Evidence Review Process - ESRA

Evidence Review Process

The initial Prospect procedure-specific review for thoracotomy was completed in 2008, and is now archived on the Prospect website. This update consists of a literature search covering any peer-reviewed paper published between the years 2008 and 2015, inclusive.

Following the Cochrane Collaboration convention for a systemic review and in line with the Prospect Methodology for performing a procedure-specific review, a literature search of the Medline, Embase and Cochrane databases was conducted using the following search terms.

750 manuscripts were initially retrieved for the review; after preliminary screening 696 were excluded – mainly because they were not written in the English language. Or were concerned with chronic pain syndromes, or consisted only of case reports or had no objective pain scoring in the trial.

55 manuscripts were included; 49 were prospective randomised controlled studies and had a specific patient study group for thoracic surgery; 6 were meta-analyses.

Following the data analysis, the information was collated into pre-, intra-, and post- operative phases and compared with the existing recommendations from the original review. Where appropriate, the existing recommendations remained unchanged if there was no new data, strengthened where new data supported the existing, or removed if the new data contradicted the earlier recommendations.

The summary recommendations are listed separately. Recommendations from the initial review that were contraindicated by the new review have been removed but will still be available, for comparison, in the archived review.

An explanation of PROSPECT methodology and Working Group processes can be found at the following link: PROSPECT methodology primer

For the Thoracotomy review, the Subgroup members were:

• Professor Francis Bonnet (PROSPECT Working Group member)
• Ludric Popof
• Jessica Pessayre

  • Systematic review of the literature from [2008-2015] using MEDLINE and EmBASE, following the protocol of the Cochrane Collaboration
  • Inclusion of randomised/controlled studies assessing analgesic, anaesthetic or operative techniques in Thoracotomy and reporting pain assessment, required analgesia or adverse events (Thoracotomy: Search strategy)
  • 55 studies included; 49 randomised controlled trials and 6 meta-analyses (Thoracotomy: Included Studies)
  • 696 studies excluded after full-text screening (Thoracotomy: Excluded studies)
  • The most common reason for exclusion was mainly because they were not written in the English language, or were concerned with chronic pain syndromes, or consisted only of case reports or had no objective pain scoring in the trial Study quality assessments

Thoracotomy: Sources and levels of evidence (LoE) determine the Grades of Recommendation (GoR)

GoR are assigned according to the overall LoE, which is determined by the quality of studies cited, the consistency of evidence and the source of evidence:

Thoracotomy: levels of evidence and GoRs of recommendation

Sources of evidence in PROSPECT

The evidence for prospect is derived from three separate sources, and this evidence is taken into consideration by the prospect Working Group to determine the prospect recommendations:

  • Procedure-specific evidence derived from the systematic reviews of the literature
  • Current practice – A commentary on the interventions from the members of the prospect Working Group
  • Practical PROSPECT recommendations are based on all the information

Study quality assessment

For the Thoracotomy review, the quality of procedure-specific evidence has been assessed according to NICE methodology, to determine the possibility of selection bias, performance bias, attrition bias and detection bias (http://www.nice.org.uk/article/pmg6b).

Quality indicators used to determine the LoE of individual studies:

  • Allocation concealment: indicates whether there was adequate prevention of foreknowledge of treatment assignment by those involved in recruitment (in the table below, A=adequate, B=unclear, C=inadequate, D=not used). Empirical research has shown that trials with inadequate or unclear allocation concealment report significantly greater estimates of treatment effect than those trials in which concealment was adequate (Chalmers 1983, Schulz 1995, Moher 1998). Allocation concealment was found to be more important for preventing bias than other aspects of study quality, such as generation of the allocation sequence and double-blinding (Chalmers 1983, Schulz 1995, Moher 1998, Higgins and Green 2005, http://handbook.cochrane.org/)
  • Statistical analyses and patient follow-up: indicates whether statistical analyses were reported, and whether patient follow-up was greater or less than 80%.
  • Numerical scores (total 1–5) for study quality: assigned using the method proposed by Jadad 1996, to indicate whether a study reports appropriate randomisation, double-blinding and statements of possible withdrawals. Empirical research found that low-quality trials were associated with an increased estimate of treatment benefit compared with high-quality trials (Moher 1998)

Quantitative analyses

No meta-analyses were performed due to a limited number of studies of homogeneous design that reported similar outcome measures. Therefore, the procedure-specific evidence was only assessed qualitatively.