How to collect quantitative data?

The vast majority of quantitative data collection techniques used for research studies involve numerical collection. The use of numbers to assess large-scale data allows market researchers, such as you, to evaluate the results using statistical analysis and look for greater meaning in the data. The most common forms of quantitative data collection include:

  1. Probability sampling
  2. Questionnaires
  3. Rating scales
  4. Census

Typically, quantitative data is collected and recorded systematically, so that it can be analysed within a computer database, as well as tables and graphs to uncover large-scale trends and patterns that support theories and arguments.

Ultimately, quantitative data can be used to either challenge a viewpoint derived from theory or more accurately estimate the potential scope of a particular area of interest. The following four data collection methods can be used to summarise, compare, contrast and generalise.


Probability sampling

A form of random selection, probability sampling enables market researchers to make probability statements using sample data gathered at random from a target demographic.

The essence of probability sampling is that it enables you to obtain sample data that’s representative of the people you are interested in studying. As the data is collated purely at random, this type of quantitative data collection rules out the possibility of sampling bias.

There are three types of probability sampling:

  1. Simple random sampling – with this method, there is an equal probability that any of your target demographic could be chosen for inclusion in your sample.

  2. Systematic random sampling – a slight variation on simple random sampling; although there’s still an equal chance that any of your target demographic could be included in your sample, instead of using random number tables to select the first unit for inclusion in your sample, the remaining units are chosen in an ordered fashion e.g. one in every 10 people on a list.

  3. Stratified random sampling – sometimes we’re specifically interested in a particular group within your target demographic i.e. males or females, managers or executives. This type of sampling gives you an equal chance of selecting each unit from a particular group of your target demographic when creating a sample.


Questionnaires are designed to quantify and legitimise people’s beliefs and behaviours. Generally, two types of questionnaires are used to collect quantitative data for market research purposes: mail and web-based questionnaires.

The advantage of mail questionnaires is that they can be sent to high volumes of people very quickly, without the need to spend time and money on interviewing each respondent on an individual basis. Very often respondents tend to be more honest about their beliefs due to the fact that all responses are anonymous, allowing them to reply without fear of prejudice.

Web-based questionnaires can be equally cost-effective, with the ability to send the surveys quicker and with an optimal amount of detail for the respondent.

The issue with both direct mail and web-based questionnaires is that it’s harder to encourage everyone to respond. In fact, you’ll very often find that more people won’t return the questionnaire than those that do!

Additionally, the validity of such questionnaires can sometimes be called into question as there’s no certainty as to the accuracy of responses.

Rating scales

Rating scales are particularly useful in scenarios where you wish to ask respondents their satisfaction with an item or service. It’s a good way of quickly determining a general bias and help you ascertain where to invest your effort in improving your offering.

Nevertheless, survey data is only as good as the questions you ask, so it’s important that rating scales are designed to be easy to understand for respondents. Every scale point should be easy for respondents to interpret and there should be enough scale points to differentiate respondents as validly as possible.

Generally, a five-point rating scale tends to work well: very poor, poor, UK, good and very good.


Arguably the most comprehensive and systematic way of acquiring and recording information about your target demographic, a census is quantitative data collection on the biggest scale imaginable. Although it is most popular for national population and housing censuses, other common censuses carried out include those for agricultural, business and traffic purposes.

Since the early 20th century, censuses have been recording household data, along with a host of employment indicators, for governments to digest and plot growing trends on the biggest scale possible.

Now, smaller scale censuses are created in a whole host of formats, made to be accessible to anyone from teachers and charities through to the media and local governance.


Keep in mind that the Business & IP Centre can help you increase your knowledge of specific market sectors. We have wide-ranging data sources ready for you to use on-site to better understand everything from key legislation affecting your industry and emerging technologies through to potential opportunities created by economic, cultural or social changes. Our ‘Introduction to using the Business & IP Centre’ workshop equips you with all the tools you need to carry out free market research and browse national and international property databases.

Plan to start your business

Protecting your ideas