Chapter 6
Methods of Data Collection
(Note:
For the concept map that goes with this lecture, click
here. Remember: concept maps help provide the big picture as well as show
how the parts are interrelated.)
The purpose of Chapter 6 is to help you to learn how to
collect data for a research project.
- The
term method of data collection simply refers to how the researcher
obtains the empirical data to be used to answer his or her research
questions.
- Once
data are collected they are analyzed and interpreted and turned into
information and results or findings.
- All
empirical research relies on one or more method of data collection.
It is important to consider and utilize the fundamental
principle of mixed research during the planning of a research study.
- The
principle states that researchers should mix methods (including methods of
data collection as well as methods of research) in a way that is likely to
provide complementary strengths and nonoverlapping weaknesses.
- We
will provide you with additional tables (not in the chapter because of
space limitations) for each method of data collection so that you can compare
the strengths and weaknesses of each method of data collection and attempt
to put together the match that will best serve your purpose and will
follow the fundamental principle of mixed research.
- The
focus in this chapter is on methods of data collection, not methods of
research (which are covered in later chapters).
There are six major methods of data collection. We will
briefly summarize each of these in this lecture:
- Tests
(i.e., includes standardized tests that usually include information on reliability,
validity, and norms as well as tests constructed by researchers for
specific purposes, skills tests, etc).
- Questionnaires
(i.e., self-report instruments).
- Interviews
(i.e., situations where the researcher interviews the participants).
- Focus
groups (i.e., a small group discussion with a group moderator present
to keep the discussion focused).
- Observation
(i.e., looking at what people actually do).
- Existing
or Secondary data (i.e., using data that are originally collected and
then archived or any other kind of “data” that was simply left behind at
an earlier time for some other purpose).
Tests
Tests are commonly used in
research to measure personality, aptitude, achievement, and performance. The
last chapter discussed standardized tests; therefore, we only have a brief
discussion in this chapter. Note that tests can also be used to complement
other measures (following the fundamental principle of mixed research).
In addition to the tests discussed in the last chapter, note that
sometimes, a researcher must develop a new test to measure the specific
knowledge, skills, behavior, or cognitive activity that is being studied. For
example, a researcher might need to measure response time to a memory task
using a mechanical apparatus or develop a test to measure a specific mental or
cognitive activity (which obviously cannot be directly observed).
·
An excellent source of tests (and other measures) (that
we didn’t get into the chapter in time) is called The Directory of Unpublished
Experimental Mental Measures (2003) edited by Goldman and Mitchell,
published by the American Psychological Association.
·
We list the major sources of tests and test reviews in
Table 5.7.
·
We listed the major internet sources for finding tests in
Table 5.8
·
Remember that if a test has already been developed that
purports to measure what you want to measure, then you should strongly consider
using it rather.
The following table
lists the strengths and weaknesses of tests. It, in conjunction with the tables
for the other five major methods of data collection, will help you in applying
the fundamental principle of mixed research:
Strengths and Weaknesses of Tests
Strengths
of tests (especially standardized tests)
- Can provide measures of
many characteristics of people.
- Often standardized
(i.e., the same stimulus is provided to all participants).
- Allows comparability of
common measures across research populations.
- Strong psychometric
properties (high measurement validity).
- Availability of
reference group data.
- Many tests can be
administered to groups which saves time.
- Can provide “hard,”
quantitative data.
- Tests are usually
already developed.
- A wide range of tests
is available (most content can be tapped).
- Response rate is high
for group administered tests.
- Ease of data analysis
because of quantitative nature of data.
Weaknesses
of tests (especially standardized tests)
- Can be expensive if
test must be purchased for each research participant.
- Reactive effects such
as social desirability can occur.
- Test may not be
appropriate for a local or unique population.
- Open-ended questions
and probing not available.
- Tests are sometimes
biased against certain groups of people.
- Nonresponse to selected
items on the test.
- Some tests lack
psychometric data.
Questionnaires
A questionnaire is a self-report data collection
instrument that is filled out by research participants. Questionnaires are
usually paper-and-pencil instruments, but they can also be placed on the web
for participants to go to and “fill out.” Questionnaires are sometimes called
survey instruments, which is fine, but the actual questionnaire should not be called “the survey.” The word
“survey” refers to the process of using a questionnaire or interview protocol
to collect data. For example, you might do a survey of teacher attitudes about
inclusion; the instrument of data collection should be called the questionnaire
or the survey instrument.
- A
questionnaire is composed of questions and/or statements.
- Because
one way to learn to write questionnaires is to look at other
questionnaires, here is an example of a typical questionnaire that has
mostly quantitative items, click
here.
- For
an example of a qualitative questionnaire, click
here.
- When
developing a questionnaire make sure that you follow the 15 Principles
of Questionnaire Construction.
I will briefly review the 15 principles now.
Principle 1: Make sure the
questionnaire items match your research objectives.
Principle 2: Understand your research participants.
- Your
participants (not you!) will be filling out the questionnaire.
- Consider
the demographic and cultural characteristics of your potential
participants so that you can make it understandable to them.
Principle 3: Use natural and familiar language.
- Familiar
language is comforting; jargon is not.
Principle 4: Write items that are clear, precise, and
relatively short.
- If
your participants don't understand the items, your data will be invalid
(i.e., your research study will have the garbage in, garbage out, GIGO,
syndrome).
- Short
items are more easily understood and less stressful than long items.
Principle 5: Do not use "leading" or
"loaded" questions.
- Leading
questions lead the participant to where you want him or her to be.
- Loaded
questions include loaded words (i.e., words that create an emotional reaction
or response by your participants).
- Always
remember that you do not want the participant's response to be the result
of how you worded the question. Always use neutral wording.
Principle 6: Avoid double-barreled questions.
- A
double-barreled question combines two or more issues in a single question
(e.g., here is a double barreled question: “Do you elicit information from
parents and other teachers?” It’s double barreled because if someone
answered it, you would not know whether they were referring to parents or
teachers or both).
- Does
the question include the word "and"? If yes, it might be a
double-barreled question.
- Answers
to double-barreled questions are ambiguous because two or more ideas are
confounded.
Principle 7: Avoid double negatives.
- Does
the answer provided by the participant require combining two negatives?
(e.g., "I disagree that teachers should not be required to
supervise their students during library time"). If yes, rewrite it.
Principle 8: Determine whether an open-ended or a closed
ended question is needed.
- Open-ended
questions provide qualitative data in the participants' own words.
Here is an open ended question: How can your principal improve the morale
at your school? _______________________________________________
- Closed-ended
questions provide quantitative data based on the researcher's response
categories. Here is an example of a closed-ended question:

- Open-ended
questions are common in exploratory research and closed-ended questions
are common in confirmatory research.
Principle 9: Use mutually exclusive and exhaustive response
categories for closed-ended questions.
- Mutually
exclusive categories do not overlap (e.g., ages 0-10, 10-20, 20-30 are
NOT mutually exclusive and should be rewritten as less than 10, 10-19,
20-29, 30-39, ...).
- Exhaustive
categories include all possible responses (e.g., if you are doing a
national survey of adult citizens (i.e., 18 or older) then the these
categories (18-19, 20-29, 30-39, 40-49, 50-59, 60-69) are NOT exhaustive
because there is no where to put someone who is 70 years old or
older.
Principle 10: Consider the different types of response
categories available for closed-ended questionnaire items.
- Rating
scales are the most commonly used, including:
- Numerical rating scales (where the endpoints are anchored;
sometimes the center point or area is also labeled).
1 2 3 4 5 6 7
Very Low Very High
- Fully anchored rating scales (where all the points on the scale are
anchored).
1 2 3 4 5
Strongly Agree
Neutral Disagree Strongly
Agree
Disagree
1 2 3 4
Strongly Agree
Disagree Strongly
Agree
Disagree
- Omitting the center point on a rating
scale (e.g., using a 4-point rather than a 5-point rating scale) does not
appreciably affect the response pattern. Some researchers prefer 5- point
rating scales; other researchers prefer 4-point rating scales. Both
generally work well.
- You should use somewhere from four to
eleven points on your rating scale. Personally, I like the 4 and 5-point
scales because all of the points are easily anchored.
- I
do not recommend a 1 to 10 scale because too many respondents mistakenly
view the 5 as the center point. If you want to use a wide scale like this,
use a 0 to 10 scale (where the 5 is the middle point) and label the 5
with the anchor “medium” or some other appropriate anchor.
- Rankings
(i.e., where participants put their responses into rank order, such as
most important, second most important, and third most important).
- Semantic
differential (i.e., where one item stem and multiple scales, that are
anchored with polar opposites or antonyms, are included and are rated by
the participants).
- Checklists
(i.e., where participants "check all of the responses in a list that
apply to them").
Principle 11: Use multiple items to measure abstract
constructs.
- This
is required if you want your measures to have high reliability and
validity.
- One
approach is to use a summated rating scale(such as the Rosenberg
Self-Esteem Scale that is composed of 10 items, with each item measuring
self-esteem).
- Another
name for a summated rating scale is a Likert Scale because the
summated rating scale was pretty much invented by the famous social psychologist
named Rensis Likert.
- Here
is the Rosenberg Self-Esteem Scale, which is a summated rating scale:

Principle 12: Consider using multiple methods when measuring
abstract constructs.
- The
idea here is that if you only use one method of measurement, then your
measurement may be an artifact of that method of measurement.
- On
the other hand, if you use two or more methods of measurement you will be
able to see whether the answers depend on the method (i.e., are the
answers corroborated across the methods of measurement or do you get
different answers for the different methods?). For example, you might
measure student’s self-esteem via the Rosenberg Scale just shown (which is
used in a self-report form) as well as using teachers’ ratings of the
students’ self-esteem; you might even want to observe the students in
situations that should provide indications of high and low
self-esteem.
Principle 13: Use caution if you reverse the wording in some
of the items to prevent response sets. (A response set is the
tendency of a participant to respond in a specific direction to items
regardless of the item content.)
- Reversing
the wording of some items can help ensure that participants don't just
"speed through" the instrument, checking "yes" or
"strongly agree" for all the items.
- On
the other hand, you may want to avoid reverse wording if it creates a
double negative.
- Also,
recent research suggests that the use of reverse wording reduces the
reliability and validity of scales. Therefore, you should generally use reverse
wording sparingly, if at all.
Principle 14: Develop a questionnaire that is easy for
the participant to use.
- The
participant must not get confused or lost anywhere in the questionnaire.
- Make
sure that the directions are clear and that any filter questions
used are easy to follow.
Principle 15: Always pilot test your questionnaire.
- You
will always find some problems that you have overlooked!
- The
best pilot tests are with people similar to the ones to be included in
your research study.
- After
pilot testing your questionnaire, revise it and pilot test it again, until
it works correctly.
The following table lists the strengths and weaknesses of questionnaires.
It, in conjunction with the tables for the other five major methods of data collection,
will help you in applying the fundamental principle of mixed research:
Strengths and Weaknesses of Questionnaires
Strengths of questionnaires
- Good for measuring
attitudes and eliciting other content from research participants.
- Inexpensive (especially
mail questionnaires and group administered questionnaires).
- Can provide information
about participants’ internal meanings and ways of thinking.
- Can administer to
probability samples.
- Quick turnaround.
- Can be administered to
groups.
- Perceived anonymity by
respondent may be high.
- Moderately high
measurement validity (i.e., high reliability and validity) for well
constructed and validated questionnaires.
- Closed-ended items can
provide exact information needed by researcher.
- Open-ended items can
provide detailed information in respondents’ own words.
- Ease of data analysis
for closed-ended items.
- Useful for exploration
as well as confirmation.
Weaknesses of questionnaires
- Usually must be kept
short.
- Reactive effects may
occur (e.g., interviewees may try to show only what is socially
desirable).
- Nonresponse to
selective items.
- People filling out
questionnaires may not recall important information and may lack
self-awareness.
- Response rate may be
low for mail and email questionnaires.
- Open-ended items may reflect
differences in verbal ability, obscuring the issues of interest.
- Data analysis can be
time consuming for open-ended items.
- Measures need
validation.
Interviews
In an interview, the interviewer asks the interviewee
questions (in-person or over the telephone).
- Trust
and rapport are important.
- Probing
is available (unlike in paper-and-pencil questionnaires) and is used to
reach clarity or gain additional information
- Here are some examples of standard
probes:
- Anything else?
- Any other reason?
- What do you mean?
Interviews may be quantitative or qualitative.
Quantitative interviews:
- Are standardized (i.e., the same
information is provided to everyone).
- Use closed-ended questions.
- Exhibit 6.3 has an example of an
interview protocol. Note that it looks very much like a
questionnaire! The key difference between an interview protocol and a
questionnaire is that the interview protocol is read by the interviewer
who also records the answers (you have probably participated in telephone
surveys before...you were interviewed).
Qualitative interviews
- They are based on open-ended questions.
- There
are three types of qualitative interviews.
1) Informal Conversational Interview.
- It is spontaneous.
- It is loosely structured (i.e., no interview protocol us used).
2) Interview Guide Approach.
- It
is more structured than the informal conversational interview.
- It
includes an interview protocol listing the open-ended questions.
- The questions
can be asked in any order by the interviewer.
- Question
wording can be changed by the interviewer if it is deemed appropriate.
3) Standardized Open-Ended
Interview.
- Open-ended
questions are written on an interview protocol, and they are asked in the
exact order given on the protocol.
- The
wording of the questions cannot be changed.
The following table
lists the strengths and weaknesses of interviews. It, in conjunction with the
tables for the other five major methods of data collection, will help you in
applying the fundamental principle of mixed research:
Strengths and Weaknesses of Interviews
Strengths
of interviews
- Good for measuring
attitudes and most other content of interest.
- Allows probing and
posing of follow-up questions by the interviewer.
- Can provide in-depth
information.
- Can provide information
about participants’ internal meanings and ways of thinking.
- Closed-ended interviews
provide exact information needed by researcher.
- Telephone and e-mail
interviews provide very quick turnaround.
- Moderately high
measurement validity (i.e., high reliability and validity) for well
constructed and tested interview protocols.
- Can use with
probability samples.
- Relatively high
response rates are often attainable.
- Useful for exploration
as well as confirmation.
Weaknesses
of interviews
- In-person interviews
usually are expensive and time consuming.
- Reactive effects (e.g.,
interviewees may try to show only what is socially desirable).
- Investigator effects may
occur (e.g., untrained interviewers may distort data because of personal
biases and poor interviewing skills).
- Interviewees may not
recall important information and may lack self-awareness.
- Perceived anonymity by
respondents may be low.
- Data analysis can be
time consuming for open-ended items.
- Measures need
validation.
Focus Groups
A focus group is a situation where a focus group
moderator keeps a small and homogeneous group (of 6-12 people) focused on
the discussion of a research topic or issue.
- Focus
group sessions generally last between one and three hours and they are
recorded using audio and/or videotapes.
- Focus
groups are useful for exploring ideas and obtaining in-depth information
about how people think about an issue.
The following table
lists the strengths and weaknesses of focus groups. It, in conjunction with the
tables for the other five major methods of data collection, will help you in
applying the fundamental principle of mixed research:
Strengths and Weaknesses of Focus Groups
Strengths
of focus groups
- Useful for exploring
ideas and concepts.
- Provides window into
participants’ internal thinking.
- Can obtain in-depth
information.
- Can examine how
participants react to each other.
- Allows probing.
- Most content can be
tapped.
- Allows quick
turnaround.
Weaknesses
of focus groups
- Sometimes expensive.
- May be difficult to
find a focus group moderator with good facilitative and rapport building
skills.
- Reactive and
investigator effects may occur if participants feel they are being watched
or studied.
- May be dominated by one
or two participants.
- Difficult to generalize
results if small, unrepresentative samples of participants are used.
- May include large
amount of extra or unnecessary information.
- Measurement validity
may be low.
- Usually should not be
the only data collection methods used in a study.
- Data analysis can be
time consuming because of the open-ended nature of the data.
Observation
In the method of data collection called observation,
the researcher observes participants in natural and/or structured environments.
- It
is important to collect observational data (in addition to attitudinal
data) because what people say is not always what they do!
Observation can be carried out in two types of environments:
- Laboratory
observation (which is done in a lab set up by the researcher).
- Naturalistic
observation (which is done in real-world settings).
There are two important forms of observation:
quantitative observation and qualitative observation.
1) Quantitative observation involves standardization
procedures, and it produces quantitative data.
- The
following can be standardized:
- Who is observed.
- What is observed.
- When the observations are to take place.
- Where the observations are to take place.
- How the observations are to take place.
- Standardized
instruments (e.g., checklists) are often used in quantitative observation.
- Sampling
procedures are also often used in quantitative observation:
--Time-interval sampling (i.e., observing during time intervals,
e.g., during the
first minute of each 10
minute interval).
--Event sampling (i.e., observing after an event has taken
place, e.g., observing
after teacher asks a
question).
2) Qualitative observation is exploratory and open-
ended, and the researcher takes extensive field notes.
The qualitative
observer may take on four different roles that make up a continuum:
·
Complete
participant (i.e., becoming a full member of the group and not informing the
participants that you are studying them).
·
Participant-as-Observer
(i.e., spending extensive time "inside" and informing the
participants that you are studying them).
·
Observer-as-Participant
(i.e., spending a limited amount of time "inside" and informing them
that you are studying them).
·
Complete
Observer (i.e., observing from the "outside" and not informing that
participants that you are studying them).
The following table
lists the strengths and weaknesses of observational data. It, in conjunction
with the tables for the other five major methods of data collection, will help
you in applying the fundamental principle of mixed research:
Strengths and Weaknesses of Observational Data
Strengths
of observational data
- Allows one to directly
see what people do without having to rely on what they say they do.
- Provides firsthand
experience, especially if the observer participates in activities.
- Can provide relatively
objective measurement of behavior (especially for standardized
observations).
- Observer can determine
what does not occur.
- Observer may see things
that escape the awareness of people in the setting.
- Excellent way to
discover what is occurring in a setting.
- Helps in understanding
importance of contextual factors.
- Can be used with
participants with weak verbal skills.
- May provide information
on things people would otherwise be unwilling to talk about.
- Observer may move
beyond selective perceptions of people in the setting.
- Good for description.
- Provides moderate
degree of realism (when done outside of the laboratory).
Weaknesses
of observational data
- Reasons for observed
behavior may be unclear.
- Reactive effects may
occur when respondents know they are being
observed (e.g., people being observed may behave in
atypical ways).
- Investigator effects
(e.g., personal biases and selective perception of observers)
- Observer may “go
native” (i.e., over-identifying with the group being studied).
- Sampling of observed
people and settings may be limited.
- Cannot observe large or
dispersed populations.
- Some settings and
content of interest cannot be observed.
- Collection of
unimportant material may be moderately high.
- More expensive to
conduct than questionnaires and tests.
- Data analysis can be
time consuming.
Secondary/Existing
Data
Secondary data (i.e., data originally used for a different
purpose) are contrasted with primary data (i.e., original data collected
for the new research study).
The most
commonly used secondary data are documents, physical data, and archived
research data.
1. Documents. There are two main kinds of
documents.
·
Personal
documents (i.e., things
written or recorded for private purposes). Letters, diaries, family pictures.
·
Official documents (i.e., things written or
recorded for public or private organizations). Newspapers, annual reports, yearbooks, minutes.
2. Physical data (are any material thing
created or left by humans that might provide information about a phenomenon of
interest to a researcher).
3. Archived research data (i.e., research data collected
by other researchers for other purposes, and these data are save often in tape
form or cd form so that others might later use the data). For the biggest
repository of archived research data, click
here.
The following table
lists the strengths and weaknesses of secondary/existing data. It, in
conjunction with the tables for the other five major methods of data
collection, will help you in applying the fundamental principle of mixed
research:
Strengths and Weaknesses of Secondary Data
Strengths
of documents and physical data:
- Can provide insight
into what people think and what they do.
- Unobtrusive, making
reactive and investigator effects very unlikely.
- Can be collected for
time periods occurring in the past (e.g., historical data).
- Provides useful
background and historical data on people, groups, and organizations.
- Useful for
corroboration.
- Grounded in local
setting.
- Useful for exploration.
Strengths
of archived research data:
- Archived research data
are available on a wide variety of topics.
- Inexpensive.
- Often are reliable and
valid (high measurement validity).
- Can study trends.
- Ease of data analysis.
- Often based on high
quality or large probability samples.
Weaknesses
of documents and physical data:
- May be incomplete.
- May be representative
only of one perspective.
- Access to some types of
content is limited.
- May not provide insight
into participants’ personal thinking for physical data.
- May not apply to
general populations.
Weaknesses
of archived research data:
- May not be available
for the population of interest to you.
- May not be available
for the research questions of interest to you.
- Data may be dated.
- Open-ended or
qualitative data usually not available.
- Many of the most
important findings have already been mined from the data.