Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Chapter 15 Sampling and Data Collection in Qualitative Studies

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Sampling in Qualitative Research Selection of sample members guided by desire for information-rich sources “Representativeness” not a key issue Random selection not considered productive

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Types of Qualitative Sampling Convenience (volunteer) sampling Snowball sampling Purposive sampling Theoretical sampling

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Types of Purposive Sampling in Qualitative Research Maximum variation sampling Extreme/deviant case sampling Typical case sampling Criterion sampling Confirming and disconfirming cases

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Theoretical Sampling Preferred sampling method in grounded theory research Involves selecting sample members who best facilitate and contribute to the development of the emerging theory

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Is the following statement True or False? Sampling in qualitative research is guided more by the desire for rich sources of information than by the need for random selection.

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer True Rationale: Selection of sample members for qualitative research is guided by the desire for information-rich sources. The representativeness of the sample is not a key aspect and random selection is not considered productive.

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Sample Size in Qualitative Research No explicit, formal criteria Sample size determined by informational needs Decisions to stop sampling guided by data saturation Data quality can affect sample size.

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Sampling in the Main Qualitative Traditions Ethnography −Mingling with many members of the culture—a “big net” approach −Informal conversations with 25 to 50 informants −Multiple interviews with smaller number of key informants

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Sampling in Phenomenology Relies on very small samples (often 10 or fewer) Participants must have experienced phenomenon of interest.

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Sampling in Grounded Theory Typically involves samples of 20 to 40 people Selection of participants who can best contribute to emerging theory (usually theoretical sampling)

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Data Collection in Qualitative Studies Data collection methods may change as study progresses. In-depth interviews most common method Observation also common

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Types of Qualitative Self-Report Techniques Unstructured interviews –Conversational, totally flexible –Use of grand tour questions Semistructured interviews –Use of a topic guide

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Types of Qualitative Self-Report Techniques (cont.) Focus group interviews –Interviews in small groups (5 to 10 people) –Led by a moderator Diaries –Source in historical research –Provide intimate detail of everyday life

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Types of Qualitative Self-Report Techniques (cont.) Critical incidents interviews –Focuses on specific incidents that had a discernible impact on some outcome Photo elicitation –Interview stimulated and guided by photographic images

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Is the following statement True or False? A focus group typically involves at least 10 to 15 people.

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer False Rationale: A focus group usually involves interviews with small groups, ranging in size from 5 to 10 people.

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Qualitative Observational Methods Qualitative studies: unstructured observation in naturalistic settings –Includes participant observation

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins The Observer–Participant Role in Participant Observation Leininger’s four-phase sequence: –Primarily observation –Primarily observation with some participation –Primarily participation with some observation –Reflective observation

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Question Is the following statement True or False? In qualitative studies, observation is unstructured.

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer True Rationale: Observation with a qualitative study is unstructured and occurs in naturalistic settings.

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Recording Observations Logs (field diaries) Field notes –Descriptive (observational) notes –Reflective notes: Methodologic notes Theoretical notes (or analytical notes) Personal notes

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Observational Rating Scales Ratings are on a descriptive continuum, typically bipolar. Ratings can occur: –At specific intervals –Upon the occurrence of certain events –After an observational session (global ratings)

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Evaluation of Unstructured Observational Methods Excellent method for capturing many clinical phenomena and behaviors Potential problem of reactivity when people are aware that they are being observed Risk of observational biases—factors that can interfere with objective observation

Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins End of Presentation