You have reviewed the literature, developed a hypothesis,
operationalized your variables, and given sound reasons for testing your
hypothesis. However, your preliminary work is still not done. You must now
decide exactly what specific actions you will take. In other words, although
you probably have decided on the general design (such as a simple experiment or
a 2 X 2), your plan is not complete until each detail has been thought through
and written down.
You should
write down exactly
what procedures you will follow. For example, what instructions, word for word,
will participants be given? Who will administer the treatment? Where? Will
participants be run in groups or individually? In answering these questions,
you must take into account issues of validity. However, your paramount concern
must always be ethics. You do not have the right to harm another.
Ethics should be the foundation of your research plan. Therefore, you
should read Appendix A (Ethics) before conducting a study.
In addition
to reading Appendix A, you must be extremely careful not to harm your participants. Ideally,
your participants should feel just as well when they leave the study as they
did when they began the study. Unfortunately, even in the most innocuous
studies, protecting your participants from discomfort is much easier said than
done.
Realize that any experience may be traumatic to some participants.
Trauma can occur from things you would never think of as being traumatic.
Because any study has risks and because you won’t know all of the risks,
do not run a single participant without your professor’s permission.
To begin to
sensitize yourself to the risks involved in your proposed study, list the 10
worst things that could possibly happen to participants. If you are using human
participants, be aware that not all participants will react in the same way.
Some may experience trauma because the study triggers some painful memory. Some
participants may feel bad because they think they did poorly. Other
participants may feel bad because they think their behavior ruined your study.
Realize that some of your participants may be mentally unbalanced and any
attack on their self-esteem might lead to disastrous consequences. Because
participants are often fragile, you should list some serious consequences in
your worst-case scenario.
Because any study has the potential for harm, the possibility of severe
consequences does not mean that your professor will not allow you to do
the study. However, you and your professor should think about ways to minimize
the risks.
One method of minimizing risks is
to screen out “vulnerable participants.” For instance, if there is
any reason to believe that your study may increase heart rate or blood
pressure, you may want to make sure that only people in good health participate
in your study. If your study might harm people with low self-esteem, you may
want to use only well-adjusted participants who have high levels of
self-esteem. Therefore, you might give a measure of self-esteem to potential
participants to eliminate those with low self-esteem.
Not only should you screen
participants, but you should also let participants screen themselves. That is,
participants should be volunteers who give their informed consent:
They should know what the study is about before volunteering for it.
How
informed is informed consent? Very informed, when it comes to telling
participants about any unpleasant aspect of the study. If participants are
going to get shocked or exposed to loud noises or extreme cold, they should be
informed of this before they volunteer. Consequently, if your study does
involve unpleasantness, you may have difficulty getting participants to
volunteer.
Informed
consent is considerably less informed when it comes to more innocuous aspects
of the study. After all, the study would be ruined if participants knew
everything that would happen (and why it happened) before it happened. So,
although participants are usually told the truth, they are not always told the
whole truth. For example, a memory experiment’s description would mention
that participants have to memorize words, but might omit the fact that the
researcher is looking at the order in which facts are recalled or that there is
a surprise recall of all the lists at the end of the study.
Because
participants are not fully informed about your study, there may be some things
about it that they dislike. For example, suppose a participant finds the task
too difficult or finds it upsetting to try the surprise recall task. What
can you do?
One
protection against these unexpected problems is to make sure participants
understand that they can quit the study at any time. So, before the
participants begin your study, tell them that if they find any aspect of the
study uncomfortable, they can and should escape this discomfort by quitting the study.
Assure them that it is their duty to quit if they experience discomfort and
that they will still get full credit.
You have seen that you can minimize ethical problems by letting
participants know what they are in for and by letting participants gracefully
withdraw from the study. You should also minimize harm by making your study as
humane as possible. You can make your study more ethical by reducing the
strength of your treatment manipulation, carefully selecting stimulus
materials, and by being a conscientious researcher.
Although using extreme levels of
your predictor variable may help you get a significant change in the criterion
variable, extreme levels may harm your participants. For example, 24 hours of
food deprivation is more likely to cause hunger than 12 hours. However, 24
hours of deprivation is more stressful to the participant. If you plan an
unpleasant manipulation, remember your participants’ welfare and minimize
the unpleasant consequences as much as possible. Consider using levels of the predictor
variable that are less severe than you originally intended.
By modifying your stimulus
materials, you may be able to prevent them from triggering unpleasant memories.
For instance, if you were interested in the effects of caffeine on memory for
prose, you wouldn’t want the prose passage to cover some topic like
death, divorce, alcoholic parents, or rape. Instead, you would want to use a
passage covering a less traumatic topic such as sports. If the sports article
referred to someone’s death or hospitalization, you might want to delete
that section of the article.
Often, it’s not the study that causes ethical problems, it is the researcher’s arrogance.
For example, an arrogant researcher may rush through research sessions
providing only superficial explanations and almost no time for questions and
feedback. Although we know of a few participants who were hurt as a direct
result of a research manipulation, we know of many more who were hurt because the
researcher treated them like dirt. To ensure that you are sensitive, courteous,
and respectful to all of your human participants, you should do two things.
First, when
scheduling your research sessions, make sure you leave a 10-minute gap between
the end of one session and the beginning of the next session. Some
investigators feel that, like a physician, they should efficiently schedule
people one after another. Their “efficiency” results in
participants having to wait for the investigator, the investigator having to
rush through the formalities of greeting participants, or—even
worse—the investigator rushing through debriefing. Thus, the
“efficient” investigator, like the efficient physician, is seen as
unconcerned. Although this conduct does not become physicians, it’s
intolerable for psychological researchers! After a research participant has
given an hour of his or her time, you should be more than willing to answer any
questions the participant has. Furthermore, if you rush through greeting or
debriefing each participant, the participants will see you as uncaring.
Consequently, they will be less likely to tell you about any psychological
discomfort they felt and less likely to accept any aid you might offer. Thus,
the first step is to walk, rather than to run, participants through your study.
Second,
give the participants power. That is, allow participants to rate your study on
a scale such as the one in Table C–1. Give each participant’s rating sheet to your instructor.
Following this simple procedure helps you to be a conscientious and courteous
researcher.
Although you should try to anticipate and prevent every possible bad
reaction a participant may have to being in your study, you won’t be
successful. Inevitably, your procedures will still cause some unpleasantness.
After the study is over, you should try to remove this unpleasantness by
informing participants about the study, reassuring them that their reactions
were normal, and expressing your appreciation for their participation.
You should
also listen to participants and be sensitive to any unexpected, unpleasant
reactions to your study. By being a good listener, you should be able to undo
any damage you have unwittingly done. This process of informing your
participants about the study and removing any harm done is called debriefing.
Occasionally,
ordinary debriefing will not undo the harm caused to the research participant.
In those cases, there are several steps you may take to alleviate distress. For
participants who are upset with their responses, you should ask them whether
they want you to destroy their data. For participants that you cannot calm
down, you should take them to talk to a professor, counselor, or
friend—even if this means canceling a research session you had scheduled.
In summary,
you should be very concerned about ethics. Since ethics involves weighing the
costs of the study against the potential benefits, you should do everything you
can to minimize the risk of participants becoming uncomfortable. If, despite
your efforts, a participant experiences discomfort, you should try to reduce
that discomfort during debriefing.
With animal participants, you incur the same responsibilities that you
did with human participants—you must protect animal participants from
undue stress and discomfort. In many ways, you have even more responsibility to
animal participants because they depend on you for their mere existence. You
must keep them fed, clean, warm, and comfortable—24 hours a day. To fulfill
your responsibility to animal participants, you must follow APA’s
guidelines for proper housing, food and water, and handling (see Appendix A).
Furthermore,
because your animal participants do not have the power to give their informed
consent, nor the power to quit the study, you must carefully question the value
of your study. Ask yourself and your professor this question: “Is the
potential knowledge gained from the study worth the cost to the animals?”
Finally, if you must euthanize (kill) your animal participants at the end of
your study, follow APA’s guidelines to ensure that this is done in the
most humane way.
We have
discussed ways of minimizing harm to participants. However, minimizing harm is
not enough to ensure that your study is ethical. For your study to be ethical,
the potential benefits must be greater than the potential harm. Thus, an
extremely harmless study can be unethical if the study has no potential
benefits. So, just as you owe it to your participants to reduce potential harm,
you owe it to your participants to maximize the potential benefits of your
study. You maximize that potential by making sure your study provides accurate
information. To provide accurate information, your study needs to have power
and validity.
One of the
most serious obstacles to obtaining accurate information is lack of power.
Remember, null results don’t prove the null hypothesis. They only make
people wonder about the study’s power. There is no point in doing a study
that is so powerless that it will lead to inconclusive, null results.
To have
power, you should use a strong manipulation, a sensitive dependent measure,
well-standardized procedures, a sensitive design, and enough participants.
Perhaps
your most important obstacle to finding a significant effect is a lack of
participants. As a general rule, you should have at least 16 participants in
each group.[1] However, the number of participants you
need in each group will be affected by the sensitivity of your design, the
heterogeneity of your participants, the number of observations you get from
each participant, the size of the difference you expect to find between
conditions, and the sensitivity of your dependent measure.
If you have
a within-subjects design, a reliable and sensitive dependent variable, and
expect a rather large difference between your conditions, you may be able to
use fewer than 16 participants per group. If,
on the other hand, you are using a simple, between-subjects design,
heterogeneous participants, a manipulation that may have little effect, and a
relatively insensitive dependent measure, you may want at least 100
participants per condition.
Hunting
for Participants
How are you
going to get all the volunteer participants you need to conduct a powerful
study? The threat of death is not ethical.
The Draft
Some
researchers rely on “captive” samples. For example, many colleges
“volunteer” students in introductory psychology courses for the
research draft. In fact, most of the research strength of modern psychology has
been built using this research draft. If your school has such a draft, count
yourself among the blessed. All you have to do is ask your professor how to become
a recruiter.
Enlisting
Volunteers
If your
school does not have a draft, an effective way of getting participants is to
ask professors to request volunteers from their classes. Many professors will
gladly do this. Some will even give volunteers extra credit as an incentive for
participating in your study.
Noncollege
Samples
But what if
you don’t want to use college students in your study? For example,
suppose you want to study children or retirees? Or, suppose you agree with the
skeptics who claim that results from studies done on college students cannot be
applied to “normal people.” Then, you would look beyond college
classrooms for participants. A note of caution: You may find that getting
real-world participants takes as much work and creativity as planning your
study.
Children
If you want
to study children, you may be able to take advantage of the
“captive” audience approach. After all, most children have to go to
school. However, obtaining access to those children may turn into a nightmare
of red tape. You will have to obtain permission from all or many of the
following: the school board, the superintendent, principal, teacher, parent,
child, your professor, and university. If you are going to get these
permissions in time for your study, you’ll need to plan ahead—and
be very lucky.
Adults
Finding
adult participants can be even more challenging than finding children. For
example, one of your textbook’s authors wanted an adult population for
her doctoral dissertation. Her first thought was to contact a major company and
gain access to its employees. This tactic failed. Next, she tried to run a
newspaper ad asking for volunteers. One newspaper refused to print it. Another
would only run it in the “Personal” section. Thus, her appeal for
participants appeared with ads for astrological advice, massage services, and
people wanting dates. Although a few “volunteers” called, most
wanted either a date or an obscene conversation. We do not recommend newspaper
ads—especially if your goal is to get a representative sample of the
adult population.
The authors
have had greater success recruiting elderly participants. Nutrition centers,
retirement communities, friendship networks, and nursing homes have been
fruitful sources of participants. In addition, we recommend the
“grandmother connection”: having an older relative or friend
introduce you to other prospective participants.
Obviously,
finding human participants will take planning, perseverance, and luck. Once you
contact prospective participants, you should explain your study to them and
have them sign a permission form. The permission form will protect both you and
your participants. Basically, it states that you have explained the study to
the volunteers and that they agree to participate (see Table C–2). If minors are participating in
your study, you need to have separate forms for both the participants and their
parents.
Our
experiences with recruiting human participants might have increased your
enthusiasm for animal research. In many ways, animals are easier to study than
humans. You do not have to worry about permission slips, extra credit, or
obscene phone calls. Consult with your instructor about obtaining animals for
your research. Often, schools have rat colonies or purchase animals for student
research.
After
ensuring that your study has adequate power, we would like to be able to tell
you that you can take it easy and relax. Unfortunately, however, you
can’t relax. Power is not your only concern when conducting psychological
research. You must also ensure that the construct validity of your results is
not destroyed by
If you use more than one
investigator, you may be able to detect researcher effects by including the
researcher as a factor in your design. In other words, randomly assign
participants to both a condition and to a researcher. For example, if you have
two treatment conditions (A and B)
and two researchers (1 and 2), you would have four conditions: (1) A1,
(2) B1
(3) A2
and (4) B2. After having Research 1 run conditions 1 and 2 and
Researcher 2 run conditions 3 and 4, you could do an analysis of variance (ANOVA) using researcher as a
factor to see whether different researchers got different results.[2]
Using ANOVA
to detect researcher effects can be useful. However, there are at least two
reasons why using ANOVA may not eliminate researcher effects. First, this
statistical approach will only tell you if one researcher is getting different
results than other researchers. If all your researchers are biased, you may not
get a significant researcher effect. (Besides, if you are the only researcher,
you can’t use researcher as a factor in an ANOVA.) Second, and more
importantly, detecting researcher effects is not the same as preventing researcher
effects.
To prevent
researcher effects, you must address the three major causes of researchers
failing to conduct studies in an objective and standardized manner. What are
these causes? First, researchers may not know how to behave because the
procedures for how the researchers should conduct the study have not been
spelled out. Second, researchers may not follow those procedures. Third, the
researchers may strongly expect participants to behave in certain ways.
Often, the researchers
aren’t behaving in an objective and standardized way because of the loose-protocol
effect: The instructions aren’t detailed enough.
Fortunately, the loose-protocol effect can avoided.
Before you
start your study, carefully plan everything out. As a first step, you should
write out a set of instructions that chronicles the exact procedure for each
participant. These procedures should be so specific that by reading and
following your instructions, another person could run your participants the
same way you do.
To make
your instructions specific, you might want to write a computer program based on
these instructions. Since computers don’t assume anything, writing such a
program forces you to spell out everything down to the last detail. If you
can’t program, just write the script as if a robot were to administer the
study. Write out each step, including the actual words that researchers will
say to the participants. The use of such a script will help standardize your
procedures, thus reducing threats to validity.
Once you
have a detailed draft of your protocol, give it a test run. For example, to
ensure that you are as specific as you think you are, pretend to be a
participant and have several different people run you through the study using only your instructions. See how the
different individuals behave. This may give you clues as to how to tighten up
your procedures. In addition, you should run several practice participants.
Notice whether you change procedures in some subtle way across participants. If
so, adjust your instructions to get rid of this variability.
At the end
of your test runs, you should have a detailed set of instructions that you and
any co-investigator can follow to the letter. To double-check your protocol,
see Table C–3.
Unfortunately, even if you write
out your protocol (procedures) in detail, you or your
co-investigators may still fail to follow that protocol. To avoid the researcher
failure-to-follow-protocol effect, you need to make sure
that: (1) All investigators know the procedures, and (2) that everyone is
motivated to follow the procedures.
To make
sure that investigators learn the procedures, you should hold training
sessions. Supervise investigators while they practice the procedures on each
other and on practice participants.
Once
researchers know the right way to run the study, the key is to make sure that
they are motivated to run the study the same way every time. To increase
researchers’ motivation to be consistent, you might have them work in
pairs. While one researcher runs the participants, the other will listen in
through an intercom or watch through a one-way mirror. You may even wish to
record research sessions.
If your
researchers still have trouble following procedures, you may need to automate
your study. For instance, you might use a computer to present instructions,
administer the treatment, or collect the dependent measure. Computers have the
reputation for following instructions to the letter, so using a computer may
help standardize your procedures. Of course, computers aren’t the only
machines that can help you. Some of the machines that could help you give
instructions and present stimuli include automated slide projectors, tape recorders,
and videotape players. Countless other devices can be used to record your data
accurately, from electronic timers and counters to noise-level meters.
The final source of researcher
bias is the researcher-expectancy effect: Researchers’
expectations are affecting the results. You can take three steps to prevent the
researcher-expectancy effect:
1. Be very specific
about how investigators are to conduct themselves. Remember, researcher
expectancies probably affect the results by changing the investigator’s
behavior rather than by causing the investigator to send a telepathic message
to the participants.
2. Don’t let
the investigators know the hypothesis.
3. Don’t let
investigators know what condition the participant is in—making the
investigator “blind.” Although making investigators blind is easiest in
drug experiments where participants take either a placebo or the real drug, you
can make investigators blind in nondrug experiments.
For
example, if you present stimuli in booklets, you can design your booklets so
that booklets for different conditions look very similar. In that way, an
investigator running a group of participants might not know what condition each
participant is in. For some studies, you may be able to use a second
investigator who does nothing except collect the dependent measure. This second
investigator could easily be kept in the dark as to what condition the
participant was in.
Whether you
are the only investigator or one of a team of investigators, researcher effects
may bias your results. Therefore, you should always try to prevent the
loose-protocol effect, the failure-to-follow-protocol effect, and the
researcher-expectancy effect.
Unfortunately,
in psychological research, you must be aware not only of researcher effects,
but also of participant effects: Participants may see through the study and try to play
along with what the investigator wants. Fortunately, there are various ways of
preventing participants’ expectancies from biasing your results.
For
starters, you might make your researcher blind to reduce the chance that the
participant will get any ideas from the researcher. Thus, the techniques for
reducing research effects that we just discussed may also reduce the effects of
participants’ expectancies.
In
addition, you may also be able to prevent participants’ expectancies by
skillfully choosing your research design. In experimental investigations, for
example, you might use a between-subject design rather than a within-subject
design because participants who are exposed to only one treatment condition are
less likely to guess the hypothesis than participants who are exposed to all
treatment conditions.
Another
design trick you can use to reduce the impact of participants’
expectancies is to use placebo
treatments. Placebo treatments prevent participants from knowing that they are
in the “no-treatment” condition. Therefore, if you have comparison
condition(s), use placebo treatment(s) rather than no-treatment condition(s).
That way, all groups think they are receiving the treatment. Thus, any
treatment effect you find will not be due to participants changing their
behavior because they expect the treatment to have an effect.
Unobtrusive
Recording
Participants
are less likely to know the hypothesis if they don’t know what you are
measuring. Obviously, if they don’t even know they are being
observed—as in some field studies—they won’t know what you
are measuring. Thus, if your hypothesis is an obvious one, you might try to do
a field study.
Although
field studies lend themselves to unobtrusive recording, unobtrusive recording
can even occur in a laboratory study. That is, participants will assume that if
you are not in the room with them, you are not observing them. However, thanks
to one-way mirrors and intercoms, you can monitor participants’ behavior
from the next room.
Unobtrusive
Measures
Even if the
participant knows you are watching, the participant doesn’t have to know
what you are watching. That is, you can use unobtrusive measures. For example,
you might put the participant in front of a computer and ask the participant to
type an essay. Although the participant thinks you are measuring the
essay’s quality, you could have the computer programmed to monitor speed
of typing, time between paragraphs, number of errors made, and times a section
was rewritten. In addition, you might also have tape-recorded and videotaped
the participant, monitoring his or her facial expressions, number of
vocalizations, and loudness of vocalizations.
Rather than
trying to obscure or confuse participants as to the purpose of the study, you
might try to prevent participants from thinking about the purpose of the study.
How? By designing a study that has a high degree of research realism: a study that involves
participants in the task. Experimental realism means that participants
aren’t constantly saying to themselves: “What does the researcher
really want me to do?” or “If I were a typical person, how would I
behave in this situation?” Note that experimental realism doesn’t
mean the study is like real life; it means that participants are engrossed in
the task. In this age of video games, even a fairly artificial task can be very
high in experimental realism.
Ethics
Summary
Before now,
you might have been surprised to see experimental realism and other strategies
for reducing participant effects in a section on ethics. However, you now know
that planning an ethical study involves taking into account many factors. Not
only must you ensure the safety of your participants, but you must also
demonstrate the validity of your methods. To avoid overlooking an important
ethical consideration, consult Table C–4, Appendix A, and your professor.
Beyond the Proposal: The Pilot Study
Even after
you have carefully designed your study, modified it based on comments from your
instructor, and been given your professor’s go-ahead to run it, you may
still want to run several participants (friends, family members, other members
of the class) just for practice. By running practice participants, you’ll
get some of the “bugs” out of your study. Specifically, by running
and debriefing practice participants, you will discover
1. whether
participants perceived your manipulation the way you intended.
2. whether
you can perform the study the same way every time or whether you need to spell
out your procedures in more detail.
3. whether
you are providing the right amount of time for each of the research tasks and
whether you are allowing enough time in between tasks.
4. whether
your instructions were clear.
5. whether
your cover story was believable.
6. whether
you need to revise your stimulus materials.
7. how
participants like the study.
8. how long it takes
you to run and debrief a participant.
In short,
running practice participants helps you to fine-tune your study. Because
running practice participants is so useful, many professional investigators run
enough practice participants to constitute a small study—what researchers
call a pilot study.
Conducting the Actual Study
The dress
rehearsal is over. Final changes in your proposal have been made. Now you are
ready for the real thing—you are ready to “run” your study!
This section will show you how.
Establishing Rapport
As you may imagine, some of your prospective participants may be
apprehensive about the study. Participants often aren’t sure whether they
are in the right place, or even whether the researcher is a Dr. Frankenstein.
To put your
participants at ease, let them know they are in the right place, and be
courteous. You should be both friendly and businesslike. The expert
investigator greets the participant warmly, pays close attention to the
participant, and seems concerned that the participant knows what will happen in
the study. The expert investigator is obviously concerned that each participant
is treated humanely and that the study is done professionally.
Being
professional doesn’t hurt how participants view you. Why? First, most
participants like knowing that they are involved in something important.
Second, some will view your professionalism as a way of showing that you value
their time—which you should.
So, how can
you exude a professional manner? Some novice investigators think that they
appear professional when they act aloof and unconcerned. Nothing could be less
professional. Participants are very turned off by a disinterested attitude.
They feel that you don’t care about the study and that you don’t
care about them.
To appear
professional, you should be neatly dressed, enthusiastic, well-organized, and
prompt. “Prompt” may be an understatement. You should be ready and
waiting for your participants at least 10 minutes before the study is scheduled
to begin. Once your participants arrive, concentrate exclusively on the job at
hand. Never ask a participant to wait a few minutes while you socialize with
friends.
What do you
lose by being a “professional” investigator? Problem participants.
If you seem enthusiastic and professional, your participants will also become
involved in doing your study—even if the tasks are relatively boring.
Thus, if you are professional in your manner and attitude, you will probably
not even have to ask the participants to refrain from chatting throughout the
study. Similarly, if you are professional, participants will stop asking
questions about the study if you say, “I’ll explain the purpose at
the end of the study.”
After you
have established rapport, you need to give your participants instructions. To
get participants to follow instructions to the letter, you might take the
following six steps.
1. Be repetitive.
2. Have participants
read the instructions.
3. Orally paraphrase
those instructions.
4. Run participants
individually.
5. Invite
participants to ask questions.
6. Have participants
demonstrate that they understand the instructions by quizzing them or by giving
them a practice trial before beginning the study.
Once the
study has begun, try to follow the procedure to the letter. Consistently
following the same procedures improves power and reduces the possibility of
bias. Therefore, don’t let participants change your behavior by
reinforcing or punishing you. For instance, imagine you are investigating long-term
memory. You want
to expose participants to information and then see what they can write down.
However, if you do this, participants may be writing down information that is
in short-term memory. Thus, you would not be assessing long-term memory. Therefore, you add
a counting backwards task that should virtually eliminate all of the
information from short-term memory. Specifically, in your memory study,
participants are exposed to information, are supposed to count backwards from a
number like 781 by 3s for 20 seconds, and then are asked to recall the
information. Ideally, their recall will represent only what they have in
long-term memory. Unfortunately, many participants will and the counting task
unpleasant, embarrassing, or simply an unwanted nuisance. Consequently, some
participants will thank you for telling them they can stop; others will plead
nonverbally for you to stop. Clearly, you cannot let any of these strategies
stop you from making them count backwards for the full 20 seconds. If you vary
your procedures from participant to participant based on each
participant’s individual whims, your study will have questionable
validity.
Debriefing
Once the study is over, you should debrief your participants. In
debriefing, you should first try to find out whether the participants suspected
the hypothesis. Simply ask participants what they thought the study was about.
Then, explain the purpose of your study.
If you
deceived your participants, you need to make sure they are not upset about the
deception. You also need to make sure that they understand why deception was
necessary. Participants should leave the study appreciating the fact that there
was one and only one reason you employed deception: It was the only way to get
good information about an important issue.
Making sure
participants accept your rationale for deception is crucial for three reasons.
First, you don’t want your participants to feel humiliated or angry.
Second, if they get mad, they may not only be mad at you, but also at
psychologists in general. Perhaps that anger or humiliation will stop them from
visiting a psychologist when they need help. Third, the unhappy participant may
spread the word about your deception, ruining your chances of deceiving other
participants.
After
explaining the purpose of the study, you should answer any questions the
participants have. Although answering questions may sometimes seem like a waste
of time, you owe it to your participants. They gave you their time, now
it’s your turn.
After
participants’ questions and doubts have been dealt with, give them an
opportunity to rate how valuable they felt the study was. These ratings (1)
encourage you to be courteous to your participants; (2) let you know whether
your study is more traumatic than you originally thought; and (3) make participants
feel that you respect them because you value their opinions.
After the
rating, you should assure participants that their responses during the study
will be kept confidential. Tell them that no one but you will know their
responses. Then, ask the participants not to talk about the study because it is
still in progress. For example, you might ask them not to talk about the study
until next week. Finally, you should thank your participants, escort them back
to the waiting area, and say goodbye.
Protecting Data: Confidentiality
You might think that once a participant leaves the study, your
responsibilities to that participant end. Wrong! You are still responsible for
guaranteeing the participant’s privacy. Knowledge about a given
participant is between you (the investigator) and the participant—no
one else. Never
violate this confidentiality. To ensure confidentiality, you should take the
following five precautions:
1. Assign each
participant a number. When you refer to a given participant, always use the
assigned number—never that participant’s name.
2. Never store a
participant’s name and data in a computer—this could be a computer
hacker’s delight.
3. If you have
participants write their names on booklets, tear off and destroy the cover of
the booklet after you have analyzed the data.
4. Store a list of
participants and their numbers in one place and the data with the
participants’ numbers on it in another place.
[1] The more participants, the more
power. Indeed, some (Cohen, 1990) would consider 64 participants per group to
be a reasonable minimum. We have talked about minimums. Are there maximums?
Could you have a design that was too powerful? Some would argue that, in some
cases, researchers use so many participants that even the smallest of effects,
no matter how practically and theoretically insignificant, would be
statistically significant. However, having a design that is too powerful is
rarely a problem for novice researchers.
[2] You may want to consult with your
professor as to the type of ANOVA you should use. There is some debate as to
whether conventional ANOVA should be performed or a “random
effects” model should be used.
A guide from APA about conducting research for high school science projects (has some nice forms and examples for dealing with ethical issues--as well as some practical advice about planning and conducting research)