For decades, RDD (Random Digit Dialing) was the gold standard for collecting telephone data from the general public for market research purposes.

This is particularly the case in the government and academic space, where many are still leveraging this methodology.

However, with the sharp and continued rise of cell phone usage and sophisticated Caller ID, response rates for RDD dialing have decreased significantly.

As a result, mixed-mode data collection has emerged as a popular alternative to RDD dialing. Not only can mixed-mode improve response rates and geographic coverage, it can also provide a more comprehensive understanding of the research topic.

Mixed-Mode Overview

Mixed-mode data collection involves using multiple methods to collect data from respondents in the geography of interest.

For example, a market research study may use a combination of mail surveys, online surveys, text to web, and telephone interviews to gather data.

This approach allows researchers to contact respondents through multiple channels, increasing the likelihood of obtaining a response.

If we look at each mode for what they offer both the researcher and the respondent, we can decide what combination of modes best suits a particular survey.


A mail survey using ABS (address-based sampling) can offer the best representation of the geographic area in terms of sample coverage.

Mail surveys are convenient for respondents, as they can complete the survey at their own pace and at a time that suits them.

They can also provide anonymity, which can encourage them to provide honest and accurate answers.

Mail survey can reach a wider audience, including those who may not have internet access or who are not comfortable with other survey methods.


Online surveys can be designed to define the geographic area of interest, and allow you to target demographics such as gender, age, and income, for example.

There is also the option of doing text-to-web. Cell phone numbers in the geographic area of interest are sent a short text invitation with a link to the online survey instrument.

Online surveys are cost effective and offer real-time data.


CATI is often used in mixed-mode surveys as the final attempt to gain cooperation in a survey.

Those who did not respond to any of the previous modes would be called to take the survey using a live agent.


The use of mixed-mode data collection has several advantages over RDD dialing. First, it allows researchers to reach a broader range of respondents, including those who may not be available during traditional calling hours.

Second, it allows respondents to choose the method of data collection that is most convenient for them, thereby increasing the likelihood of participation.

Finally, mixed-mode data collection can lead to higher response rates, which can improve the accuracy and reliability of the data collected.

With the availability of software that can easily manage responses through these various data collection channels, it has become easier to avoid bias and discrepancies in the results.


Mixed-mode data collection has emerged as a popular alternative to RDD dialing in market research to improve response rates.

While there are some challenges associated with this approach, such as time required in field and overall costs, the benefits of reaching a broader range of respondents and improving response rates make it a valuable tool.