How to find Class C respondents for research
18 min read
If you work with market research, you probably already know that Brazil is, to a large extent, driven by Class C. We are talking about a group that represents more than half of the population and is the true engine of our economy.
But when it comes to putting a survey into the field, the challenge arises: how to find and engage Class C respondents efficiently, without bias, and with reliable data?
That's exactly what we're going to talk about today. If you want to understand what characterizes this audience, how to recruit them, what incentives really work, and how to avoid those fraudulent responses that give any researcher a headache, pull up a chair. Let's dive deep into this universe.
What characterizes a Class C respondent?
Before sending out questionnaires, we need to understand who we are talking to. After all, what makes someone considered “Class C” in Brazil today?
If you look at data from Critério Brasil (ABEP) or FGV Social, Class C encompasses families with a monthly income broadly ranging between R2.500 and R2.500 and R2.500 – 10.800.
But limiting Class C to just a paycheck is a strategic mistake. Today, Class C is much more about behavior, aspirations, and connectivity.
This portion of the population has grown significantly in recent years. Between 2022 and 2024 alone, more than 17 million Brazilians moved up to classes A, B, and C, driven by labor income and social programs.
And who is this “new Class C”? It's a hyperconnected generation. They own the internet in Brazil. More than 90% of consumers in this income bracket who buy on marketplaces have a strong affinity for digital channels. They use smartphones all day, are on social media, have digital bank accounts, and consume streaming.
Therefore, a Class C respondent is not someone disconnected or technologically difficult to access. On the contrary: they are online, selective, seek cost-benefit, and value their own effort. When answering a survey, they want to be heard, but they also want to feel that their time is being valued.
Consumption behavior and research with Class C
For a market research to be truly effective, it's not enough to just know how to recruit. It's necessary to delve into the consumer psychology of this audience. The Brazilian Class C has experienced economic ups and downs in recent decades. They lived through the credit boom of the 2000s, subsequent economic crises, and, more recently, the recovery of purchasing power combined with accelerated digitalization due to the pandemic.
All of this shaped an extremely rational consumer, but one who does not give up small indulgences. When you design a questionnaire to understand the acceptance of a new product by this audience, you need to consider that the “price” variable will almost always be accompanied by the “durability” or “yield” variable.
The relationship with brands and products
Contrary to what common sense often preaches, Class C is highly loyal to brands that deliver on their promises. If a cleaning product from brand X costs a little more, but the housewife realizes that it yields twice as much as the cheaper competitor, she will do the mental math and opt for product X.
Therefore, in your online surveys, when testing concepts or packaging, include questions that explore “perceived value” and not just “absolute price”.
Questions like “How long do you think this product will last in your home?” or “Would you consider that this product replaces the purchase of two other items?” usually generate rich insights that go far beyond a simple “expensive or cheap.”
The omnichannel purchase journey
Another fascinating aspect that should be mapped in your research is the purchase journey. Class C is a master of what we call the phygital (physical + digital) journey.
It is very common for this consumer to exhaustively research an appliance on their smartphone, read reviews on social media, watch videos on YouTube, and, in the end, go to the physical store just to close the deal and leave with the product in hand (saving on shipping).
If your research tries to understand sales channels, make sure not to create mutually exclusive questions that do not reflect this reality. Allow the respondent to select multiple options and create logical paths in the questionnaire that investigate the reason for choosing each channel at different moments of the journey.
How to find Class C respondents for surveys?
Finding Class C is not looking for a needle in a haystack, as they are the majority. The challenge is to find them at the right time and with the right disposition to participate in your study.
Historically, recruitment happened on the streets or by phone (CATI). But today, with the massive digitalization of this audience, the best way to find them is where they already spend most of their time: on the internet and on smartphones.
The most efficient approach today is the use of online respondent panels. These panels gather thousands (sometimes millions) of people who have voluntarily registered to participate in surveys. Since registration requires filling in detailed socioeconomic data, you can filter exactly who is from Class C, from which region of the country, what their age is, and even their consumption habits.
In addition to panels, social media (Facebook, Instagram, WhatsApp) are also great channels for recruitment, but require extra care with screening to ensure that the profile matches Class C and not curious people from other classes.
Does online research work well with Class C?
The short answer is: yes, it works very well. The long answer is: it works, as long as you adapt the research to their reality. As we've seen, Class C is highly digitized. However, the main means of internet access for this audience is the smartphone, often using mobile networks (3G/4G/5G) with limited data packages or Wi-Fi at home.
This means that your online research must, obligatorily, be mobile-friendly. If the questionnaire is heavy, full of images that take a long time to load, or with formatting that breaks on the cell phone screen, the abandonment rate will skyrocket.
Another point is the language. Online surveys with Class C work better when the tone is clear, direct, and close to everyday life. Avoid corporate or academic jargon. If the survey is easy to access, quick to load, and simple to understand, Class C responds in full and with excellent data quality.
Which channels generate the highest recruitment rate?
When we talk about channels for recruiting Class C, we need to think about where their attention is concentrated. The channels that generate the most conversion for surveys with this audience are:
Survey panel apps
Having an app on the respondent's cell phone, where they receive push notifications about new surveys, is the channel with the highest response rate. The person is already engaged and ready to participate.
The messaging app is almost unanimous in Brazil. Sending survey invitations via WhatsApp (when authorized by the user, of course) has a very high open and conversion rate, due to convenience and familiarity.
It still works well, especially for structured panels, but it competes with a lot of clutter in the inbox. The open rate is usually lower than WhatsApp, but it is an important complementary channel.
Social Media (Ads)
Targeted ads on Facebook and Instagram can attract new respondents, but the cost of acquisition (CAC) can be higher and the screening process needs to be rigorous to prevent people outside the profile from entering the database.
For Class C, smartphone convenience is key. Channels that deliver the survey link directly to the palm of their hand, such as apps and WhatsApp, are the champions.
How to increase the participation of this audience?
You launched the survey, but the responses are trickling in slowly? This is common. To increase Class C participation, you need to pull some levers:
Questionnaire length
Time is precious for everyone, but especially for those with an intense work routine. Questionnaires longer than 10 to 15 minutes tend to have high abandonment rates. Be objective. Get straight to the point. If the study is long, consider dividing it into modules.
Accessible language
Speak the respondent's language. If the question is confusing or uses terms they don't understand, they will simply close the tab or, worse, guess an answer that will compromise your data.
Responsive design
We've talked about this, but it's worth repeating. It has to work perfectly on mobile. Test the questionnaire on different screen sizes before sending it out.
Transparency
Make it clear from the beginning how long the survey will take and what the general objective is (without revealing the sponsor if it's a blind study, of course). When the respondent knows what to expect, they are more committed.
Incentives
The icing on the cake. Rewarding the respondent for their time is fundamental, and we will detail this in the next sections.
How to avoid biases in recruitment?
Bias is the great villain of any researcher. If you recruit poorly, your data does not reflect reality. When researching Class C, some biases are common and need to be avoided:
Self-selection bias
Occurs when only people very interested in the topic (or the incentive) respond. To avoid this, do not reveal the central theme of the research in the invitation. Use generic descriptions like “Research on consumption habits” instead of “Research on brand X soda.”
Channel bias
If you only recruit through Instagram, you will get a younger and more visual Class C. If you only use email, you might get a slightly older or more formal audience. The ideal is to use panels that diversify recruitment sources and ensure a balanced distribution.
“Professional respondent” bias
That person who participates in 10 surveys a day just for the prizes. Serious panels control the frequency with which the same user can answer surveys to prevent their opinion from having excessive weight in the database. This control is called a “cooling period” (rest period between surveys).
Geographic bias. Class C in the interior of Minas Gerais has different habits from Class C in the periphery of São Paulo. If your study requires national representativeness, ensure that the sample includes all regions and not just large urban centers.
How to ensure a representative sample?
Ensuring representativeness means ensuring that your sample is a mirror of the real population. For Class C, this means looking beyond income.
Class C is not a homogeneous block. There is Class C from the Southeast, Class C from the Northeast, younger people, older people, those who live in capitals and those from the interior. To have a representative sample, you need to establish cross-quotas in your sampling plan.
For example, if IBGE says that X% of Class C is composed of women aged 25 to 34 in the South region, your sample should seek this same proportion.
The use of a robust respondent panel allows the system to block the receipt of responses from a specific profile as soon as its quota is reached, ensuring that the final portrait is faithful to market reality.
Another important point is sample size. For quantitative research with Class C, samples between 400 and 1.000 respondents usually offer a statistically acceptable margin of error (between 3% and 5% with 95% confidence). But the exact number depends on the level of segmentation you intend to do in the analysis.
Do Class C respondents need financial incentives?
Let's be very honest: yes, they do. People participate in surveys for three reasons: to help, because they like the topic, or for a tangible benefit. For Class C, who often have an intense work routine and highly value their own time and effort, asking them to dedicate 15 minutes of their day for free is asking too much.
The incentive is not a “purchase of opinion,” but rather a fair way to remunerate the time the respondent dedicated to generating value for your brand. Studies show that offering incentives significantly increases response rates and engagement.
Furthermore, the incentive helps democratize research. Without it, only people with a lot of free time (retirees, students) would tend to respond, creating a bias in the sample. With the incentive, you also attract the worker who is on their lunch break or on the bus returning home.
What is the ideal reward value?
There is no magic value, but there is common sense. The reward value should be proportional to the effort required.
If it's a quick 5-minute survey, a micro-incentive (like points that accumulate for a future redemption) works well. If it's an in-depth (qualitative) interview that will last 1 hour by video, the reward needs to be substantial (50, 100 or more, depending on the profile and complexity of the topic).
For quantitative online surveys with Class C, the most sustainable model is the scoring system. The respondent earns points for each completed survey. When they reach a limit, they exchange them for money or prizes. This maintains long-term engagement without inflating the cost of each interview.
The important thing is that the incentive is not so low as to be ignored, nor so high as to attract fraudsters or people who will answer anything just for the money. The balance is in offering something that the respondent perceives as fair for the time invested.
Which incentives are best accepted?
When we talk about Class C, practicality and utility speak louder. The incentives that have the best acceptance are:
- Direct cash to account
Pix transfers are absolute favorites. Money gives people the freedom to use it as they wish, and Pix has made it instant and hassle-free.
- Gift Cards
Vouchers for supermarkets, department stores, iFood, Uber, or cell phone top-ups are extremely popular because they quickly convert into savings in the household budget.
- Cell phone top-up
As a significant portion of Class C uses prepaid plans, earning cell phone credits in exchange for answering a survey is a high perceived value incentive. The cost to the company is low, but the benefit to the respondent is immediate.
Sweepstakes (e.g., “answer and compete for an iPhone”) tend to have much lower acceptance than guaranteed rewards, even if of low value. Class C prefers the “little certain” over the “very doubtful.”
This makes perfect sense when you understand that this audience deals with their budget pragmatically and prefers concrete and immediate benefits.
How to ensure reliable responses?
This is the Achilles' heel for many people. How do you know if the respondent didn't just click on the first option to get to the end and get the incentive? To ensure data quality, you need control mechanisms within the questionnaire itself:
Trap Questions
Insert a question in the middle of the questionnaire saying: “To show that you are reading carefully, please select the option ‘Blue'”. Anyone who clicks on another option is disqualified. This technique is simple but extremely effective.
Time control (Speeders)
If the average response time is 10 minutes and someone finished in 1 and a half minutes, that person did not read the questions. The system should automatically invalidate that response. Most survey platforms allow you to configure an acceptable minimum time.
Straightliners
In matrix questions (that grid of options), if the respondent marked the same column for all rows from top to bottom, it is a strong indication of inattention. Quality algorithms detect this pattern and flag the response for review.
Open-ended questions
Asking the person to write a short sentence about a topic helps identify if there's a real human there or if the answers are nonsensical. Responses like "asdfgh" or texts copied from the internet are clear signs of fraud.
Logical consistency
If the respondent says they are 22 years old in one question and then states they have 3 adult children in another, something doesn't add up. Cross-referencing information throughout the questionnaire is an extra layer of protection.
How to identify fraudulent responses?
In addition to questionnaire controls, the technology of the panel you use is fundamental to preventing fraud even before it happens.
Fraudulent responses usually come from bots (robots programmed to answer surveys) or from people using VPNs and multiple accounts. To identify and block these, good panels use:
- IP Verification and Geofencing
To ensure the respondent is actually in Brazil and in the region they claim to be. If someone claims to live in Recife, but their IP points to another country, the response is discarded.
- Device Fingerprinting
Identifies the device (mobile/computer) to prevent the same person from creating multiple accounts and answering the survey multiple times. Each device has a unique "digital fingerprint."
- Identity validation
Serious panels require email confirmation, cell phone (SMS) verification, and even data cross-referencing with public databases to ensure the CPF matches the name and date of birth.
- Captchas and reCAPTCHA
Those "click on the traffic lights" or "drag the slider" tests help block robots right at the entrance of the questionnaire.
- Behavioral analysis with AI
Advanced systems monitor click patterns, typing speed, and cursor movement to distinguish humans from bots with high accuracy.
5 mistakes when researching with Class C
To summarize what not to do, here are the 5 most common mistakes when researching this audience:
Ignoring mobile
Creating questionnaires that only work well on a computer screen. Class C will open it on their cell phone, the layout will break, and they will abandon it. Result: plummeting completion rates and a sample biased towards those with desktop access (usually at work).
Flowery language
Using technical terms, unexplained acronyms, or overly complex questions. If the respondent doesn't understand, they will guess an answer, and you will make business decisions based on guesses. Not good.
Endless questionnaires
Thinking that people will spend 30 minutes answering an online survey. The ideal is not to exceed 10 to 15 minutes. If the study requires more time, divide it into waves or modules and reward proportionally.
Lack of clear incentive
Not valuing the respondent's time or offering sweepstakes that don't generate real engagement. Class C needs to see concrete and immediate value in participating.
Not using quotas
Sending the link to a general database and accepting the first 500 responses that arrive. You run the risk of having 80% women from the Southeast and thinking that this represents all of Brazil. Without quotas, there is no representativeness.
How to structure a questionnaire for Class C
The structure of your questionnaire is the bridge between your business question and the consumer's mind. If this bridge is fragile, communication won't happen. Let's detail the best practices for building questionnaires focused on this audience:
The Warm-up (Icebreaker)
Never start a survey with the most difficult or sensitive questions (such as exact income or debt details). Start with easy, multiple-choice questions about general habits. This helps the respondent get familiar with the interface and reduces initial anxiety.
The "Less is More" Rule
If you present a question with 15 answer options on a cell phone screen, the respondent will have to scroll multiple times. This increases cognitive fatigue. If you need many options, try to categorize them or use display logic where secondary options only appear depending on the main answer.
Be careful with overly complex scales
Researchers love 7 or 10-point Likert Scales. However, for the general public, and especially on small screens, 5-point scales (Strongly Disagree, Disagree, Neutral, Agree, Strongly Agree) are much more efficient and generate data with less room for confusion.
The strategic use of images and videos
Since Class C consumes a lot of visual content, using images in the questionnaire is an excellent tactic. If you want to know the preference for a type of packaging, show a photo. But be careful: optimize the size of these images. A 5MB photo will crash the respondent's 4G, and they will close the survey. Compressed images, in the range of 100kb to 200kb, are ideal.
Meet PainelTAP: The solution for research with Class C
Conducting market research with Class C requires strategy, technology, and, above all, access to a qualified base. Trying to recruit this audience from scratch for each project is expensive, time-consuming, and risky. This is where the importance of having a specialized partner comes in.
If you need a reliable, segmented sample ready to respond to your studies, PainelTAP is the ideal solution.
PainelTAP has a robust base of over 19 million registered and verified people. We connect your research to real people, combining qualified audience, technology, and artificial intelligence to transform questions into strategic decisions.
With PainelTAP, you have access to:
- B2C Consumer Panel: Diversity of profiles from classes A, B, C, and D, ensuring a truly representative sample of the Brazilian market.
- Security and quality: Rigorous identity validation processes and fraud protection, with LGPD and Cyber certifications.
- Agility: You don't have to worry about recruitment. They handle questionnaire programming, distribution, quota control, and delivery of clean and tabulated data [6].
- AI Analysis: The AnáliseTAP platform allows you to cross-reference data, generate reports, and even create presentations in minutes using Artificial Intelligence.
PainelTAP understands the behavior of the Brazilian respondent and knows how to engage Class C ethically and efficiently, ensuring that your insights are based on real and reliable data. Companies like Nubank, Heineken, Smart Fit, and Getnet already conduct research with them.
Don't waste time trying to find a needle in a haystack. Let the technology and expertise of those who understand the subject work for your project.
Ready to put your research into the field with the right sample? Discover PainelTAP and ensure the success of your next market study.