The review concluded that laparoscopic incisional hernia repair was superior to conventional open repair. There was a significantly lower infection rate but a higher rate of seroma with laparoscopic repair. Poor reporting of the review process, an unclear objective, incomplete inclusion criteria, unclear study quality and an inability to verify summary results limit the reliability of the authors’ conclusions.

The authors appear to compare the safety and efficacy of open versus laparoscopic incisional hernia repair.

MEDLINE was searched. Secondary sources were reported to be searched, but no other details were given.

Randomised studies that compared laparoscopic and open hernia repair were eligible for inclusion.

Wide variation was apparent within the included studies in terms of use of meshes, suturing techniques, sublay positioning and application of standard operating procedures. The included studies were published between 1997 and 2007. As relatively few randomised studies were identified, non-randomised studies were also included in the review. For most studies there was no differentiation between primary hernias, incisional hernias and recurrent hernias of the ventral abdominal wall. For most studies the alloplastic material of the mesh used for laparoscopic repair was expanded polytetrafluoroethylene (ePTFE); for open repair standard polypropylene (PP) meshes were used. The primary outcomes were complications, including their definitions and classifications. Other outcomes included surgery time, hospitalisation time and hernia recurrence.

It appeared that two independent reviewers performed the selection.

The validity criteria were randomisation, blinding and sample size. These were summarised in a table as present or absent (yes/no).

Two independent reviewers performed the validity assessment.

Data were extracted on outcome incidence. Advantages and disadvantages of the different alloplastic materials used for meshes were collected.

It appeared that two independent reviewers performed the data extraction.

A narrative synthesis was provided. For complications and certain other outcomes, results of the randomised studies alone were reported. Results for all the included studies were summarised for outcomes that related to surgical procedures and hernia recurrence. A discussion of the advantages and disadvantages of the different types of mesh used for hernia repair, mesh fixation and size of mesh and overlap was provided based on the results of the second search.

Seventeen studies were identified (n=1,833, range 26 to 426). There were four randomised studies (n=342, range 46 to 170). None of the studies was blinded. Eight studies were retrospective (n=1,139, range 26 to 426). Follow-up appeared to range up to 27 months.

Randomised study results (four studies): Incidence of infections was significantly lower in the laparoscopic group than the open repair group in three studies. Seromas were significantly more frequent with laparoscopy in two studies. Results for surgery time were mixed, which the authors thought was related to the different fixation method for the mesh with laparoscopy. Defect and prosthesis size were smaller in the laparoscopy group in two studies.

Laparoscopic incisional hernia repair showed superiority compared to conventional hernia repair in some randomised studies as well as in a large number of retrospective analyses and in case-control studies. No long-term results with a high level of evidence were available.

Study design and relevant interventions were clear. There was some discrepancy between the inclusion criteria and included studies in terms of design. The characteristics of the included population were unclear. An adequate summary of randomised studies was provided; the extent to which this was complete for other studies was unclear. These aspects potentially impact on the reliability and generalisability of the review. Not all sources used for the search were clearly described; it was unclear whether unpublished studies or studies published in languages other than English were included and search dates were not given. Publication bias did not appear to be assessed. Some criteria related to study quality were assessed, but few details of study design were reported and this made it difficult for the reader to assess overall study quality. Efforts to reduce error and bias in validity assessment were explicitly stated; study selection and data extraction appeared to follow the same procedure. Few study details were reported. Although sample sizes were reported, no numerical data were reported for study results which would enable the reader to gauge the size of an effect and compare the results of different studies. No explanation was given for providing a narrative synthesis.

The poor reporting of the review in terms of an unclear objective, incomplete inclusion criteria, limited reporting of the review process, unclear study quality and inability to verify summary results potentially limits the reliability of the authors’ conclusions.

Practice: The authors did not report any implications for practice.

Research: The authors identified a need for additional well-designed randomised double-blind trials with long-term follow-up of five years minimum and with sufficient power. They recommended: use of identical alloplastic materials for both procedures; well-defined operational protocols that included mesh placement in open repair and standardised mesh fixation; well-defined complications that discriminated between procedure-related and procedure-independent complications. The authors described one on-going randomised study.

Not stated.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.