Mrs. Z Question and Answers
The minimal accepted level of significance for most research is:
.05
Which of the following is the only acceptable index for content validity (CVI)?
.92 the CVI must be above .90 to be acceptable.
In a normal distribution, ___________ % of scores fall within +/- 1 SD of the mean.
68
Sally obtained a score of 110 on a test. Test scores for all students were normally distributed (bell-shaped), with a mean of 100 and a standard deviation (SD) of 10. Approximately what percentage of students had a score lower than Sally?
84% : (50% had scores below the mean of 100 and 34% scored between the mean and 1 SD above it, i.e. between 100 and 110).
In a normal distribution, __________% of scores fall within +/- 2 SD of the mean.
95
In a normal distribution, __________% of scores fall within +/- 3 SD of the mean.
98
A researcher is comparing the bereavement and coping process of recently widowed and divorced individuals, controlling for their age. Which statistical test would you use to analyze this data?
ANCOVA
Variable 1 is patients' marital status (married vs. divorced, separated, or widowed vs. never married; Variable 2 is the patients' degree of self-reported depression (measured on a 30-item depression scale). Which statistical test would you use to analyze this data?
ANOVA
If a population were defined as "American men who have had lung cancer", one possible stratum would be:
American men over age 60 who have had lung cancer
The process of making sense of study results and of examining their implications happens during the ________________ phase of the quantitative process.
Analytical
The major problem with longitudinal designs is
Attrition
Variable 1 is the patients' gender; Variable 2 is whether or not the patient has experienced a myocardial infarct (MI) within the last two years. Which statistical test would you use to analyze this data?
Chi-squared
During this phase researchers call on such skills as creativity, deductive reasoning, and a grounding in existing research evidence on the topic of interest.
Conceptual
Hypotheses are formulated during the ___________________ phase of the quantitative research process.
Conceptual
Select the correct order of the Quantitative Process:
Conceptual-> Design/Planning-> Empirical-> Analytical-> Dissemination
________________________ is the preferred way to assess the extent to which a 30 item self-report measure is measuring mood state and nothing else, that is, that the scale is internally consistent.
Cronbach's alpha
In which phase does a quantitative researcher collect and code data?
Empirical
Another name for a randomized controlled trial is a(n):
Experiment
_______________________ is a statistical procedure which identifies clusters of related variables or items on a scale. Each cluster is a unitary attribute and is different from the others. This statistical procedure is an aspect of construct validity.
Factor analysis
Phase ________ of a clinical trial focuses on the development of a clinical intervention.
I
Phase ___ of a clinical trial has a small sample for a pilot test. This phase helps to determine the feasibility of a larger, more rigorous study and can help determine side effects of medications.
II
The act of drawing conclusions based on limited information using logical reasoning is known as:
Inference
To statistically test a hypothesis using a computer printout, determine if the results are significant or insignificant with a preset alpha level of .01. The computed p is .11
Insignificant
Psychological scales yield ___________- level measures.
Interval
The responses to a 33-item Likert Scale are summed - the level of measurement for the summed total is _______________-level measurement.
Interval
____________________ summarize the relationship between specificity and sensitivity in a single number.
Likelihood ratios
Which measure of central tendency is often used when variables are severely skewed?
Median
___________________statistical tests involve only ordinal or nominal level data and can only relate results to the study sample.
Non-parametric
"No relationship exists between participation in prenatal classes and the health outcomes of infants" is an example of which type of hypothesis?
Null hypothesis
____ focuses on a distinctive process of planning, developing, testing, and disseminating interventions. It requires careful, collaborative team planning.
Nursing Intervention Research
A response to a single Likert-scale item can be classified as a(n) _______________-level measurement.
Ordinal
This is a type of longitudinal study that gathers data from the same people at multiple points in time:
Panel
_____________________ statistical tests focus on population parameters and require measurements on at least interval data. This type is the most powerful and preferred approach because results can be generalized with more confidence.
Parametric
Variable 1 is the serum creatinine concentration levels; Variable 2 is daily urine output. Which statistical test would you use to analyze this data?
Pearson's r
__________________________ summarizes the degree of relationship between two variables.
Pearson's r
In a ____________________ there are typically between 50 and 100 cards to be sorted into 9 or 11 piles. Participants are asked to sort the cards along a specified bipolar dimension such as agree or disagree.
Q sort
__________________ is defined as the degree of consistency or dependability with which an instrument measures an attribute.
Reliability
"First-born infants have higher concentrations of estrogens and progesterone in umbilical cord blood than do later-born infants" is an example of which type of hypothesis?
Research hypothesis - directional
"The presence of homonymous hemianopia in stroke patients negatively affects their length of stay" is an example of which type of hypothesis?
Research hypothesis - directional
An instruments ability to identify a "case" correctly is its _________________________.
Sensitivity
To statistically test a hypothesis using a computer printout, determine if the results are significant or insignificant with a preset alpha level of .05. The computed p is .022
Significant
An instruments ability to identify a "non-case" correctly is its _______________________.
Specificity
Convenience sampling is to Quota sampling what Simple Random sampling is to _________________.
Stratified Random sampling
Which of the following is the title for a study that could not use an experimental design?
The effect of age on pulmonary complications in surgical patients - (researchers could not intervene w/ regard to participants age - this study would be non experimental.
Which purpose statement has correct (non-biased) wording?
The purpose of the study is to test the effects of an AIDS education workshop on teenagers' understanding of AIDS and the HIV virus.
This longitudinal design type collects data on different samples but the same population at repeated intervals.
Trend
A hypothesis is used to evaluate aspects of a theory and cannot test the theory because the theory is too abstract. If the hypothesis is confirmed then the theory is supported.
True
Internal validity threats are possible in quasi-experimental and correlational studies because these design types lack randomization, while internal validity is enhanced in experimental studies because randomization does occur.
True
Manipulation, Control, and Randomization are all necessary factors in an experimental design.
True
No one actually constructs a sampling distribution of the mean, it is a theoretical distribution used as a basis for inferential statistics.
True
Small samples may not detect relationships when relationships may really exist. Small samples also pose a threat to statistical conclusion validity.
True
With a 95% confidence interval (CI) around a sample mean of 50 = 45, 55 there is a 95% probability that the population mean lies within the lower limit CI of 45 and the upper limit CI of 55.
True
In factorial designs, there must be at least _______ independent variables.
Two
The extent to which an instrument is measuring what it purports (is supposed) to measure is known as:
Validity
Which of the following is NOT true?
a correlation between two variables is evidence that one caused the other
A researcher wants to test the difference between average blood pressures of a group of nursing home residents before and after a special intervention. What statistical test should be used?
a dependent t - test: for a single group before and after
What is random sampling?
a form of probability sampling
All citizens of Canada who are diabetic is an example of ___________________
a population
If a respondent completing a Likert Scale answered "strongly agree" to all items, this might be evidence of:
acquiescence bias and extreme response bias
A researcher used ANCOVA to compare the mean depression scores of men and women in two different racial groups (American Indian and Asian), holding constant their age. Which variable is the covariate?
age
One statistical method of controlling confounding variables is called a (n) __________________.
analysis of covariance
A researcher wants to assess whether a scale is really measuring emotional stability. The researcher compares the scores of 35 psychiatric patients and 35 people in the general population. What was the researcher doing?
assessing the construct validity of the scale (using the known-groups technique)
The reliability of measures of which of the following attributes would be best assessed using a test-retest (stability) procedure with one month between administrations:
attitudes toward abortion - this attribute is not likely to change within 1 month.
An experimental study had 152 participants randomized to a group receiving an intervention and 153 participants randomized to a control group receiving usual care. The new intervention was not pleasant to some participants in the experimental group and 41 of them dropped out of the study. This is a threat to the study's internal validity. What specific aspect of internal validity does this event fall under?
attrition/mortality
What is the main reason that researchers use samples rather than populations?
because it is more economical and efficient to work with samples
The process of preventing those involved in a study (participants, intervention agents, or data collectors) from having information that could lead to a bias (e.g., knowledge of which treatment group a participant is in) is known as:
both a and b
The measures must be high on this for the results of a study to be valid:
both reliability and validity: the measures must be reliable to also be valid.
In a cause and effect relationship, which is the independent variable?
cause - In causal relationships the independent variable is the cause, affecting the dependent variable
This type of probability sampling can be used when a sampling frame list is not available. Successive random sampling of units occur beginning with the largest group and works down to individuals.
cluster sampling aka multi-stage sampling
Criteria for cause and effect includes _________________, which is defined as similar evidence from multiple studies or sources.
coherence
A complete and thorough literature review is done at the beginning of the ________________ phase of the quantitative research process.
conceptual - a literature review done during this phase on all related research known about the topic and each variable (IV and DV).
Which would be an example of a Type II Error?
concluding that there are no post-treatment differences when in fact there are real population differences --- false null is accepted.
Which would be an example of a Type I Error?
concluding that there are post treatment differences between groups when in fact real population differences do not exist. --- true null is rejected!
Criteria for cause and effect includes ________________, which is defined as similar levels of statistical relationships in several studies.
consistency
Which type of validity is used to measure complex and highly abstract concepts, i.e. uncertainty?
construct validity
What type of validity is concerned with the adequacy of coverage of a topic area?
content validity
A ___________________ is a two-dimensional frequency distribution that can be used to describe relationships between two nominal level variables (i.e. gender and nurse specialty area).
contingency table
In experiments, those not getting the intervention are called the _______________________.
control group
A ___________________ presents correlations for multiple variables (3 or more), all measured on an interval or ratio scale.
correlation matrix
An analysis of threats to a study's validity is a way to address the _____.
credibility of results
Predictive validity and concurrent validity are aspects of ________________________validity.
criterion-related validity
A researcher studying the effects of length of nursing home residency on residents' emotional well-being compared 100 residents immediately after admission with 100 residents who had lived in the nursing home for 6 months. This is an example of a:
cross-sectional design
A design in which the same subjects are exposed to two or more conditions in random order is known as a ________________ design.
crossover
The purpose of this non-experimental design is to describe or explain relationships without causal connections. Ex.) How is quality of life related to depression level?
descriptive correlational
The purpose of this non-experimental design is to observe, describe, or document aspects of a situation. Ex.) How many children have ADHD in Montgomery county?
descriptive simple
Developing methods to safeguard human and animal rights take place during the ___________________ phase of the quantitative process.
design/planning
Deciding to collect data from 300 alcoholics in treatment would happen during which phase of the quantitative process?
design/planning - this phase includes identifying the population to be studied
Which of the following steps would NOT be undertaken in a non-experimental quantitative study?
developing intervention protocol
"Have you been hospitalized as an inpatient at any time in the last 5 years? □Yes □No" is an example of which type of question?
dichotomous
When strategies are concealed from those delivering an intervention and those receiving the intervention, the study is known as a ________________________ study.
double-blind
A(n) ________________________ summarizes the magnitude of an impact of the independent variable on the dependent variable.
effect size index
Distributing questionnaires to a group of nursing home residents would happen during which phase of the quantitative process?
empirical - this phase includes data collection from participants
Hypotheses usually appear at the:
end of the introduction section or immediately before methods section
A study's sample does not adequately represent the population. This is a threat to the study's _________________ validity.
external
The type of validity referring to the generalizability of results:
external
The type of validity involving the extent to which a measure "looks" valid is known as:
face validity
In addressing the ____________________, consideration is given to the characteristics of the study sample and the research setting.
generalizability of results
A _____________ threat occurs when other events happen at the same time as the independent variable.
history
Measures obtained within or on living organisms are ____________. Examples include BP, skin temperature, x-ray, and blood flow.
in vivo
The degree to which it can be inferred that the independent variable caused or influenced the dependent variable is known as ________________ validity.
internal
Another name for purposive sampling is:
judgmental sampling
The pairing of subjects in different groups as a method of controlling confounding variables is known as:
matching
Which measure of central tendency is often used for a normal distribution (bell-shaped)?
mean
Which of the following distributions of normally distributed scores is the most heterogeneous?
mean = 100 SD = 20
In assessing the degree to which the findings of a quantitative study are accurate and believable, which type of decisions would be especially important to critique?
methodological decisions
Effect size provides estimates about the magnitude of effects within a sample. A number (d) can show how powerful the effect of the IV on the DV. d of .54 would be considered a:
moderate effect
A threat to internal validity stemming from differential loss of subjects from groups is known specifically as a ___________________ threat.
mortality/attrition
A researcher wants to predict hospital staff absentee rates (number of days) based on staff rank, shift, number of years with the hospital and marital status). Which statistical test would you use to analyze this data?
multiple regression
As one's depression increases, self esteem then decreases. As one's self-esteem increases, depression then decreases. The relationship between depression and self-esteem may be said to be:
negatively correlated
(Graph Hill is to the right) This distribution would be considered:
negatively skewed
To statistically test a hypothesis, you must use an appropriate formula and determine the degrees of freedom. Then compare the test statistic to the tabled value. Determine if the following findings are statistically significant using a tabled value: calculated value = 2.05 tabled value = 2.10
non-significant
This design is almost identical to the before - after (pretest - posttest) experimental design. What makes it different is that subjects were not randomly assigned to groups.
nonequivalent control group before - after
Randomization (random assignment) is known as:
placement of participants to treatment conditions in a random manner, a manner which is determined by chance.
(Graph Hill is to the left) This distribution would be considered:
positively skewed
The quantitative procedure used by researchers to estimate how large a sample they need is known as a:
power analysis
Confidence intervals (CI) provide information about the __________.
precision of results
"Several factors have been found to be associated with pain and intensity during labor and delivery, but previous studies have produced conflicting results". This sentence could best be described as a:
problem statement - indicates a problem to be solved (identifying factors related to pain intensity) and a rational for new study (prior research inconclusive).
What is one advantage that mailed questionnaires have over personal interviews?
questionnaires offer the possibility of anonymity
Which correlation coefficient describes the strongest relationship?
r = -.75
The best way to control subject characteristics is to ____________________.
randomly assign participants to groups
Which of the following would NOT enhance a study's statistical conclusion validity?
randomly assigning subjects to treatment conditions
The number of kilograms a patient weighs is an example of __________________ because the values are ordered and equidistant and there is a rational zero.
ratio measurement
Errors of measurement contribute to inaccuracies and inconsistencies in measuring an attribute and thus lowering
reliability
A researcher wants to test the differences in average heart rates when a group of elderly participants is exposed to 3 different methods of stimulation administered to them in random order. Which statistical test should be used?
repeated measures ANOVA
This type of non-experimental design starts with an observed condition in the present and looks backwards for the cause.
retrospective (case-control)
In a sampling distribution of the mean, the standard error of the mean gets smaller (estimates of the mean get more accurate) as...:
sample size gets larger
A threat to internal validity stemming from pre-existing group differences is known specifically as a ________________ threat.
selection
Respondents are asked to rate concepts (e.g., dieting, exercise) on a series of bipolar adjectives, such as good/bad, effective/ineffective, or important/unimportant. They place a check at the appropriate point on a seven-point scale that extends from one extreme to the other. This technique for measuring attitudes is known as:
semantic differential
To statistically test a hypothesis, you must use an appropriate formula and determine the degrees of freedom. Then compare the test statistic to the tabled value. Determine if the following findings are statistically significant using a tabled value: calculated value = 2.86 tabled value = 2.10
significant
Researchers studying PTSD among soldiers obtain a sample by asking participants for referrals to other soldiers who have been known to experience traumatic events during combat. This is an example of:
snowball sampling
The _____________________ is the most widely used measure of variability
standard deviation
A weight scale being used in a study in is not calibrated correctly. It weighs each participant 4 kilograms more than their actual weight. This type of error would be known as a:
systematic error
A researcher studying the exercise habits of university students samples every 30th student on an enrollment roster. This is an example of:
systematic sampling
Variable 1 is the participation vs. nonparticipation of patients with diabetes in a special treatment group. Variable 2 is the patients' blood glucose reading. Which statistical test would you use to analyze this data?
t-test
A criterion for inferring causality is a lack of _________________. This is usually not a problem in experimental designs.
temporal ambiguity
One disadvantage of the crossover design is:
that carryover effects may occur from one treatment to the next
What is a major advantage of using random sampling?
the resulting sample has a greater likelihood of being representative than when nonrandom sampling is used
If a scale is not reliable, which of the following is true?
the scale cannot be valid
A 95% confidence interval (CI) around a sample mean of 120 = 105, 135. Which of the following is true?
there is less than a 5% chance that the population mean is 140
What do matching, randomization, and homogeneity have in common?
they are methods of research control over subject characteristics
A quasi-experimental design involving the collection of data multiple times over an extended period.
time series
The __________________ can never really be known, it is the hypothetical perfect score.
true score
The _____________________ is used to measure subjective experiences such as pain, fatigue, and dyspnea. It is a straight line 100 mm in length. Participants mark a point on the line corresponding to the amount of sensation experienced.
visual analog scale
In crossover designs, subjects are exposed to more than one experimental condition in random order and serve as their own controls; such designs are _________________ designs.
within-subjects