Drains in Breast Reduction: How Good is the Recommendation Not to Use Them?

A clinical practice guideline (CPG) recommended not to use drains in breast reduction. This CPG was based on 3 randomized controlled trials (RCTs). The objective of this review was to double-check the methodological quality of the three RCTs. These RCTs were critically appraised using a) the Users' guide to RCT assessment for methodological quality, b) the CONSORT guideline for reporting quality, and c) the Cochrane risk of bias tool 2 (RoB 2) for risk of bias. Weaknesses were identified in all assessments for the three RCTs. Items with the poorest adherence in the User's guide to RCT included: "Were patients stratified?", "Was follow-up complete?", and "Were all clinically important outcomes considered?". The overall adherence to the CONSORT Reporting Checklist across all studies was moderate with 40.0%, 62.1% and 48.3% adherence. All 3 RCTs had a similar low to moderate risk of bias, with no areas with a high risk of bias. None of the studies took into consideration a single critical outcome (such as major hematoma) and the outcome's minimally important difference as the basis for the sample size and power calculation of the study. All three RCTs additionally lacked clear reporting of treatment effect sizes or precision of estimates. Our re-examination of the evidence questions the recommendation of the CPG. We believe that the recommendation should have been "we remain uncertain whether drains in breast reduction have a salutary effect". As such, we recommend that a methodologically robust RCTs be conducted to answer this question.