatment of delayed cerebral ischaemia (DCI) and use of an external ventricular drain (EVD)
DCI is considered the most important, potentially treatable, cause of mortality and morbidity following aSAH. It is characterised by a reduction in cerebral blood flow (CBF) which can be progressive, causing cerebral infarction and long-lasting disability or death. There has been an attempt to compare the two therapeutic approaches via RCT. Due to difficulties of patient recruitment , the trial had insufficient power to show a treatment effect
We have performed a naïve (non-causal) analysis of the UK and Ireland SAH dataset (UK&ISAH) and showed that insertion of an EVD is associated with a poor outcome.
We propose a proof of principle study using causal inference methodology within a well-designed registry study to help shed light on clinical intervention effects that RCT’s have not been (nor will probably ever be) able to clarify
REC name
Yorkshire & The Humber - Leeds East Research Ethics Committee
REC reference
23/YH/0125
Date of REC Opinion
1 Jun 2023
REC opinion
Favourable Opinion