IVs, DVs, and Designs, Oh My

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IVs, DVs, and Designs,Oh My!

• Psychological Research Methods

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General Information

• All studies measure something
• Correlational and Descriptive studies
• No IV
• No subject variable
• If there is a true IV, then the study is
  experimental, even if there is also a subject
  variable

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General Information

• If a study has only subject variables, then it is
  quasi-experimental
• A characteristic of the subjects
• is a subject variable if there are two or more
  levels
• with only one level (i.e., all participants have
  the characteristic) then the characteristic is
  simply describing the population

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General Information

• Levels of Measurement (p. 71-72) is different
  than levels of an IV or subject variable (p. 156)

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Cross-national research is plagued by many
obstacles. This article focuses on one of these
obstacles the fact that research in more than
one country usually involves respondents with
different native languages. We investigated
whether the language of the questionnaire
influences response patterns. More specifically
we tested whether responding in a common language
(English) leads to a homogenization of responses
across countries, hence obscuring national
differences. We tested this hypothesis with a
sample of 3419 undergraduate students in 24
countries. Half the students in each country
received an English-language questionnaire, while
the other half received the same questionnaire in
their native language. Three types of questions
were included in the questionnaire questions
about cultural norms and values, questions about
characteristics of the ideal type of jobs that
students would prefer after graduation, and
questions about the reasons for choosing
particular electives in their studies.
(Harzing, 2005)
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Comparisons with counterfactual outcomes can
influence choices in sequential decisions. We
examine the effect of anticipated regret, and
"social takeover" the knowledge that someone
else might take over an investment one has
abandoned on persistence on an investment task.
Some participants received feedback about what
would have happened if they had continued
investing and others did not. Some knew that
another person had the opportunity to pick up
their investment where they left off and others
did not. Data collected from 84 dyads showed
effects of both experimental manipulations.
Participants invest longer, on average, when
another person could take over from their
previous investments, and when feedback was
provided. Both anticipated regret and social
takeover appear to increase the tendency to stick
with an investment. (Hoelzl, Loewenstein, 2005)
7
Although the number of studies on research
utilization is steadily growing, there are only a
few specialty-specific studies. This study
focuses on medical and surgical nurses. It
compares their reported use of research
utilization and their perceptions of barriers and
obstacles. A convenient sample of 210 medical
nurses and 269 surgical nurses, from 10 general
hospitals in 14 Trusts in Northern Ireland (NI),
was surveyed. The results showed that the
reported extent of research utilization was high,
with less than 10 in each group reporting
never/seldom using research. The reported
difference between the medical and surgical
nurses was very small, with medical nurses
reporting a slightly higher rate of utilization.
However, this was not statistically significant
at 5 level. The Barriers Scale (Funk et al.,
1991) used in this study to assess their
perceptions of barriers and facilitators revealed
a similar picture for both groups. (Parahoo,
McCaughan, 2001)
8
This study investigates 35 students' with mild
learning disabilities reactions to participating
in a research project exploring their sexual
knowledge, attitudes and behaviour. Students
completed an informed consent procedure prior to
their participation in the sexuality research and
all were interviewed using a confidential
interview procedure. During the research
interviews, each student's reaction to
participation was observed and recorded by their
interviewer. Following the interviews, each
student's reaction to participation was observed
and recorded by their college tutor. Researchers
observed that although some students were
embarrassed discussing certain sexual topics,
none chose to stop their interviews when invited.
Ten students requested additional information
from their interviewers about the issues
discussed. Tutors reported (Thomas, Kroese,
2005)
9
Previous deception detection training studies
This paper tests the speculation that the simple
act of training, independent of the training
content, may improve accuracy simply because
those in training conditions process messages
more critically. This speculation was tested in
three studies that included both no training and
bogus training control groups. The bogus training
group was most accurate in Study 1, but this
finding failed to replicate in Study 2. A coding
study (Study 3) examined behavioral differences
in the stimulus tapes. The predicted differences
were observed in a final experiment (Study 4)
where training was based on the coded stimulus
tapes. The results suggest that the effects of
training are generally small and highly variable
from message to message, that valid training does
not produce large improvements over a bogus
training control, and that bogus training can
produce statistically significant improvements
over a no-training control. (Levine, Freeley,
McCornack, Hughes, Harms, 2005)
10
We examined the process of obtaining "active,"
written parental consent for a school-based
HIV/AIDS prevention project in a South African
high school by investigating (1) parental consent
form return rates, (2) parents' recall and
knowledge of the research, and (3) the extent to
which this consent procedure represented parents'
wishes about their child's involvement in the
research. This study comprised interviews with
parents of children in grades eight and nine in a
poor, peri-urban settlement in Cape Town. Within
2 weeks, 94 of 258 parents responded to a letter
requesting written consent and of those, 93
consented, but subsequent interviews showed that
65 remembered seeing the consent form. At the
end of the interview, 99 consented to their
child's participation. These findings challenge
(Mathews, Guttmacher, Flisher, Mtshizana, Hani,
Zwarenstein, 2005)
11
To compare IRB processes in 68 U.S. hospitals
for the same multicenter study we surveyed IRB
processes in 68 U.S. hospitals during 2001-2002.
Requirements of IRB submission including type and
duration of review and qualifications of
principal investigator were compared by hospital
bed size, region, and academic affiliation. The
majority of hospitals. About one-third (33.8)
required. Mean number of pages for the
application was 5.24 (1-31) and up to eight
copies were requested. Time from submission of
the IRB application to approval averaged 45.4
days (range, 1-303 days), and the majority of
reviews were "expedited" (61.8). Expedited
reviews required more time (mean, 54.8 days) than
did either exempt (mean, 10.8 days) or full
(mean, 47.1 days) reviews. Current IRB review
processes are cumbersome and nonstandardized, and
review time varies widely. (Larson, Bratts,
Zwanziger, Stone, 2004)
12
Despite its potential relevance to the treatment
of drug abuse, conditioned inhibition of drug
seeking has not been systematically investigated
before. In this study, rats could self-administer
cocaine by lever pressing whenever a click or
tone was present. Responding was not reinforced
when a light was present. The light was presented
simultaneously with the click (i.e., in an
excitatory context) in 1 group, but the light was
always presented alone in another group. When it
was later presented in compound with the tone,
the light was a highly effective conditioned
inhibitor, suppressing cocaine seeking by 92 in
the former group and by 74 in the latter. These
results suggest ways to improve cue-oriented
behavioral treatments for drug abuse. (Kearns,
Weiss, Schindler, Panlilio, 2005)
13
Face composite programs permit eyewitnesses to
build likenesses of target faces by selecting
facial features and combining them into an intact
face. Research has shown that these composites
are generally poor likenesses of the target face.
Two studies tested the proposition that this
composite-building process could harm the
builder's memory for the face. In Study 1 (n
150), the authors used 50 different faces and
found that the building of a composite reduced
the chances that the person could later identify
the original face from a lineup when compared
with no composite control conditions or with
yoked composite-exposure control conditions. In
Study 2 (n 200), the authors found that this
effect generalized to a simulated-crime video,
but mistaken identifications from target-absent
lineups were not inflated by composite building.
(Wells, Charman, Olson, 2005)
14
The roadside crossing judgments of children aged
7, 9, and 11 years were assessed relative to
controls before and after training with a
computer-simulated traffic environment. Trained
children crossed more quickly, and their
estimated crossing times became better aligned
with actual crossing times. They crossed more
promptly, missed fewer safe opportunities to
cross, accepted smaller traffic gaps without
increasing the number of risky crossings, and
showed better conceptual understanding of the
factors to be considered when making crossing
judgments. All age groups improved to the same
extent, and there was no deterioration when
children were retested 8 months later. The
results are discussed in relation to theoretical
arguments concerning the extent to which
children's pedestrian judgments are amenable to
training. (Thomson, Tolmie, Foot, Whelan,
Sarvary, Morrison, 2005)
15
When people discuss their memories, what one
person says can influence what another person
reports. In 3 studies, participants were shown
sets of stimuli and then given recognition memory
tests to measure the effect of one person's
response on another's. The 1st study (n 24)
used word recognition with participant-confederate
pairs and found that the effect of confederate
responses on participant responses was larger for
previously unseen items than for previously seen
items (?p .23). This finding was replicated in
the 2nd study, which used photographs of cars (n
24). In the 3rd study (n 54), which used
photographs of faces with participant pairs, the
effect was also larger for unseen items. Results
indicate that people rely more on other people's
memories for unremembered objects than for
remembered objects. This is important for both
theories of memory and applications (e.g.,
witnesses talking, students studying together).
(Wright, Mathews, Skagerberg, 2005)
16
This study showed that the values power
(dominance over nature and resources) and
universalism (respect for people and for nature)
are related to attitudes toward genetically
modified food (GMF) and organically grown food
(OGF). Furthermore, these values have an
influence on the centrality, commitment and
ambivalence of these attitudes. Values that are
positively related to an attitude influence how
central this attitude is to a person. However,
values that are negatively related to an attitude
have a larger effect on the commitment of this
attitude. No such pattern of effects was found
for the relationship between ambivalence and
values. These data suggest that centrality,
commitment, and ambivalence are structurally
different constructs that have a distinct
relationship with specific values. (Dreezens,
Martijn, Tenbült, Kok, de Vries, 2005)
17
Leptin deficiency has been associated with
extreme obesity and hyperphagia in rodents and
humans. A rare genetic disorder in humans yields
the absence of the hormone leptin, extreme
obesity, and a ravenous appetite. Reports on
these rare cases have indicated that therapy
using leptin injections can yield significant
weight loss and changes in appetite. The aim of
this report on acute leptin therapy in three
leptin deficient adults was to provide a
microanalysis of changes in eating behavior and
ratings of hunger and satiety. In addition to
substantial weight loss, 15 weeks of leptin
therapy was associated with approximately 50
reduction in food intake and substantial changes
in ratings of hunger and satiety before most
meals. After short-term leptin therapy, the three
participants ate until ratings indicated they
were satiated, which was comparable to the
ratings before leptin therapy. These findings
suggest. (Williamson et al., 2005)
18
The objective of this study was to conduct a
preliminary evaluation of an Internet-based
intervention for problem drinkers, comparing
changes in drinking between respondents who only
received the intervention to those who also
received a self-help book. After receiving a
personalized feedback summary on the Internet, 83
respondents provided complete baseline
information and volunteered to participate in a
3-month follow-up survey. Half of the respondents
were randomized to receive an additional
self-help book. The follow-up was returned by 48
respondents (69 female). Repeated measures
ANOVAs. There was minimal support for an impact
of the Internet intervention alone. Respondents
who received the additional self-help book
reported drinking less and experiencing fewer
consequences at follow-up as compared to
respondents who received only the Internet-based
intervention. While the results are promising.
(Cunningham et al., 2005)
19
Adolescent stress is an emerging area of
importance. The aim of this study was to
determine the effectiveness of progressive muscle
relaxation (PMR) for anger in stressed male
adolescents. A random sample of 252 subjects was
recruited. Increased Anger-Out scores were found
in 81 of them on entry to the study. PMR was
employed for 8 weeks for a randomly selected
group of 40 of the 81, while the other 41 formed
the control group. The salivary cortisol
concentration, State-Trait Anger Expression
Inventory (STAXI), and Health Survey (SF-36) were
used in the study. Initial examination revealed
raised salivary cortisol levels on awakening,
increased scores on most of the STAXI scales and
relatively low T-values on the SF-36 scales,
which describe physical health. At the highest
morning salivary cortisol concentration (p lt
0.01). (Nickel, Lahmann, Tritt, Loew, Rother,
Nickel, 2005)
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This study investigates the relationship of
emotional intelligence (EI) characteristics, such
as perception, control, use and understanding of
emotions, with physical and psychological health.
In the first study, 365 individuals filled in
measures of EI and general health. It was
hypothesized that EI would be negatively
associated with poor general health. In the
second study, 212 working adults completed the
same measure of EI and another measure, which
apart from the standard information regarding
physical and psychological health, provided also
information about other health related
behaviours, such as smoking, drinking, and
exercising. It was also hypothesized that EI
would negatively correlate with smoking and
drinking and positively correlate with
exercising. The findings confirmed both
hypotheses and provided further support on the
claims that there is a relationship between EI
and health functioning. Additionally.
(Tsaousis, Nikolaou, 2005)