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Qualitative Research: Methods

Table of Contents: Methods Section

Duke Resources

Duke's Office of Assessment:

Assessment Resources (qualitative and quantitative)

FHI 360

Qualitative Research Methods: A Data Collector's Field Guide
Downloadable how-to guide covers the mechanics of data collection for applied qualitative research; appropriate for novice and experienced researchers.



In qualitative research, only a sample (subset) of a population is selected for any given study.Three of the most common sampling methods are:

  • Purposive sampling
    Participants are grouped according to preselected criteria relevant to a particular research question; sample sizes often determined by theoretical saturation (new data doesn't bring additional insights)
  • Quota sampling
    While designing a study, it is determined how many people with which characteristics need to be included as participants
  • Snowball sampling
    Participants or informants use their social networks to refer the researcher to other people who could potentially participate in the study, often used to find and recruit “hidden populations"

Choosing a Method for Collecting Qualitative Data


Overall Purpose



  •  Quickly and/or easily gets lots of  information from people in a non threatening way
  • can complete anonymously
  • inexpensive to administer
  • easy to compare and analyze
  • administer to many people
  • can get lots of data
  • many sample questionnaires already exist
  • might not get careful feedback
  • wording can bias client's responses
  • impersonal
  • may need sampling expert
  • doesn't get full story
  • Understand someone's impressions or experiences
  • Learn more about answers to questionnaires
  • get full range and depth of information
  • develops relationship with client
  • can be flexible with client
  • can take ime
  • can be hard to analyze and compare
  • can be costly
  • interviewer can bias client's responses
  • Gather firsthand information about people, events, or programs
  • view operations of a program as they are actually occurring
  • can adapt to events as they occur
  • can be difficult to interpret seen behaviors
  • can be complex to categorize observations
  • can influence behaviors of program participants
  • can be expensive
 Focus groups
  • Explore a topic in depth through group discussion
  • quickly and reliably get common impressions
  • can be efficient way to get much range and depth of information in short time
  • can convey key information about programs
  • can be hard to analyze responses
  • need good facilitator for safety and closure
  • difficult to schedule 6-8 people together
 Case studies
  • Understand an experience or conduct comprehensive examination through cross comparison of cases
  • depicts client's experience in program input, process and results
  • powerful means to portray program to outsiders
  • usually time consuming to collect, organize and describe
  • represents depth of information, rather than breadth

Table was adapted from the Basic Guide to Program Evaluation,