Table 2

Forcing functions

Forcing function	Comment	Examples
Statistical and clinical prediction rules (SPRs and CPRs)	Explicit SPRs and CPRs typically equal or exceed the reliability of expert ‘intuitive’ judgement. Easy to use, they address significant issues	▸ The superiority of SPRs and CPRs over clinical judgement has been shown.56 Physicians demonstrate pretest probability variability in specific diagnoses57
Cognitive forcing strategies (CFSs)	CFSs are special cases of forcing functions that require clinicians to internalise and apply the forcing function deliberately. They represent a systematic change in clinical practice. CFSs may range from universal to generic to specific	▸ Training might be given to identify situations (cognitive overloading, fatigue, sleep deprivation, others) that promote the use of heuristics and biases leading to decision errors. Clinical scenarios can be identified in which particular biases are likely to occur 1and explicit CFSs can be taught to mitigate them58
Standing rules	May be used in certain clinical settings that require a given diagnosis not be made unless other must-not-miss diagnoses have been ruled out	▸ No published examples
General diagnostic rules in clinical practice	Many diagnostic ‘rules’ are often passed to trainees that are intended to prevent diagnostic error	▸ Specific tips to avoid diagnostic error59
Rule Out Worst-Case Scenario (ROWS)	A simple but useful general strategy to avoid missing important diagnoses	▸ No published examples
Checklists	A standard in aviation and now incorporated into medicine in intensive care units, surgery and in the diagnostic process60	▸ Catheter-related bloodstream infections were sustainably reduced by clinicians’ adopting five evidence-based procedures on a checklist and reminders such as reinforcing strategies61 ▸ The implementation of a surgical safety checklist led to reductions in death rates and complications in non-cardiac surgery in a multicenter study62
Stopping rules	Stopping rules are an important form of forcing functions—they determine when enough information has been gathered to make an optimal decision63 64	▸ No published examples
Consider the opposite	Seeking evidence to support a decision opposite to your initial impression may be a useful way of forcing consideration of other options	▸ Experimental studies in psychological research have shown considering the opposite counteracted biases,25 65 66 for example, a consider-the-opposite strategy led to less biased judgements of personality traits67
Consider the control	Causal claims are often made without an appropriate control group67	▸ No published examples