Construct validity

Tuesday, November 26th, 2013

Reliability of a test as a questionnaire means that the questionnaire is measuring something in a reproducible way. Validity on the other hand means that the questionnaire is measuring what is intended to. In situations where other scales of the same or similar attributes are available, outcomes of an existing scale and the new one administered to a sample of people may be compared with their correlation indicating the validity of the new scale. However, if no other measure pre-exists, another approach is necessary called ´construct validity´.(1) read more

Data saturation

Monday, November 25th, 2013

Theoretical saturation of data is a term in qualitative research, mostly used in the grounded theory approach. Theoretical saturation of data means that researchers reach a point in their analysis of data that sampling more data will not lead to more information related to their research questions.(1) No additional data can be found to develop new properties of categories and the relationships between the categories are disentangled. Researchers see in their data similar instances over and over again and that make them empirically confident that their categories are saturated, the descriptions of these categories are thick and a theory can emerge. Researchers are allowed to stop sampling data and to round off their analysis. read more

Delphi consensus procedure

Tuesday, November 26th, 2013

The aim of a Delphi consensus procedure, named after the ancient Delphic oracle, is to determine the extent to which people agree about a given issue or to develop consensus. (1;2) This anonymous process can be organized by inviting experts to discuss on the matter or relevant individuals to rate their agreement on opinions e.g. statements, on a scale e.g. from 1 (total disagreement) to 9 (total agreement), and to give comments. read more

Focus group

Tuesday, November 26th, 2013

The focus group method is a well-known method in qualitative research aiming to find meanings and significances people attach to certain phenomena. The hallmark of the focus group method is the interaction of the participants.(1-5) Market researchers developed this method but social scientists and primary health care researchers also use focus groups to explore people’s belief, opinions and attitudes.(4) In fact this method is a kind of a face to face interview but the mostly 6-8 participants are able to talk to one another, to talk and to ask questions, stimulating each other to share experiences and opinions. read more

Grounded Theory

Tuesday, November 26th, 2013

In 1967, Glaser and Strauss outlined a scheme for grounded theorizing, which is a method in qualitative research guiding researchers in finding linkages between data and theory.(1;2) Theoretical sampling and constant comparison are the main principles. read more

Linguistic validity

Tuesday, November 26th, 2013

Linguistic validity means that different language versions of an instrument such as a questionnaire are conceptually equivalent in each of the target countries. (1-3) Such questionnaires should be understood and practically performed in the same way. Linguistic and cross-cultural aspects must be taken into account as well the concept related to the questionnaire involved. Linguistic validity can be reached by means of a forward-backward translation procedure. read more

Nominal group technique

Wednesday, May 15th, 2013

The nominal group technique (NGT) is a qualitative research method of judgmental decision-making involving four phases (generating ideas, recording them, evaluation and group decision). The technique enables researchers to gather information from relevant experts facilitating creative problem solving by means of judgmental decision making in situations where routine answers are inadequate.(1-5) This means that the judgments of experts on the topic are integrated. read more


Wednesday, November 27th, 2013

Triangulation is a term in qualitative research methods derived from navigation, in which sailors try to discover their exact position on a map by taking bearings on two landmarks. The methodological triangulation is the most frequently applied approach, using different methods when studying a subject (1) such as the combination of ethnographic observations with interviews or the mixed methods approach which is mixing qualitative and quantitative methods in one study.(2) Denzin discerned three other types of triangulation next to the methodological triangulation: data, investigator and theory triangulation.(3) read more