This review concluded that there was no evidence to suggest that endoscopic band ligation (EBL) plus sclerotherapy is more effective than EBL alone in the secondary prevention of oesophageal variceal hemorrhage. Given that the findings were based on a small number of trials of poor quality, the authors' conclusions should be interpreted with some caution.

To compare the efficacy and safety of combined endoscopic band ligation (EBL) and sclerotherapy with EBL alone for the secondary prophylaxis of oesophageal variceal haemorrhage.

MEDLINE and EMBASE were searched from January 1990 to January 2002; the search terms were reported. In addition, the bibliographies of included studies and key review articles were checked. Abstracts from relevant scientific meetings were also consulted. Authors were contacted for further information where necessary. There was no language restriction and an interpreter was employed to translate all non-English citations.

Study designs of evaluations included in the review

Randomised controlled trials (RCTs) were eligible for inclusion in the review.

Specific interventions included in the review

Studies of combination endoscopic therapy (band ligation and sclerotherapy given during the same endoscopic session) versus EBL alone were eligible for inclusion in the review.

Participants included in the review

Adults were eligible for inclusion in the review. The participants in the included studies comprised those with chronic liver disease, active or recent oesophageal variceal hemorrhage, and upper gastrointestinal bleeding due to oesophageal varices. The majority of the patients had known cirrhotic portal hypertension.

Outcomes assessed in the review

The inclusion criteria for outcomes comprised at least one from re-bleeding, mortality, complications, and endoscopic treatment sessions required for variceal obliteration. The mean length of follow-up in the included studies ranged from 7 to 22 months.

How were decisions on the relevance of primary studies made?

Two reviewers independently made decisions on the relevance of studies for inclusion in the review, using a standardised screening form. Any disagreements were resolved by consensus.

The authors employed the Jadad scale to assess the validity of the primary studies. The assessment criteria were applied using a quality scoring form. However, the authors did not supply any further details regarding the specific process of assessing validity.

Although a standardised data extraction form was used, the authors did not state how the data were extracted, or how many reviewers performed the data extraction.

Data was collected in order to calculate risk ratios (or relative risk, RR) for dichotomous outcomes (e.g. oesophageal variceal re-bleeding and mortality) and effect sizes for continuous outcomes (e.g. the number of endoscopic sessions required for variceal obliteration). Data were also collected on the incidence of adverse events.

How were the studies combined?

The studies were combined by meta-analysis, using a random-effects model to pool the risk ratios. Publication bias was assessed using funnel plots, a correlation test and a regression asymmetry test.

How were differences between studies investigated?

Statistical heterogeneity was assessed between trials via the use of chi-squared analysis.

Eight RCTs were included in the analysis, which contained a pooled sample of 520 participants.

In the validity assessment, 5 trials achieved 2 points on the Jadad scale and 3 trials scored 1 point; the maximum possible score was 5 points.

Results from 5 RCTs measuring oesophageal re-bleeding revealed that the pooled RR between groups was not significant at 1.05 (95% confidence interval, CI: 0.67, 1.64, P=0.83), and there was no evidence of publication bias or significant heterogeneity (P=0.68) between the studies. No significant differences were noted for mortality amongst the 7 studies that reported this outcome, given that the RR was 0.99 (95% CI: 0.68, 1.44, P=0.96). Again, there was neither statistical heterogeneity across the studies (P=0.59), nor any publication bias. In terms of variceal obliteration, the pooled results from all 8 studies revealed no significant difference in the mean number of endoscopic sessions required. The RR was 0.23 (95% CI: 0.055, 0.51, P=0.11). However, significant heterogeneity was found amongst these studies (P=0.01).

The analysis of adverse events found no significant differences in perforation, infection, posthemostasis ulcer bleeding, or cardiopulmonary arrest. However, the incidence of oesophageal stricture formation was found to be higher with combination therapy (8.9) than with EBL alone (0.38%), and this difference was statistically significant.

There was no evidence to suggest that combination therapy (EBL plus sclerotherapy) is more effective than EBL alone. In addition, combination therapy was found to have a higher incidence of oesophageal stricture formation.

The question and inclusion criteria were clearly stated for this review. The search strategy was limited in its consideration of only two databases, but this was appropriately supplemented by handsearches and reference to relevant conference proceedings. The multi-language consideration was a particular strength of the search strategy. Although it was clear that attempts had been made to reduce or assess bias in some parts of the review process (e.g. during the study selection phase and in examining for publication bias), the same attempts were not evident in relation to other parts of the review process (such as the assessment of validity and the data extraction phase).

Adequate details of the included studies were reported; however, the authors acknowledged that two of the 8 trials presented only limited information in abstract form. The methods of synthesis appeared appropriate and the results of tests for heterogeneity were largely encouraging. However, given that some results were based upon a small number of trials of poorer quality, and that some parts of the review process cannot be considered exempt from bias, the reliability of the authors' conclusions is not clear.

The authors did not state any implications for practice or further research.

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.