Why are placebos used in research?

Placebos are used in medical research to help establish whether a trial treatment is effective. The placebo effect describes how even receiving a “dummy” treatment (e.g., a sugar pill or saline infusion) can lead to improvement in symptoms.

For this reason, researchers use a control group who receives the placebo and a treatment group who receive the experimental drug. The effectiveness of the new treatment is measured by how much better it is at treating the condition compared with the control group.

In most cases, researchers use a double-blind experimental design to reduce bias.

Bias: Other interesting questions

What is the difference between confirmation bias and availability bias?: The difference between confirmation bias and availability bias is that they refer to two separate ways of processing information.

Availability bias (or availability heuristic) describes how people tend to make decisions based on information that is readily available to them. This is often because it is more recent or because it has received coverage in the media.

Confirmation bias describes the tendency to latch on to information that confirms ideas that we already hold.
What is a historical example of survivorship bias?: During World War II, early studies of damage inflicted on US bombers focused on the damage sustained by planes that made it back to their bases. The decision was made to reinforce the areas most often damaged by enemy fire.

It was soon realized, however, that this was excluding the most important sources of data—the planes that never made it back to base. It became apparent that the most important places to reinforce the craft were where they had not been hit. Because the planes that were hit there hadn’t returned.

This is an excellent historical example of survivorship bias because the planes were literally the survivors, but they lacked the most important data.
What are some examples of selection bias?: There are many types of selection bias, including:

Attrition bias

Sampling bias

Survivorship bias

Self-selection bias

Undercoverage bias

Non-response bias
What is the priming effect?: The priming effect describes the way our brains use already-received information to help understand subsequent information. It should not be confused with the primacy effect, or primacy bias.

A common example is that when primed with the word “yellow,” we process the word “banana” more quickly than the word “television,” because we associate bananas with their color.

Teachers are often told to structure their lessons into three stages: tell the students what the lesson will be (the priming effect), teach the lesson, and then finally tell the students what they have just been taught (see the recency bias).
What is primacy bias?: Primacy bias, or the primacy effect, is a cognitive bias (a type of mental shortcut) that gives undue prominence to information we receive early in a process (e.g., we are more likely to remember information from the beginning of a presentation than from the middle).

These mental shortcuts (also called “heuristics”) make it possible for our brains to function despite the possibly overwhelming volume of data and stimuli they have to process.

Most of the time, these heuristics work well and allow us to function. At times, though, they can introduce biases that then affect our decision-making negatively.
When does anchoring bias occur?: Anchoring bias can occur, for example, in salary negotiations or bargaining for goods such as a used car. Seeing vehicles that are out of our price range might provide a high anchor point that makes cheaper cars seem like good value, even if they are overpriced.

Anchoring bias is seen in marketing all the time with products stated as being “worth hundreds of dollars” but being offered for “only” a much cheaper price. The initial anchor of “hundreds of dollars” makes $39.99 seem like good value.
What is anchoring and adjustment bias?: Anchoring and adjustment bias is a heuristic (mental shortcut) we use to estimate the answer to a general knowledge question. The anchor element is an initial educated guess, and it tends to limit how much we adjust our answers.

For example, if asked to estimate how long one billion seconds is, most people will underestimate the difference between one million and one billion (even though we know a billion is one thousand million).

So even if we know that a million seconds is equal to 12 days, few will correctly estimate a billion seconds correctly at 31 years.
Is there a difference between anchoring bias and availability bias?: The difference between anchoring bias and availability bias is that the former is a response to external or internal anchors that work as a starting point for estimates we form, whereas the latter favors the most recently available data.

Availability bias describes when a recent event (e.g., a plane crash) affects our assessment of how safe air travel is, because it is recent and well-publicized.

Anchoring bias can be seen in situations like purchasing a car. When we are offered, for example, a car for $20,000 that we can’t afford, that figure becomes an anchor, and a subsequent car priced at $15,000 seems cheap (even if it is objectively overpriced).
Is self-serving bias a problem?: Self-serving bias is a problem for us because it hampers improvement and growth. Instead of an honest reflection and appraisal of why things have gone well or badly, we blame outside forces for our own shortcomings.
What are some examples of self-serving bias in real life?: Self-serving bias is quite easily observed in real life. For example, if I am late for work, I might easily blame the traffic, a slow driver I was stuck behind, or having to wait for a passenger. If I am on time, I might congratulate myself for planning ahead and taking account of possible hold-ups. In both cases, my self-esteem is preserved.

The old saying “a bad workman always blames his tools” is another way of stating at least part of the self-serving bias. The other part is taking credit when things go well.
What is the difference between actor-observer bias and self-serving bias?: Both actor-observer bias and self-serving bias are types of cognitive bias. Although they both help to explain our behavior, they are quite distinct.

Self-serving bias explains how we analyze the way we have behaved, depending on whether the outcome is positive or negative. For example, if we perform well in an examination, we are likely to credit ourselves, whereas if we perform badly, we will criticize the questions, our health, or other external factors.

Actor-observer bias describes how we attribute the cause of undesirable behavior in others to their own characteristics and our own undesirable behavior to external factors. If we (the actor) are late for a meeting, we might blame the traffic or other drivers, but if someone else is late, we (the observer) blame their lack of planning or foresight.
What are some examples of the availability heuristic in everyday life?: If we cancel a planned flight because of a recent air disaster, we are demonstrating the availability heuristic. Air travel hasn’t suddenly become more dangerous (in fact, the opposite is likely to be true), but our perception of its dangers has changed.

Panic buying can be partly explained by the availability heuristic. Media coverage of panic buying can make us believe that we need to stock up on items that, in reality, we have no shortage of.
What causes unconscious bias?: Unconscious bias is caused by several factors:

Socialization: Cultural norms and societal expectations shape our perceptions and behaviors from a young age.

Cognitive shortcuts: The brain uses heuristics to quickly process information, leading to snap judgments and stereotypes.

Past exposure: Personal experiences and exposure to stereotypes influence our attitudes and assumptions about others.

Media influence: Media portrayals can reinforce biases in obvious and subtle ways.

Group identity: Affinity for people who share similar characteristics or backgrounds can lead to in-group favoritism.

Cultural influences that promote unconscious bias are often subtle, yet pervasive (e.g., the color black being associated symbolically with evil).
What are some examples of heuristics in psychology?: There are quite a few examples of heuristics (mental shortcuts) in psychology. The availability heuristic describes how information that is more easily available to us can have a disproportionate effect on our decisions.

The representativeness heuristic leads us to believe the probability of something based on stereotypes that we carry in our minds.
What is the best way to avoid a self-fulfilling prophecy?: Like all cognitive biases, self-fulfilling prophecies can be hard to avoid, especially because they operate at the unconscious level. There are some steps, however, that can help you avoid them:

Recognize self-fulfilling prophecies in your thoughts. It is worth taking time to analyze your thought patterns and the negative thoughts and beliefs you hold about yourself. Recognizing them allows you to take steps to alter them.

Rephrase and reframe your language. Damning yourself with absolute negative thoughts like “I can’t” or “never” feeds into negative self-fulfilling prophecies. Instead, use positive phrases (e.g., “I will try,” “I’ll give it a go”).

Change your mindset to a growth mindset. Recognize that your abilities and talents are not fixed in time, but can all improve. Celebrate each positive step you make to help create positive self-fulfilling prophecies.
Which example best describes the representativeness heuristic?: A good example of the representativeness heuristic is a juror deciding that a person is not guilty of a crime because their appearance is very smart and ordinary. The person’s appearance does not match the juror’s perception of an “average” criminal.
Why is the representativeness heuristic a problem?: The representativeness heuristic directs our focus toward superficial similarities between people and scenarios and can therefore lead to stereotyping.

Basing decisions on our stereotypes of a person’s ethnic identity, profession, or gender can lead to discrimination and bias.
What causes the placebo effect?: The placebo effect is most likely attributable to a number of causes, although no one is certain what the definitive explanation might be. Some explanations for the causes of the effect include:

The power of suggestion

Classical conditioning

The doctor–patient relationship

Research into the placebo effect is always developing and throwing new light on the phenomenon.
What is myside bias?: Myside bias is very similar to confirmation bias (a subtype of cognitive bias), and some people use the terms interchangeably. In its specific meaning, it refers to our tendency to process information in ways that emphasize our existing beliefs. It is particularly prevalent in politics, but can also be seen in sports.

For example, a possible infraction in a soccer game will be seen as an obvious foul by one group of fans, but not by the other group of fans.
What are signs of cognitive bias?: Cognitive bias is very difficult to spot in our own thinking, but there are some things to watch out for if we want to maintain intellectual integrity.

Try not to filter out information that doesn’t align with our existing beliefs, because that can lead to our missing vital evidence.

Be aware of when the initial information we receive can color our assessment of subsequent data.

Try to be aware of our own stereotypical views to guard against confirmation bias.
What is attention bias?: Attention bias is a cognitive bias that affects how we perceive the world around us. We cannot process all the information our senses provide us with, so we filter them out.

Attention bias can have positive and negative impacts. For example, when hiking in the wilderness, we might be more attuned to spotting snakes or other dangerous wildlife.

On the other hand, if we are on a diet, we might find ourselves drawn to the dessert section of the menu at a restaurant.
What is the difference between explicit and unconscious bias?: Both explicit bias and unconscious bias involve prejudiced attitudes that can lead to discriminatory actions and decisions.

They differ in a few essential respects:

Explicit bias: Conscious, deliberate, and openly expressed prejudice

Unconscious bias: Automatic, involuntary, and not consciously recognized prejudice

When people claim to be unbiased, they typically have explicit biases in mind, unaware that they have unconscious biases.
What effects does unconscious bias have in the workplace?: Unconscious bias can have several adverse effects in the workplace:

Hiring and promotion: Bias can lead to unfair hiring practices and hinder the promotion of qualified individuals.

Employee morale: Perceived unfair treatment can decrease job satisfaction and morale among employees.

Workplace diversity: Bias can result in a lack of diversity, limiting different perspectives and ideas.

Performance evaluations: Bias can affect the objectivity of performance reviews, leading to inequitable evaluations.

Team dynamics: Bias can create divisions within teams, reducing collaboration and productivity.

Turnover rates: Unaddressed bias can increase turnover, as employees may leave due to perceived or actual discrimination.

Legal risks: Bias can lead to legal issues related to discrimination and harassment claims.

Reputation: A workplace perceived as biased can damage an organization’s reputation and ability to attract talent.

These can be mitigated by raising awareness through strategies like implicit bias testing, setting objective criteria for performance reviews, and adopting blind hiring processes.