Data Collection Methods

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Data Collection Methods
Data Collection Plan
Basic decision is use of:
• New data, collected specifically for research
purposes, or
• Existing data
– Records (e.g., patient charts)
– Historical data
– Existing data set (secondary analysis)
Examples of Records, Documents, and
Available Data
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Hospital records (e.g., nurses’ shift reports)
School records (e.g., student absenteeism)
Corporate records (e.g., health insurance choices)
Letters, diaries, minutes of meetings, etc.
Photographs
Major Types of Data Collection
Methods
• Self-reports
• Observation
• Biophysiologic measures
Dimensions of Data Collection
Approaches
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Structure
Quantifiability
Researcher obtrusiveness
Objectivity
Types of Qualitative Self-Reports
• Unstructured interviews
– Conversational, totally flexible
– Use of grand tour questions
• Semistructured interviews
– Use of a topic guide
Types of Qualitative Self-Reports (cont.)
• Focus group interviews
– Interviews in small groups (5 to 10 people)
– Led by a moderator
• Life histories
– Narrative self-descriptions of life experiences
– Often a chronology
Types of Qualitative Self-Reports (cont.)
• Critical incidents interviews
– Focuses on specific incidents that had a
discernible impact on some outcome
• Think-aloud method
– Means of collecting data about cognitive
processes as they unfold (e.g., clinical decisionmaking)
• Diaries and journals
Question
Is the following statement True or False?
• A focus group typically involves at least 10 to 15
people.
• False
Answer
– A focus group usually involves interviews with
small groups, ranging in size from 5 to 10 people.
Structured Self-Reports
• Data are collected with a formal instrument.
– Interview schedule
• Questions are prespecified but asked orally.
• Either face-to-face or by telephone
– Questionnaire
• Questions prespecified in written form, to be selfadministered by respondents
Types of Questions in a Structured
Instrument
• Closed-ended (fixed alternative) questions
– e.g., “Within the past 6 months, were you ever a
member of a fitness center or gym?” (yes/no)
• Open-ended questions
– e.g., “Why did you decide to join a fitness center
or gym?”
Specific Types of Closed-Ended
Questions
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Dichotomous questions
Multiple-choice questions
Cafeteria questions
Rank-order questions
Forced-choice questions
Rating questions
Advantages of Questionnaires
(Compared with Interviews)
• Lower costs
• Possibility of anonymity, greater privacy
• Lack of interviewer bias
Advantages of Interviews (Compared
with Questionnaires)
• Higher response rates
• Appropriate for more diverse audiences
• Opportunities to clarify questions or to determine
comprehension
• Opportunity to collect supplementary data through
observation
Question
Which of the following would be an advantage of using
a questionnaire?
a. Higher response rates
b. Diversity of audience is not a problem.
c. Less potential for interviewer bias
d. Questions can be clarified if needed.
Answer
c. Less potential for interviewer bias
• When a questionnaire is used, there is lack of
interviewer bias along with greater privacy and
possible anonymity. Higher response rates are
obtained with interviews. Interviews also are
appropriate for more diverse audiences and provide
opportunities to clarify questions or determine
comprehension.
Composite Psychosocial Scales
• Scales—used to make fine quantitative
discriminations among people with different
attitudes, perceptions, traits
• Likert scales—summated rating scales
• Semantic differential scales
Likert Scales
• Consist of several declarative statements (items)
expressing viewpoints
• Responses are on an agree/disagree continuum (usually 5
or 7 response options).
• Responses to items are summed to compute a total scale
score.
Semantic Differential Scales
• Require ratings of various concepts
• Rating scales involve bipolar adjective pairs, with 7point ratings.
• Ratings for each dimension are summed to
compute a total score for each concept.
Example of a Semantic Differential
Visual Analog Scale (VAS)
• Used to measure subjective experiences (e.g., pain,
nausea)
• Measurements are on a straight line measuring 100
mm
• End points labeled as extreme limits of sensation
Response Set Biases
• Biases reflecting the tendency of some people to
respond to items in characteristic ways, independently
of item content
• Examples:
– Social desirability response set bias
– Extreme response set
– Acquiescence response set (yea- sayers)
– Nay-sayers response set
Question
Is the following statement True or False?
• A Likert scale would be appropriate for measuring a
person’s pain.
• False
Answer
– A visual analog scale would be more appropriate
to use when measuring a person’s pain.
Q Sorts
• Participants sort a deck of cards into piles according
to specific criteria.
• Cards contain statements to be sorted on a bipolar
continuum (e.g., most like me/least like me).
• Usually 50 to 100 cards; usually 9 or 11 piles
Vignettes
• Brief descriptions of situations to which respondents
are asked to react
• Descriptions are usually written “stories.”
• Respondents can be asked open-ended or closedended questions about their reactions.
• Aspects of the vignettes can be experimentally
manipulated.
Evaluation of Self-Reports
• Strong on directness
• Allows access to information otherwise not available
to researchers
• But can we be sure participants actually feel or act
the way they say they do?
Phenomena Amenable to Research
Observation
• Activities and behavior
• Characteristics and conditions of individuals
• Skill attainment and performance
• Verbal and nonverbal communication
• Environmental characteristics
Observation in Qualitative and
Quantitative Studies
• Qualitative studies: Unstructured observation in
naturalistic settings
– Includes Participant observation
• Quantitative studies: Structured observation of
prespecified behaviors
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
Question
Is the following statement True or False?
• In qualitative studies, observation is unstructured.
• True
Answer
– Observation with a qualitative study is
unstructured and occurs in naturalistic settings.
Recording Unstructured Observations
• Logs (field diaries)
• Field notes
– Descriptive (observational) notes
– Reflective notes:
• Methodologic notes
• Theoretical notes (or analytical notes)
• Personal notes
Structured Observations
• Category systems  Checklists
– Formal systems for systematically recording the
incidence or frequency of prespecified behaviors or
events
– Systems vary in their exhaustiveness
• Exhaustive system: All behaviors of a specific type
recorded, and each behavior is assigned to one
mutually exclusive category
• Nonexhaustive system: Specific behaviors, but not all
behaviors, recorded
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)
Observational Sampling
• Time-sampling—sampling of time intervals for observation
Examples:
• Random sampling of intervals of a given length
• Systematic sampling of intervals of a given length
• Event sampling—observation of integral events
Evaluation of 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
Biophysiologic Measures
• In vivo measurements
– Performed directly within or on living organisms
(e.g., blood pressure measures)
• In vitro measurements
– Performed outside the organism’s body (e.g.,
urinalysis)
Question
Which of the following would be classified as an in vivo
biophysiologic measure?
a. Tissue biopsy
b. Blood glucose level
c. Bacterial culture
d. Body temperature
d. Body temperature Answer
– In vivo measures are those performed directly
within or on living organisms, such as blood
pressure, body temperature, and vital capacity
measurement. Tissue biopsy, blood glucose level,
and bacterial culture are examples of in vitro
measures.
Evaluation of Biophysiologic Measures
• Strong on accuracy, objectivity, validity, and precision
• May be cost-effective for nurse researchers
• But caution may be required for their use, and
advanced skills may be needed for interpretation.
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