PHLB09H3 Chap.3 Informed Consent, Biases and Heuristics
Informed Consent, Biases and Heuristics
Consent depends on how people actually decide
Informed consent assumes a patient who understands the options, forms an intention and chooses freely. Blumenthal-Barby's article asks how common cognitive biases and heuristics, the mental shortcuts studied since Tversky and Kahneman, interfere with each of those conditions.
Her answer is that bioethicists have looked too narrowly at framing effects, when the threat reaches every part of autonomous choice.
A framework with four conditions
Formal autonomy has three components in her account: understanding, intentionality, and freedom from controlling or alienating influences.
Effective autonomy adds a fourth question, whether the choices a person makes match the preferences that are authentically theirs.
Optimism and impact bias distort understanding; default bias and availability can bypass or reverse intentions; framing can leave a choice the person later disowns; sunk-cost bias opens a gap between values and action.
What to do about it
She doubts that simply removing biases, for example by presenting every frame, can work.
Countering them is more promising but paradoxical, because the tools of nudging often exploit the very mechanisms that threaten autonomy.
What this chapter covers
- 01
Formal and Effective Autonomy
- 02
Understanding and Intentionality
- 03
Alienating Influence
- 04
Optimism and Impact Bias
- 05
Framing Effects
- 06
Default and Sunk-Cost Bias
- 07
The Nudging Paradox
Worked example · free
Diagnose which part of consent a bias damages
- 2Name the bias and give the evidence the reading offers for it.
- 2Identify the threatened condition and explain why.
- 2Propose a response that improves understanding without steering the choice.
Key terms
- Heuristic
- A heuristic is a mental shortcut that simplifies judgement and often works well but can produce predictable errors.
- Effective Autonomy
- Effective autonomy is the match between a person's authentically held preferences and the choices they actually make.
- Alienating Influence
- An alienating influence is one that a person, reflecting on how a desire or decision formed, would not accept as their own.
- Framing Effect
- A framing effect is a change in choice caused by presenting logically equivalent information in different words, such as survival versus mortality.
- Default Bias
- Default bias is the strong tendency to stay with whatever option is already in place.
Informed Consent, Biases and Heuristics FAQ
What are the components of autonomous choice in Blumenthal-Barby's account?
She uses Faden and Beauchamp's three components of formal autonomy: understanding the relevant information, acting intentionally according to a plan, and acting free of controlling or alienating influences. She adds effective autonomy, which asks whether a person's actual choices match their authentic preferences. Each component comes in degrees, so what counts as enough depends on the context.
Why is framing not the only bias that matters for consent?
Framing has received the most attention in bioethics, but the reading surveys many other biases, such as optimism, impact, default, availability and sunk-cost bias. These affect different parts of autonomy, from understanding to the gap between values and action. A remedy that targets framing, such as presenting both frames, does nothing for these other threats.
Does nudging respect patient autonomy?
Blumenthal-Barby leaves the question open. She calls countering biases the more promising but more normatively challenging route, because nudges often use the same mechanisms that threaten autonomy. Supporters claim nudges steer people toward their real preferences without limiting liberty; she reports that claim cautiously and says more work is needed to decide when it holds.
Why does impact bias matter for medical decisions?
Impact bias leads people to overestimate how badly a future condition would affect them. In the reading, healthy people predicted life on dialysis would be miserable, while patients on dialysis rated their happiness close to healthy controls. A patient who refuses treatment because of such a forecast may be acting on a mistaken prediction rather than a settled value.
Exam move
Make flashcards that pair each bias with its definition, a clinical illustration from the reading and the autonomy condition it threatens. Practise the framing calculation by writing two equivalent risk statements and computing the difference in reported consent in percentage points.
Then take one bias and write two remedies, one that adds information and one that steers through a default, and argue which better respects autonomy. Finish by explaining the nudging paradox aloud in three sentences.
