Deck 11: Understanding Statistics in Research

Question 1

In research,the probability that any data score will be within a certain range of a mean value is calculated based on the theory of:

A) frequency.
B) inference.
C) levels of significance.
D) the normal curve.

Answer 1

the normal curve.

Question 2

An appropriate level of significance for nursing research is either:

A) 0.5 or 0.1.
B) 0.03 or 0.003.
C) 0.05 or 0.01.
D) 0.005 or 0.001.

Answer 2

0.05 or 0.01.

Question 3

A researcher studies the effects of a nursing intervention on a desired patient outcome and discovers a statistically significant difference between groups receiving the intervention and those not receiving the intervention.The researcher concludes that the intervention is effective.This researcher has made a:

A) generalization.
B) statistical inference.
C) Type I error.
D) Type II error.

Answer 3

statistical inference.

Question 4

A researcher plans to apply a one-tailed test of significance when analyzing data from a study.Which is true about using this test?

A) The researcher will be unable to predict whether differences are greater than or less than the mean value.
B) This is a nondirectional hypothesis, so values will not have a tendency to vary in a specific direction.
C) This may increase the possibility of a Type I error when evaluating the significance of the findings.
D) This will decrease the possibility of a Type II error when drawing conclusions about the data.

Question 5

In statistical analysis of data,the alpha value is used to:

A) describe the degree of generalizability of the findings.
B) determine the risk of a Type I error.
C) reveal whether the p value meets criteria for statistical significance.
D) speculate on the frequency distribution of study values.

Question 6

A researcher evaluates the internal consistency (reliability)a newly developed scale used in a pilot study and notes a Cronbach alpha coefficient of space 0.72.The researcher will:

A) compare the measure with scores from another group of subjects.
B) test the scale for validity prior to using it in another study.
C) try another measure with better reliability in another pilot study.
D) use the scale in the larger study and continue to monitor coefficient results.

Question 7

When a researcher concludes that study findings are applicable to the total population,this is an example of:

A) generalization.
B) inference.
C) probability.
D) significance.

Question 8

In a discussion that includes the analysis of data collected during a pilot study,the researcher discusses the relationships and differences in data sets and makes predictions based on this analysis.The researcher will use which process?

A) descriptive analysis
B) inferential analysis
C) reliability testing
D) validity testing

Question 9

An important goal of inferential statistical analysis is to:

A) analyze and describe data collected during a study.
B) determine whether theoretical constructs are valid.
C) generalize results from the study to the target population.
D) measure the reliability and validity of measurement tools.

Question 10

After a clinical drug trial to measure the effects of atorvastatin administration on low-density lipoprotein levels,which of the following conclusion statements is acceptable in the research report?

A) Findings of clinical drug tests suggest that atorvastatin works to reduce low-density lipoprotein levels in study subjects.
B) Results of this clinical drug trial demonstrate that atorvastatin works to reduce low-density lipoprotein levels in all adults over age 65.
C) The negative correlation between atorvastatin administration and low-density lipoprotein levels indicates that atorvastatin causes a decrease in LDL levels.
D) The study proved that atorvastatin decreases low-density lipoprotein levels.

Question 11

A reviewer reads a research report and notes that the number of subjects in the original sample is larger than the number in the final analysis.Besides attrition of subjects,this discrepancy is likely because:

A) data from the control group are not included in the analysis.
B) essential data is missing from subjects no longer included.
C) subjects producing outlying data have been excluded from the results.
D) the final analysis usually discusses data from the experimental group only.

Question 12

It is important to know the demographic variables among study subjects in order to:

A) calculate central tendency and standard deviation of study scores.
B) ensure that control and experimental subjects are different.
C) ensure that outcomes are not caused by independent variables.
D) understand how well the sample represents the target population.

Question 13

Which describes an outlier?

A) A data point with a value outside what is predicted by other data points
B) Any data point far from the median point, but still within 2 standard deviations from the mean.
C) A study result that is directly attributable to randomness.
D) A study score from a subject lost to attrition after the study begins.

Question 14

When comparing a study with a level of significance of 0.05 with a study having a level of significance of 0.01,the researcher knows that the study with the level of significance of 0.05 is more likely to have a:

A) correct null hypothesis.
B) generalizable finding.
C) Type I error.
D) Type II error.

Question 15

Which of the following is not one of the components of power analysis?

A) Effect size
B) Error type
C) Power
D) Sample size

Question 16

A nurse conducts a study to evaluate the likelihood that single adolescent mothers will breastfeed their newborn infants if they are given materials about the benefits of breastfeeding.The results show a p value of 0.18.The nurse may conclude that:

A) the value is too low to be able to draw meaningful conclusions.
B) there is an 18% probability that this population will breastfeed their infants.
C) there is an 18% probability that this population will not breastfeed their infants.
D) there is an 82% probability that this population will breastfeed their infants

Question 17

Which situation will involve the use of inferential statistics?

A) A comparison of independent variables in a quasi-experimental study
B) A discussion about demographic data
C) An analysis of demographic variables of the target population
D) An examination of the differences between control and experimental group scores

Question 18

To measure test-retest reliability of an instrument,a researcher may use the:

A) Cronbach alpha coefficient.
B) Fischer's exact test.
C) Kuder-Richardson score.
D) Pearson's correlation statistic.

Question 19

What is the purpose of using exploratory analysis in a research report?

A) To compare control and experimental groups
B) To develop testable hypotheses
C) To examine and describe data
D) To identify theoretical constructs

Question 20

A researcher notes that 2 subjects in an experimental group had scores similar to those in the control group,while the other 20 experimental group subjects had scores far different from those in the control group.The researcher would consider the scores for the two subjects as:

A) control group findings.
B) outlier scores.
C) unexpected findings.
D) ungrouped participants.

Question 21

Assuming a normal distribution,what range of numbers would include two thirds of the scores if they ranged from 50 to 99,M = 75,and SD = 5? Between:

A) 55 and 95
B) 65 and 85
C) 68 and 82
D) 70 and 80

Question 22

A researcher conducts a power analysis for a study in which there was no difference between control and experimental group scores and identifies a power level of 0.75 and a level of significance of 0.05.What will this researcher do?

A) Alter measurement methods to detect larger changes in scores
B) Conclude that the null hypothesis is true
C) Consider repeating the study using a larger sample
D) Lower the level of significance to 0.01.

Question 23

A researcher studying subjects who have pulmonary disease presents a data set to describe the different conditions the subjects experience and reports the following data.Which number represents the mode for this data set?
Asthma 4
COPD 6
Chronic bronchitis 4
Pulmonary hypertension 7

A) 4.0
B) 5.25
C) 6.5
D) 7.0

Question 24

A researcher develops a study to examine the effects of Keep Yourself Safe Screening (KYSS)on the incidence of intimate partner violence (IPV).The study level of significance is 0.05.The null hypothesis,that KYSS will have no effect on IPV,is found to be true.When reviewing the study for Type II errors,the reviewer understands that:

A) a level of significance of 0.01 would decrease the risk of a Type II error.
B) the level of significance does not affect the chance of a Type II error.
C) there is a 5% chance that the null hypothesis is false.
D) there is a 5% chance that the null hypothesis is true.

Question 25

Which is true about the variance for scores in a data set?

A) A larger variance value usually indicates a smaller dispersion of scores.
B) It can be calculated for nominal scores.
C) The calculated score has no absolute value.
D) The variance indicates the range of scores.

Question 26

What is the mean value in the following set of scores?
A-128
B-128
C-130
D-135
E-144

A) 128
B) +128
C) 133
D) 132.8

Question 27

When a data set has a normal distribution curve,which statement is true about the data?

A) The mean is the lowest value.
B) The median is the highest value.
C) The mode is the central value.
D) The mode, median, and mean are equal values.

Question 28

A researcher will present demographic data about ethnicity,gender,and diagnoses about a study population using which method?

A) Continuous frequency distribution
B) Grouped frequency distribution
C) Percentage frequency distribution
D) Ungrouped frequency distribution

Question 29

Which is true about a sample that is heterogeneous?

A) It has a wide variation in scores.
B) Scores will be clustered around the mean.
C) The measure of range will be small.
D) The standard deviation cannot be calculated.

Question 30

In a data set that has a normal distribution what percent of scores will be within two standard deviations above or below the mean?

A) 34
B) 68
C) 95
D) 99

Question 31

A researcher collects scores measuring weight among school-age children who are in an obesity prevention program and notes that several students are morbidly obese with the majority of students falling within or below the 85th percentile for weight.The scores from the morbidly obese children will affect which measure of central tendency the most?

A) Mean
B) Median
C) Mode
D) All of the above are affected equally.

Question 32

A researcher collects the following scores on a set of ranked data.Which is the median score?
A-2
B-5
C-6
D-7
E-10
F-15
G-18
H-21

A) 7
B) 10
C) 8.5
D) 10.5

Question 33

The concept of degrees of freedom refers to:

A) the level of significance for a study.
B) the standard deviation from the mean among data.
C) the variability of a given score based on other scores.
D) whether statistical analysis is one- or two-tailed.

Question 34

A researcher conducts a study and calculates a mean value of 100 in a set of scores ranging from 90 to 300.Which other measure will the researcher report when describing central tendency in this data set?

A) Median
B) Mode
C) Range
D) Variance

Question 35

In a study to examine motivational techniques to help adolescent smokers to quit smoking,the null hypothesis states that the intervention will have no effect on this population.The researcher establishes a level of significance of 0.01.When analyzing the data,the researcher concludes that there is a significant difference between subjects receiving the intervention and those who do not.In this study,a Type I error means there is a:

A) 1% chance that the conclusion is wrong.
B) 1% chance that the conclusion is correct.
C) 99% chance that the conclusion is wrong.
D) 99% chance that the null hypothesis is correct.

Question 36

A researcher is analyzing the following data set.Which value represents the range?
A-43
B-46
C-46
D-57
E-67
F-69
G-78

A) 35
B) 46
C) 57
D) 58

Question 37

The median scores of two groups participating in a study are exactly the same for a particular variable.This suggests that the:

A) average score is the same for both groups.
B) the middle score is the same for both groups.
C) the most frequent score is the same for both groups
D) groups are very much alike in relation to the variable.

Question 38

Which describes the mode of a data set?

A) The appropriate measure of central tendency for interval data
B) The appropriate measure of central tendency for ordinal data
C) The exact center of scores for nominal data
D) The score value occurring with greatest frequency

Question 39

A researcher wishes to present data identifying pain scores for a group of subjects using a grouped frequency distribution table.Which is true about using this method?

A) Each group must have equivalent ranges in scores.
B) Ranges may overlap from one group to the next.
C) Some data may not fit into any group.
D) There should be no more than five groups of scores.

Question 40

Which is true about the measure of a data set's range?

A) It is an average score.
B) It is calculated using central scores.
C) It is determined only for interval level data.
D) It is sensitive to outliers in a data set.

Question 41

A review of demographic data shows that mothers with higher levels of education have fewer children.This represents which type of relationship?

A) Asymmetrical
B) Negative
C) Positive
D) Symmetrical

Question 42

Based on study data,a researcher predicts that a population mean will fall within a specific range of data.This is called the:

A) confidence interval.
B) range.
C) standard deviation.
D) validity measure.

Question 43

A researcher calculates a Pearson product-moment coefficient of 0.2.The reviewer understands that this value represents:

A) a moderate positive correlation.
B) a moderate negative correlation.
C) a weak positive correlation.
D) a weak negative correlation.

Question 44

A researcher conducts an experimental study on patients at different outpatient clinics,including clinics in inner city,suburban,and rural locations.To help ensure that differences in scores are not related to clinic location,the researcher will apply which technique?

A) ANOVA
B) ANCOVA
C) Bivariate correlation analysis
D) Factor analysis

Question 45

A data set is found to approximate a normal curve and has a mean of 72.5 and a standard deviation of 10.8.In which range of numbers will 99% of the scores fall?

A) 35.8 - 112.6
B) 44.6 - 100.4
C) 51.3 - 93.7
D) 61.7 - 83.3

Question 46

A researcher analyzes scores from two studies in which patients' temperatures were measured after antipyretic medications are given.One study measures temperatures in centigrade and the other in Fahrenheit.The researcher will:

A) calculate standard deviation measures for each study using their scale values.
B) compile all data regardless of scale and calculate measures of central tendency.
C) determine a Z-score and then calculate measures of central tendency.
D) realize that studies using different measures cannot be compared.

Question 47

A researcher has calculated a variance of 9 for a data set.What is this data set's standard deviation?

A) 1
B) 3
C) 4
D) 5

Question 48

A researcher presents data to examine the relationship between income and weight and uses a scatterplot to display the results.The researcher places income level intervals along the vertical line in the graph.The reviewer knows that:

A) data about income represent the independent variable
B) income data are presented along the X axis.
C) the plot will show whether the relationship is negative or positive.
D) weight values will occur along the Y axis.

Question 49

A researcher correlates self-confidence measures with obesity rates and determines an r value of 0.8.What can the reviewer conclude when evaluating this research?

A) There is a 36% chance that variation in one score is the result of variation in the other score
B) There is a 64% chance that variation in one score is the result of variation in the other score
C) There is a 64% chance that variation in one score is the result of variation in something other than the other score
D) There is a weak correlation between these two variables

Question 50

Clinicians now can calculate a person's myocardial infarction risk by evaluating several known risk factors,such as cholesterol levels and diabetes.This is possible because of:

A) bivariate correlation analysis
B) factor analysis.
C) multiple regression analysis.
D) simple linear regression analysis.

Question 51

Which is true about a Z-score?

A) It identifies the confidence interval for a group of data.
B) It is a method for calculating variance .
C) It is a standardized score used when data measures use different scales.
D) It represents the median data point in any set of data.

Question 52

Which is true about a correlational analysis technique?

A) It is most desirable for small samples with homogeneous scores.
B) It is used to determine cause and effect among sets of variables.
C) It measures the relationship among variables.
D) It usually involves comparing data from two subjects.

Question 53

In a study comparing weight gain between small-for-gestational-age (SGA)infants who were breastfed and SGA infants who were fed formula,researchers noted increased weight gain in infants who were held more regardless of how they were fed.This finding is an example of a:

A) mixed result.
B) nonsignificant result.
C) serendipitous result.
D) significant result.

Question 54

A review of demographic data shows that mothers with higher levels of education have fewer children.In this example,the r value is likely to be:

A) = 0.
B) <0.
C) >0.
D) not definable.

Question 55

What is true about the chi-square test of independence?

A) Chi-square test of independence results are important calculations in most studies.
B) In a relatively small sample size, the chi-square test of independence can reduce the chance of a Type II error.
C) The chi-square test of independence is a powerful test used to examine differences in studies with two subjects.
D) The chi-square test of independence is used to determine whether two variables are related or independent.

Question 56

Which circumstance will call for the use of analysis of variance (ANOVA)?

A) A researcher wishes to compare differences in means between four groups
B) A researcher wishes to compare the difference in variance between two groups
C) A researcher wishes to compare the difference in variance among four groups
D) A researcher wishes to compare the difference in correlation between two groups.

Question 57

A researcher wishes to display scores representing the relationship between two variables.Which will the researcher use?

A) Grouped data table
B) Pie chart
C) Scatterplots
D) Z-score