Flawed, futile, and fabricated—features that limit confidence in clinical research in pain and anaesthesia: a narrative review

The randomised controlled trial is the foundation of clinical research; yet there is concern that many trials have flaws in design, conduct, and reporting that undermine trustworthiness. Common flaws in trials include high risk of bias, small size, outcomes irrelevant to clinical care and patient's experience, and inability to detect efficacy even if present. These flaws carry forward into systematic reviews, which can confer the label of ‘high-quality evidence’ on inadequate data. Trials can be futile because their flaws mean that they cannot deliver any meaningful result in that different results in a small number of patients would be sufficient to change conclusions. Some trials have been discovered to be fabricated, the number of which is growing. The fields of anaesthesia and pain have more fabricated trials than other clinical fields, possibly because of increased vigilance. This narrative review examines these themes in depth whilst acknowledging an inescapable conclusion: that much of our clinical evidence is in trouble, and special measures are needed to bolster quality and confidence.