The Difference in Quantitative & Qualitative Data Collection

Quantitative data is information that relates to numbers, and can be measured, while qualitative data deals with information descriptions and cannot be measured or observed. These two methods of collecting data are very different from each other. Collecting qualitative data can include color, texture, smell, and taste, but collecting quantitative data involves length, speed, time, volume, and temperature.

The collection of quantitative data consists of directing experiments including clinical trials, recording observations, conducting face to face and/or telephone interviews, and issuing web-based and/or pencil questionnaires. In a clinical trial, for instance, some of the data collected can include specific information: 200 participants, 80 issued placebo, 120 issued medication, trial period of 6 months. If the trial is conducted in groups, then group numbers can be specified along with the temperatures in the rooms.

In-depth interviews, observation methods, and document reviews are three strategies used to collect qualitative data. Qualitative data may be used to improve information collected via quantitative methods. For instance, in the clinical trial example above, numerical statistics were collected. Qualitative data in the same clinical trial can include observing participants and interviewing participants before and after the trial to gather information on their perceptions. Other qualitative data can include the communicated comfort levels of participants in the room.

Qualitative and quantitative data are everywhere, but using them in research requires a manageable atmosphere to make the information more viable. In the subway, qualitative data includes descriptions like long train, orange seats, children and adults, dirty floors, people getting on and off the trains. On the other hand, quantitative data includes information such as 15 train cars, each 12 feet high, 5 children and 20 adults, 5 people get off and 2 people get on the train.

Both qualitative and quantitative data are important, especially when used in research. Ultimately, when considering the differences between qualitative and quantitative data, think about quantity (numbers and measures) and quality (descriptions). Both sets of data offer important information that, when used together, can give good overall information about various topics. As seen in the sections above, both quantitative and qualitative data can be used to support data collection in the same environment.