Understanding acquiescence bias: What it is and how to avoid it

Many factors can affect how survey respondents answer or engage with your surveys. These factors can muddle your results until there’s too much noise and no clear direction to guide future improvements.

When collecting survey-based feedback, you need to stop that noise in its tracks. That means curtailing any potentially confusing elements that obscure your respondents’ real opinions.

One potential source of bias is acquiescence bias—a problem that can make respondents so agreeable and passive you can’t detect their true opinions. 

Acquiescence bias can shape any survey, and it’s hard to “zero out” or account for its influence once it’s present. The only way to eliminate it is before sending your survey out.

This guide will illustrate the common ways acquiescence bias can enter your survey and strategies, showing you how to eliminate it before your next research project. Removing its influence can significantly—and immediately—give you more clarity.

At its core, acquiescence bias is the tendency to agree with something even when you don’t.

To some degree, acquiescence bias can be inherent within certain people—those who are highly agreeable, passive, or simply don’t want to engage. Some activities also invite acquiescence; for example, unpleasant encounters where agreeing shortens the interaction but has no real ramifications on the person.

However, a lot of acquiescence bias is circumstantial. Your survey can invite it with poorly worded questions, narrow answer options, and badly presented invitations to participate. Everything from an unwelcoming format to pushy language strengthens acquiescence bias and clouds survey results with the feedback your research team wants to hear.

Why is acquiescence bias a problem?

Acquiescence bias is problematic in surveys and interviews because it makes the feedback results untrustworthy—to a virtually unknowable degree. Did survey respondents agree that a pop-up form on your website was helpful because it truly provided value or because you asked, “How helpful was the pop-up?” with a 1–5 scale where answering “1” felt rude?

Depending on your objective when gathering research, acquiescence bias can have severe downstream implications:

• You might invest in features, services, and products your target market doesn’t care about.

• Your team might invest significant time and resources in making changes your users won’t like or benefit from.

• Ideation-stage projects may go off in the wrong direction based on initial feedback.

• Different research teams find contradictory results, leading to internal frustrations and less buy-in on important projects.

• Surveys that invite acquiescence bias can hurt your relationship with the respondents. They might think you’re pushing for specific answers or find the experience unenjoyable.

Proactively addressing these sources of noise can lead to a much more enjoyable experience for your respondents and better insights for your team.

What is acquiescence bias vs. social desirability bias?

Acquiescence bias and social desirability bias heavily overlap, but they don’t always manifest in the same way or come from the same place.

Respondents susceptible to social desirability bias are more likely to answer questions according to what they think will elevate their social status or make others like them. For example, they might agree with other respondents or give answers that make them appear smart or funny. In individual surveys, they might even give critical answers to receive offers or discounts.

It’s important to construct your survey to minimize the effects of social desirability bias from the outset. 

Acquiescence bias is also frequently called “yes bias” because it generally pushes respondents to give affirmative answers. In yes/no-style questions, acquiescent participants will simply answer “yes” unless the question very strongly implies a negative construction.

Another way to identify acquiescent responses is by gauging whether a specific answer feels like the right answer. For example:

• “Is it easy to make a purchase?” As a yes/no question, this clearly requests a “yes” answer. Not only does the question lead respondents to that answer, but few people want to admit something is hard for them.

• “How easy is it to make a purchase?” This question presupposes that the process is easy and maybe even implies that everyone finds it easy to some extent. Respondents may feel pressured to agree with those assumptions.

• “What would make purchasing easier?” This doesn’t implicitly push for one specific answer but is inconvenient and requires critical thinking. Respondents may reply that the process is simple just to get past the question.

The examples above demonstrate three common causes of acquiescence bias:

1. Researcher bias

2. Desire to please

3. Lack of motivation

However, there are eight core causes your team should proactively mitigate. Let’s look at them in detail below.

Researcher bias

Researchers must be particularly vigilant about showcasing what answers they want or simply expect from a specific question. Using trigger words like “easy,” “hard,” and “annoying” sway the respondent and demonstrate a default expectation.

It’s not just wording, either. Multiple questions around one specific detail tell respondents that the detail is important to you. The color of the buttons on an online survey impacts which answers people tap. Even the question format can influence answers if it introduces too much drag or requires too much work.

Desire to please

Some people are simply agreeable and want to please who they are speaking with. If they like your brand or you build a rapport with them in an interview, they’ll agree with what you say because they prioritize the relationship.

You can reduce this bias by strongly encouraging truthful answers, even if they are negative. You can also scrub implicit cues from the questions so that agreeable respondents don’t just default to the “right” answer.

Lack of motivation to engage

Many people simply don’t want to give feedback. They might not want to complete the survey at all and may be participating just to get a reward. Some respondents may want to stop once the questions take time to answer.

You can often resolve this by making the questions simple, asking just a few questions (and telling people how many there are at the outset), and offering an easy opt-out so you only get motivated respondents.

Social desirability

Remember, social desirability bias and acquiescence bias overlap. If you have a group interview session or a situation where respondents can extrapolate the general opinions of their peer group, this will impact their answers. They can give almost any type of answer—shorter answers, pithy answers, answers that benefit the group even if they don’t believe it themselves—and cloud what really motivates their individual behaviors.

Cognitive fatigue

Carefully design your surveys so that they don’t feel tiresome. Apathetic respondents may click through the survey quickly in a bid to get on and finish it. Respondents motivated by an external reward like a discount code might do the same thing.

Even eager respondents who advocate for your brand and products may start feeling fatigued if there are too many questions or they don’t know how much longer the survey is going to last.

Survey designers can reduce these challenges by keeping surveys short, informing respondents of the average time to completion, and clearly displaying progress on every screen. Telling the respondents how many questions the survey contains beforehand can also help.

Ambiguous questions

Acquiescence bias isn’t solely caused by your respondents’ temperament or mindset. The survey itself often plays a role.

Be wary of ambiguous questions. If there’s room for confusion or misinterpretation, respondents may veer toward the answers they think you want them to give. Their agreeability will disguise the confusing questions and lead to incorrect assumptions on both sides.

The participant’s perception of their ideal self

Depending on the survey’s subject matter, respondents may answer from their perspective of their idealized selves rather than their authentic selves.

For example, imagine you’re asking participants about their activity levels. Many respondents will over-inflate the numbers. They might do this because they desire to be more active or see more virtue in being active.

This same dynamic can impact purchasing questions, lifestyle questions, and demographic questions.

Background influences

The noise of background influence isn’t unique to acquiescence bias. You can’t control for every respondent’s background, and their different backgrounds might shape research-based initiatives.

Socioeconomic background, education level, gender, and occupation all impact how people respond to questions. Even the time of day, the noise level in the room, and their to-do list—the background of the survey experience—can influence their responses.

Uncontrolled acquiescence bias makes the results you receive from a survey false. More than that, it’s hard to guess how they’re untrue, what information is false, and what conclusions are untrustworthy.

If you realize a survey is too susceptible to acquiescence bias early on, you can halt the project and revise the questions. However, this will result in time delays and possibly expenses.

For many organizations and research groups, acquiescence bias is far more likely to go unnoticed. This can have the following impacts on your research:

• Inflated support for an expensive new product or service

• Poor decision-making based on skewed responses

• Follow-up surveys and research based on false premises

• Projects that fail to launch or never recoup their costs

• A poor understanding of your audience’s needs that makes you lose their loyalty or interest over time

These impacts are significantly costly in terms of time, money, and respondent goodwill.

Once you understand what acquiescence bias is and the threat it can pose to research-based projects and initiatives, you can start taking steps to eliminate it. Adopt these strategies now so you can weed triggers out of your questions.

1. Keep surveys short

Engagement and honesty stay high when surveys are short. If your survey is too long or the questions require too much work, respondents will start to give incomplete answers or false answers that help them reach the end.

Besides keeping the survey short, tell respondents which question they are on on every page. For example, tell them when they are on question four out of five so impatience doesn’t creep in.

2. Avoid leading questions

Read through your survey questions to ensure they are objective and neutral.

Leading questions come in many forms. Yes/no questions push for a “yes” in most circumstances, and emotional or descriptive words imply a preferred response. Even certain follow-up questions and ways of phrasing them can clue people in on what answers you want or expect.

3. Use intentional language

Intentional language deliberately considers word choice, how the wording and messaging impact respondents, and how the connotations of different words change for different audiences.

Use language intentionally to focus on neutral terms and create survey questions without ambiguity. Encourage respondents to be honest and authentic—these purposeful reminders can help banish lingering bias from within the language.

4. Allow open-ended responses

Simple, open-ended questions give you more meaningful feedback, even if it’s harder to quantify. You can set up your survey so every survey question allows for open-ended comments, or you can ask for expanded, honest answers.

Take care not to introduce bias in answers with frameworks like, “If you have answered ‘no,’ please explain your reasoning.” This style of question implies that “yes” is the right answer. Answering “no” also requires more effort, making it unappealing.

5. Clarify the survey scale

Survey scales can be confusing. Clarify them with the following tactics:

• Explain whether the low number or high number is the positive answer (and vice versa).

• Give contextual examples of what each number at the end of a scale might mean, such as “strongly agree” or “strongly disagree.” Remember that your wording shouldn’t influence participants.

• Label the scale whenever you use it.

6. Minimize potential confusion

Confusion is distinct from acquiescence response bias. However, if your questions—or the context for asking your questions—are confusing, many respondents will default to being agreeable. They will answer questions based on tone and what causes the least trouble for themselves.

Ask clear, concise, and direct questions. Make sure the questions are easy to read, use commonly understood words, and don’t contain compound structures.

7. Segment your participants

Some of these strategies are hard to implement while still helping you reach your research goals. For example, it can be hard to get all the insights you need if you only ask a minimal number of questions or ask lots of unuseful questions. 

Prevent these problems by segmenting your participants into buckets and giving each bucket a smaller, more relevant survey. This is best practice because it mitigates acquiescence bias, gives you clearer insight into different target markets, and allows you to build custom features or services based on survey responses.

8. Mix different formats

The more question and response formats you use, the less risk there is of unexpected bias.

Ask a mixture of open-ended questions, scaled questions, and multiple-choice questions to gather accurate responses. Even better, if you send multiple surveys to the same audience over time, use different formats for the same concepts. This enables you to analyze the results and pick up on discrepancies and acquiescent response bias that may exist in one format but not another. With these insights, you can make future surveys more objective.

9. Be transparent to manage expectations

Finally, build transparency into the questions and the information around the survey.

You can tell respondents the number of questions upfront and display a countdown on every page. You can also emphasize your goal: authentic answers rather than agreement for agreement’s sake.

Share what the survey is intended to do. For example, if you’re conducting a survey to guide a website redesign, share this information with users. Telling them the survey’s purpose will encourage them to give answers they think will improve their online experience.