You spend your time, energy, and resources on a survey to understand your audience better.  But what if a significant number of people don't respond to it? This is called non response bias, a type of bias in surveys. 

Research findings suggest that response rates falling below 70% critically impact the results of surveys. 

You don’t want that to happen to your surveys, right?

In this article, I'll dish out some practical tips to avoid non response bias in surveys. 

But before diving into it, let's quickly review what non response bias is and why it happens.

What is non response bias?

Non response bias is an error in surveying that occurs when less than 70% of the people who are asked to participate in a survey don't actually respond.

Now, why is this a problem? Well, think about it. 

If an insufficient number of your sample completes the survey, you might not have enough data to analyze and draw conclusions. 

For example, imagine I'm conducting a survey to gauge public opinion on climate change, and only 60% of people respond. 

Out of these, 20% believe climate change is a critical issue, while 40% are indifferent. 

With 40% of the total survey population not responding at all, it's challenging to accurately determine overall public sentiment. 

How can I confidently draw conclusions when such a significant portion of the sample remains silent?

Survey data is most informative when you can see the complete picture, so limiting non response bias impacts both your survey responses and decision making. 

Non response bias can sneak into surveys in all sorts of ways. Some people may be too busy or just not interested in taking your survey. 

Some may not check their email often enough to see your invitation. It could even be that they're hesitant to share their thoughts on certain topics, so they avoid the survey altogether.

A non response bias example would be you sending a survey to your past customers from many years back without updating the email list. Many may no longer access those inboxes. 

Or, if you ask about sensitive topics like tax compliance, citizens who don't properly follow tax laws will be more likely to refuse, and your data will be biased towards a more law-abiding sample.

Whatever the reason, the result is an inaccurate view of what people really think. And that can lead to decisions based on incomplete or skewed information.

Here are some detailed reasons that cause non response bias in surveys.

What causes non response bias in surveys?

People may choose not to respond to your surveys because of the following: 

Survey fatigue

We're bombarded with surveys these days – online, emails, over the phone, even on our receipts.

It's no wonder people get tired of answering questions. Survey fatigue is real and can lead to people ignoring your survey altogether.

If a survey is too long or repetitive, people are more likely to click "exit" than give thoughtful answers. 

Failed deliveries

Sometimes, technology throws a wrench in the works. Emails might land in spam folders, phone calls go unanswered, or online surveys glitch out. 

If your survey doesn't reach your target audience, you will see a non response bias. 

Refusals

Some people just don't feel like answering surveys, plain and simple. 

They might be busy, find the topic uninteresting, or simply dislike the idea of sharing their opinions.

While you can't prevent all refusals, making the survey quick and worthwhile can encourage more people to say yes to filling it. 

Requesting sensitive information

Surveys that touch upon personal finances, health issues, or political beliefs can make people uncomfortable. 

If your survey touches on sensitive topics, some folks might choose to stay silent rather than reveal private information.

Accidental omission

Have you ever got so caught up in your to-do list that you forgot something important? It happens to the best of us. 

Sometimes, people mean to respond to a survey, but then life gets in the way. 

Maybe they meant to do it later, but totally spaced out. 

So, it's not that they don't want to participate; they simply forget about it. 

We looked at the reasons why people might skip out on your survey. Now, let's get tactical.

What are some solutions to nonresponse bias?

Here are some ways that explain how to avoid non response bias and improve survey response rate. 

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Improve survey design

When it comes to getting more responses and reducing bias, the design of your survey is crucial. 

‍Biased survey questions are a surefire way to lose respondents. 

• Use simple, easy-to-understand language and keep it under 5 minutes. 

• Avoid jargon or technical terms your audience might not know. 

• Structure questions logically, and preface them with clear introductions that set the context.

Instead of asking "On a scale of 1 to 10, how satisfied were you with the various functionalities of our new website?", break it down. 

Ask specific questions like "Were you able to find the product you were looking for?" or "Did you encounter any difficulty during the checkout process?" and so on. 

Let people know what to expect from the get-go. 

Briefly explain the purpose of the survey and how long it will take to complete. 

For example, you could say, "This survey will take approximately 5 minutes to complete and ask about your shopping habits.".

Send friendly reminders

Life gets busy, and sometimes, your survey might get buried under a pile of emails. 

Sending friendly reminders can jog people's memory and encourage them to complete it.

Send reminders at strategic intervals. You don't want to bug people too soon and come off as pushy. 

But you also don't want to wait so long that they've completely forgotten about your survey. 

Wait a few days after the initial invite before sending a reminder.

Here’s a simple reminder email template you could use: 

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Subject: Just a friendly reminder: Your feedback matters!

Hi [Name],

We hope you saw our survey about your recent experience with our customer service team. Your input is crucial in helping us improve, and the survey only takes 5 minutes!

Click here to share your thoughts: [Survey Link]

Thanks, 

The [Your Company Name] Team

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Use multiple distribution channels

People have different preferences for how they interact with surveys. 

Don't limit yourself to just email. 

Here are some ways to reach your target audience where they are:

• Social media: Share your survey on your company's social media pages or relevant online communities.
• Website pop-ups: Consider a quick, non-intrusive pop-up on your website inviting visitors to participate.
• QR codes: Print QR codes on flyers, posters, or business cards. People can scan the code with their smartphones to access the survey directly.
• Mobile apps: If you have a mobile app, integrate the survey directly within it for a seamless experience.

Different channels call for different approaches. 

What works in an email might not work on social media. 

So, make sure to tailor your message and tone to fit each platform. 

For example, keep it short and snappy for social media, but a tad more formal for email.

Monitor survey deliveries

Keep an eye on the number of emails that bounce back due to invalid or incorrect email addresses. 

If you notice a high bounce rate, it's a good idea to clean up your email list and remove any invalid addresses.

Monitor the open and click-through rates of your survey emails. 

A low open rate may indicate that your subject line or sender name is not compelling enough, while a low click-through rate could mean that your email content needs improvement.

Nobody likes finding important emails stuck in their spam folder. 

Make sure your surveys aren't getting marked as spam by email filters. 

Double-check your subject lines and content to make sure they're not triggering any red flags. 

A survey tool, such as Formaloo, can help you ensure that your surveys are reaching the right people at the right time.

Offer incentives

Who doesn't love a little something extra? Incentives can be a great way to motivate people to take the time to fill out your survey.

Think about what would motivate your target audience. It could be anything from a discount on your products or services to a chance to win a gift card or prize. 

Just make sure it's something that's valuable and relevant to them.

Let people know right up front what's in it for them. Include details about the incentive in your survey invitation or reminder emails. 

The clearer you make it, the more enticing it'll be.

Create a sense of urgency by setting a deadline for when people need to complete the survey to get the incentive.

Close the feedback loop

One of the biggest complaints about surveys is feeling like your answers go into a black hole. 

Closing the feedback loop means showing people you heard their input and will take action based on their responses.

A little gratitude goes a long way. 

Take the time to send a thank you email to participants for their input. 

Let them know that their opinions matter and that you appreciate them taking the time to share their thoughts with you. 

It's a small gesture, but it can make a big difference.

Once your survey is over and you've crunched the numbers, don't keep the results to yourself. 

Share them with your participants! 

Let them know what you've learned from their responses and any changes you're planning to make as a result. Transparency is key here.

Non response bias Vs response bias

A lot of people also get confused between nonresponse bias vs. response bias. 

Non response bias occurs when certain groups of people do not respond to a survey. It stems from people’s choice to not respond to a survey and leads to a lack of representation in the data. 

Non response bias affects the completeness and representativeness of the data by excluding certain groups from the sample.

Response bias, on the other hand, happens when respondents provide inaccurate or false answers to survey questions. 

It is caused by people giving incorrect or insincere answers, which results in skewed results. 

This type of bias in surveys impacts the accuracy and reliability of the data by introducing inaccuracies in the responses provided.

Create surveys that people can’t resist taking!

Tackling non response bias or other types of bias in surveys takes some savvy moves and attention to detail. 

But here's the best part: you don't have to do it alone. 

Formaloo is an intuitive survey maker with an easy-to-use drag-and-drop interface that helps you design engaging surveys from scratch. 

There are also tons of ready-to-use Formaloo templates that make the process super quick. 

Plus, there are features like question branching, progress indicators, and mobile-friendly design that make the survey engaging. 

Sign up for Formaloo’s free trial today and make bias-free surveys that your audience can’t resist taking.