Qualitative research differs from quantitative research in several important ways, though the two types of research are perfectly compatible and many of the best studies combine or 'triangulate' both approaches. For instance, the starting point of qualitative research is fundamentally different from that of quantitative research. Rather than beginning with a hypothesis, qualitative research designs will begin with a blank slate, open to whatever is found and with no preconceptions about the causes of a phenomenon. The methods of qualitative research are exploratory "“ theories and propositions are developed, altered and amended as the research progresses in light of new data as it emerges. This is often referred to as grounded theory. A related term is analytic induction, which refers to the process whereby the proposition is constantly modified as new as new findings emerge. The researcher can search for evidence which falsifies the theory that is developing, until no further contradictory evidence can be found. Qualitative research allows scope for exploring a variety of perspectives rather than seeking one universal truth.

For example, an unmet need has been identified by staff working with young offenders on a probation programme. The staff have found that increasing numbers of young people leaving prison are encountering problems in securing and maintaining accommodation. They would like to find out why this is so. Staff were aware of the legalistic and structural barriers that hinder young people in finding and sustaining accommodation, but also wanted to explore the perspectives of the young people themselves in order to find out if a service could be set up that would meet their needs. Rather than impose their own solution on the situation, they felt it would be better to put themselves in the shoes of the young people.

A qualitative study could help the researcher understand the needs of this client group.   A focus group of young people who have left prison could help identify their feelings and attitudes towards accommodation, including what sort of help and support they feel they could benefit from.   Unstructured interviews could also be used to reveal this sort of information.   Participant observation could be another qualitative method employed, in which the researcher immerses themselves in the social world of the young people leaving prison in order to experience the challenges they face.

Qualitative research for evidence-based practice .

There is often a misconception that qualitative research designs are devalued by evidence-based approaches. This is only true to the extent that any study design which is not used for the task to which it is best suited, and/or not carried out properly, may be criticised. However, good, robust, qualitative research has a firm place within the evidence-based approach. Quite simply, there are certain questions that quantitative designs are better at exploring, and some that are better addressed by qualitative designs. While quantitative research is useful for 'what works' type questions, it is not very good at discovering why things work using these methods and what people actually think and feel about approaches or interventions. Herein lie the strengths of qualitative research: its methods allow us to uncover the meaning that is attached to things by people.

There have been recent arguments for an increased focus on qualitative issues in the design of performance indicators and in evidence-based approaches.   Although evidence-based practice is more commonly associated with 'outcomes' research, testing the efficacy of interventions, there is growing awareness of the importance of the perspectives of service users and carers in the social care field, and qualitative designs are well-suited to uncovering this sort of data.   Qualitative investigations are also increasingly used in preparatory work for trials, especially in deciding which clinical questions are most important to patients of service users.

Qualitative methods include interviews (unstructured or semi-structured); focus groups; participant observation (covert or overt); survey with open-ended questions; content analysis (e.g. identifying themes which arise in secondary sources such as newspaper articles or case files).   Client opinion studies can be qualitative or quantitative, depending on the sorts of questions asked.   Those with 'open-ended' rather than 'fixed response' questions would fall into the category of 'qualitative'.