Classic cases revisited: Oscar the cat and predicting death.

Uncertainty, although inherent in medicine, is rarely discussed in spite of being ubiquitous. Communication of uncertainty is poor due to anxiety associated with it, yet one could argue that lack of such disclosure could undermine trust, lead to perception of deceit, alter decision making and in some cases could invalidate the consent process. Predictions concerning end of life are particularly difficult and may lead to excessive or insufficient medical interventions. Acknowledging uncertainty when prognosticating outcomes, and in particular death, may help in facilitating patient-centred care in context of a critical illness.