Global PaedSurg Research Training Fellowship Session 2: 30th November 2018 Title: Choosing your study design Tutor: Assoc Prof Emily Smith, Baylor University, Texas
Objectives • To gain an understanding of different study designs and the hierarchy of evidence • To weigh up the pros and cons of using different study designs • To consider which study design you will use for your own study • - opportunity to ask questions & discuss your projects
Systematic review & Meta-analysis: PRISMA-P . http://www.prisma-statement.org/Extensions/Protocols.aspx
Systematic Review Resource https://libguides.kcl.ac.uk/systematicreview/home
Cochrane Library https://www.cochranelibrary.com/about/author-information
Meta-analysis Results represented in a Forest Plot
Randomised Controlled Trial http://globalsurg.org/projects/clinical-trials/falcon/
Randomised Controlled Trial (RCT) Must follow CONSORT guidelines for reporting RCTs. 25 item checklist. http://www.consort-statement.org
Non-Randomised Clinical Trial Link to registered protocol: https://clinicaltrials.gov/ct2/show/NCT03724214?cond=gastroschisis&rank=1
Why not randomised? • This study involves implementing a new care package with many components: pre-hospital and in-hospital. • It involves a change in the system and a change in culture and altitudes towards managing neonates with gastroschisis. • Hence, once the new care package is implemented it will be impossible to randomise some neonates to the old care. • A cluster randomised controlled trial would be an alternative. • This is more complex to establish.
Cohort study • A cohort study is a particular form of longitudinal study that sample a cohort (a group of people who share a defining characteristic, typically those who experienced a common event in a selected period, such as birth or a particular operation or a specific condition(s)), performing a cross-section at intervals through time. • Prospective or retrospective
Sample size calculation • Required to know how many patients to include in your study. • Too few will result in your study not showing a significant difference simply because you didn’t have enough patients rather than there being no difference. • Too many patients is a waste of time and may be unethical if it wastes patients time or exposes them to a treatment without proven effectiveness (or even harm).
STROBE Guidelines • For use in observational studies: cohort & case-control https://www.strobe-statement.org/index.php?id=strobe-home
Population Surveys To define surgical burden in a population: household surveys
Institutional Surveys • To define current surgical capacity: institutional surveys • PIPES • PediPIPES • WHO Situational Analysis Tool • Paediatric WHO Situational Analysis Tool • GAPS
Case reports • Individual cases or a series of cases • Typically rare and have not been published widely before • Provides a new insight • Information provided is useful to other clinicians • Includes a review of the literature on that topic and how the new case adds to that evidence • BMJ guide to writing a case report: • https://www.bmj.com/company/wp-content/uploads/2015/08/BMJ-Case-Reports-4pp-A4-Leaflet-2-2.pdf
Animal/ In vitro studies • These typically require a well established laboratory and team • Commonly costs a lot of money • To establish these skills – undertake research within a laboratory under the guidance of an experienced supervisor • There are opportunities to get involved in collaborative genetic studies such as the DHREAMS and CARE studies detailed on our Global PaedSurg blog: • http://globalpaedsurg.com/care-and-dhreams-studies-an-opportunity-to-enhance-our-genetic-understanding-of-congenital-anomalies/
Expert opinion • Surveys of healthcare professionals
Expert opinion • Delphi process
Qualitative Research • Qualitative Research is primarily exploratory research. • It is used to gain an understanding of underlying reasons, opinions, and motivations. • It provides insights into the problem or helps to develop ideas or hypotheses for potential quantitative research. • Commonly uses interviews or group discussions.
Discussion • Any questions? • Has anyone got a study they are planning, which they could share? This will enable the group to discuss the study design and learn from it.
Resources • These have been detailed throughout the presentation both on the slides and in the textbox beneath each slide • Research skills cannot be learned though courses alone • They are learned through undertaking research with some background knowledge and resources from courses in combination with support (mentorship and supervision) • Researchers gain experience over many years by undertaking and participating in many studies
Thank you for listening, any questions? Naomi Wright: email@example.com @PaedsSurgeon @GlobalPaedSurg #GlobalPaedSurg www.globalpaedsurg.com