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Study design.

The study design involves a survey of current practice and clinical uncertainty, a consensus exercise, and a qualitative study of patient and clinician views (focus groups, interviews; leading to the design of a trial.


We will recruit clinicians from UK maternity hospitals and neonatal units where preterm babies are delivered /cared for making use of our networks (labour ward leads. Preterm Birth Network, RCOG clinical study group network, British Maternal and Foetal Medicine Society members, Royal College of Midwives) to ensure wide coverage. Women will be recruited through our charity partners Tommy’s and BLISS, through social media advertisements (which we and others have previously found to be very effective in identifying volunteers) and via community routes and from NHS sites with diverging clinician views about optimal mode of delivery.

Strategy for reviewing literature

A scoping exercise identified 54 publications and 6 registered systematic review protocols. (Note, the purpose of this literature review is to determine the populations of preterm babies and the clinical scenarios where there is clinical uncertainty about the mode of delivery; not the feasibility of recruitment to a randomised trial). These clinical uncertainties will be explored in the survey and the consensus exercise; the qualitative study will then focus on willingness to recruit to / participate in a trial to address areas of clinical uncertainty.

Target population and inclusion criteria

For the research question: (inclusion) women in preterm labour with a singleton or twin pregnancy, with a cephalic or breech presentation, at between 22+0 and 36+6 weeks gestation; (exclusion) women and babies for whom there is a “medical” reason to avoid labour (e.g. very severe growth restriction, fulminating pre-eclampsia). We will not deliberately exclude participants who have experienced adverse events because of the issues above (e.g. neonatal death, stillbirth) but we will be mindful of the need to manage this sensitively.  For the survey and focus groups/interviews: (inclusion) clinicians who provide clinical care for such women. Women who have had previous experience or are at high risk of these events.

Health technologies being assessed

Methods of delivery: caesarean section compared with vaginal delivery.

Measurement of costs and outcomes

  1. clinical uncertainties, opinion and practice and
  2. willingness to recruit to/participate in a trial to address these uncertainties
  3. outline of RCT with approximate cost.

Sample size

  • 200 Opinions survey,
  • 200 Clinicians for current practice,
  • Delphi exercise 2 groups of 10-20,
  • Qualitative Interviews n=25.
  • Women: 6-8 focus groups total n=30-60.

Project timetables

  • Months 1-4: Complete surveys to establish current practice and outstanding research questions (including analysis).
  • Months 5-9: Delphi consensus exercise, design of trial(s), mock-up of trial protocol(s) and information sheets and design of vignette(s).
  • Months 10-22: Qualitative study, data analysis.
  • Months 23-24: report writing.


The Study is funded by the NIHR Health Technology Assessment Programme (project number 17/22/02). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the HTA.