Qualitative research is used to help us understand how people feel and why they feel as they do. It is concerned with collecting in-depth information. Samples tend to be smaller compared with quantitaive projects that include much larger samples. Depth interviews or group discussions are two common methods used for collecting qualitative information.
This research method usually emphasises quantification in the collection and analysis of data. It is used to answer questions with quantifiable answers such as 'How many...', 'How much...', 'How often...'. The results of quantitative research can usually be summarised numerically using frequencies, percentages and averages. Quantitative research methods include surveys, questionnaires and clinical trials.
A data collection instrument which tends to consist of a number of questions requiring closed-ended and open-ended responses. It can be completed directly by respondents (self-completion) or administered to respondents by an interviewer. It can be administered using a variety of means such paper and pen or computer and through a number of channels such as by post, by telephone or online.
A non-probability sampling method that requires the sample to include specific proportions of different categories of respondents. For example, if you wanted to ensure that an equal number of men and women were included in research you could place quotas the sample based on gender so that 50% were men and 50% were women. Quotas are often used to reflect the proportion of people falling into each category in the population of interest.