, Volume 22, Issue 2, pp 215–226 | Cite as

A systematic methodological review of reported perioperative variables, postoperative outcomes and hernia recurrence from randomised controlled trials of elective ventral hernia repair: clear definitions and standardised datasets are needed

  • Samuel G. Parker
  • C. P. J. Wood
  • J. W. Butterworth
  • R. W. Boulton
  • A. A. O. Plumb
  • S. Mallett
  • S. Halligan
  • A. C. J. Windsor



This systematic review assesses the perioperative variables and post-operative outcomes reported by randomised controlled trials (RCTs) of VH repair. This review focuses particularly on definitions of hernia recurrence and techniques used for detection.


Our aim is to identify and quantify the inconsistencies in perioperative variable and postoperative outcome reporting, so as to justify future development of clear definitions of hernia recurrence and a standardised dataset of such variables.


The PubMed database was searched for elective VH repair RCTs reported January 1995 to March 2016 inclusive. Three independent reviewers performed article screening, and two reviewers independently extracted data. Hernia recurrence, recurrence rate, timing and definitions of recurrence, and techniques used to detect recurrence were extracted. We also assessed reported post-operative complications, standardised operative outcomes, patient reported outcomes, pre-operative CT scan hernia dimensions, intra-operative variables, patient co-morbidity, and hernia morphology.


31 RCTs (3367 patients) were identified. Only 6 (19.3%) defined hernia recurrence and methods to detect recurrence were inconsistent. Sixty-four different clinical outcomes were reported across the RCTs, with wound infection (30 trials, 96.7%), hernia recurrence (30, 96.7%), seroma (29, 93.5%), length of hospital stay (22, 71%) and haematoma (21, 67.7%) reported most frequently. Fourteen (45%), 11 (35%) and 0 trials reported CT measurements of hernia defect area, width and loss of domain, respectively. No trial graded hernias using generally accepted scales.


VH RCTs report peri- and post-operative variables inconsistently, and with poor definitions. A standardised minimum dataset, including definitions of recurrence, is required.


Ventral hernia Abdominal wall reconstruction Standardisation 



This work was supported by the United Kingdom National Institute for Health Research (NIHR) via Research for Patient Benefit grant PB-PG-0816-20005 and the University College London Hospitals Biomedical Research Centre (SH). The views expressed in this publication are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health.


Funding has recently been received from the National Institute for Health Research and from Allergan PLC. Neither funders have been involved in the planning, methodology, analysis or write up of the research. National Institute of Health Research, Room 132, Richmond House, 79 Whitehall, London, SW1A 2NS. Allergan Plc, Clonshaugh Business and Technology Park, Coolock, Dublin, D17 E400, Ireland.

Compliance with ethical standards

Conflict of interest

Windsor A.C.J. declares conflicts of interest not directly related to the submitted work; educational grants and speaker for: BARD, LifeCell and Cook. Parker S.G, Wood C.P.J, Butterworth J.W, Boulton R.W, Plumb A.A.O, Mallet S and Halligan S declare no conflict of interest.

Ethical approval

Ethical permission is not required by our centre for systematic reviews of available primary literature.

Human and animal participants

This article does not contain any studies with human participants performed by any of the authors.

Informed consent

This article does not include patients, and therefore informed consent was not applicable.

Supplementary material

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Supplementary material 1 (DOCX 100 kb)
10029_2017_1718_MOESM2_ESM.docx (126 kb)
Supplementary material 2 (DOCX 125 kb)
10029_2017_1718_MOESM3_ESM.docx (99 kb)
Supplementary material 3 (DOCX 99 kb)


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Copyright information

© Springer-Verlag France SAS, part of Springer Nature 2018

Authors and Affiliations

  • Samuel G. Parker
    • 1
  • C. P. J. Wood
    • 1
  • J. W. Butterworth
    • 2
  • R. W. Boulton
    • 1
  • A. A. O. Plumb
    • 3
  • S. Mallett
    • 4
  • S. Halligan
    • 3
  • A. C. J. Windsor
    • 1
  1. 1.The Abdominal Wall Unit, University College London HospitalUniversity College London Hospitals NHS Foundation TrustLondonUK
  2. 2.Upper Gastrointestinal Surgery Department, St Mary’s HospitalImperial College Healthcare NHS TrustLondonUK
  3. 3.Centre for Medical ImagingUniversity College LondonLondonUK
  4. 4.Institute of Applied Health Sciences, College of Medical and Dental SciencesUniversity of BirminghamBirminghamUK

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