NSG-522 Midterm

Outliers can be identified using a (SELECT ALL THAT APPLY) a. Box-and-whisker plot with Tukey Fences. b. Histogram. d. Stem-and-leaf plot. e. Bar chart. f. Any/all of the above

A. Box and whisker plot with Turkey fences

What percentage of scores fall between the first and third quartile? 25% 50% 68% 75% 100%

50%

What percentage of observations fall within +/- 2 standard deviations of the mean? 25% 50% 68% 95% 99%

95%

A researcher determines that the results of a hypothesis test are statistically significant. This means that the p-value from the test is >.05 <.025 or >.975 >.95 <.05

<.05

An R-value of 0.33 indicates A moderate relationship between the variables A statistically significant relationship between the variables the null hypothesis should be rejected there is no relationship between the variables

A moderate relationship between the variables

A Pearson correlation coefficient is 0.04. This correlation indicates that there is A statistically significant relationship between the variables A moderate, positive relationship between the variables A strong relationship between the variables A very weak relationship between the variables

A very weak relationship between the variables

When comparing pain scores measured on a scale from 1-10 in the same patients before and after receiving a new pain medication, the researcher should use which of the following tests A Mann Whitney test A Wilcoxon signed-rank test A Mcnemar test A paired t test

A wilcoxon signed rank test

A clinical nurse leader on the surgical intensive care unit compares two interventions for reducing the number of SSI's. A statistical test comparing the number of infections in each group yields p-value of .049. This value indicates that A. There is a statistically significant difference between the groups B. There is a risk of type 2 error C. There is not a statistically significant difference between the groups D. There is not enough information presented to interpret the findings.

A. There is statistically significant difference between the groups.

A study can only have one dependent variable

False

When alpha is set at .05, only p-value of <.05 or >.95 are statistically significant

False

The quality of life is measure on a scale of 1 (extremely poor quality) to 5 (best possible quality). The best graphic display of these measurements would be a Bar chart Stem and leaf plot Box and whisker plot Histogram

Histogram

What type of graphic display would be the best for a variable measured at the ordinal data?

Histogram

When comparing hemoglobin A1C measurements that re normally distributed with no outliers in 2 independent groups, the researcher should use which of the following? Fisher exact pearson correlation independent t test kruskal-wallis ANOVA

Independent t test

In a box and whisker plot, the length of the box is equal to the Midrange Epidemiological range Statistical range Interquartile range

Interquartile range

The operational definition of a variable

Specifies how a variable should be measured

Height recorded in centimeters should be displayed using. SELECT ALL THAT APPLY Bar chart Box and whisker plot Stem and leaf plot Histogram

Box and whisker plot Stem and Leaf plot Histogram

The epidemiological range is

the minimum and maximum values

The dependent variable

the outcome variable

The most frequently occurring number in a set of numbers is the a. Median b. Mode. c. Midrange d. Frequency e. 50th percentile

b. mode

Testing a new piece of equipment to ensure that the equipment consistently provides that same measurement when the same variable is measured multiple times is an example of Accuracy Validity Reliability All of the above

Reliability

Which of the following are parametric test? SELECT ALL THAT APPLY Repeated measures ANOVA Paired t-test McNemar Test Pearson correlation coefficient Wilcoxon signed-rank test

Repeated measures ANOVA Paired t-test Pearson Correlation Coefficient

Differences between the characteristics of a sample and the characteristics of the population of interest are due Sampling error Random error Measurement error Systematic error

Sampling error

A clinical nurse specialist is comparing two post op pain management strategies to determine whether there is a difference between the 2 strategies in cost of care, length of hospital stay, and patient satisfaction with care. Which of the following is/are dependent variables in this study? Satisfaction with care Cost of care Pain management strategy Clinical Nurse Specialist Length of hospital stay

Satisfaction with care Cost of care Length of hospital stay

Which of the following would be reasons for using a nonparametric test? SELECT ALL THAT APPLY interval level data Shapiro-wilk test p-value of 0.010 Presence of one small outlier Normal distribution Nominal level data

Shapiro-Wilk test p-value of 0.010 Presence of one small outlier Nominal level data

A researcher studies the relationship between the number of minutes of breast pumping and the amount of milk produced per day in mothers of preterm infants. The R-squared value is 0.49. This finding means that There is not a statistically significant relationship between the variables There is a moderate positive relationship between the variables The number of minutes of pumping explains 49% of the variance in milk output There is not enough information to determine whether there is a meaningful relationship between the variables

The number of minutes pumping explains 49% of the milk output

Which of the following p-values is/are statistically significant when alpha is set at 0.05? SELECT ALL THAT APPLY 0.0Q0 0.410 0.999 0.100 0.500

0.010

A researcher studies the relationship between hours of television watching and BMI. The correlation coefficient is .35 which indicates A moderate inverse relationship A weak positive relationship A strong positive relationship A moderate positive relationship

A moderate positive relationship

A sample is... A. Selected from the population of interest using a random process B. Best selected by using a nonprobability sampling methods C. A subset of the population of interest D. Best selected by using a purposive sampling

C. A subset of the population of interest

A small sample size A. Increases the risk of both type 1 and type 2 errors B. Has no effect on the results of a statistical test C. Increases the risk of a type 2 error D. Increases the risk of a type 1 error

C. Increases the risk of a type 2 error

The best way to determine whether data are normally distributed is to A. Construct a box and whisker plot with turkey fences B. Construct a histogram C. Perform a shapiro-wilk test D. Perform a test for outliers

C. Perform a shapiro wilk test

When alpha is set at .05, that means that A. There is a 95% chance of making a type 2 error B. Only p-values >.05 are statistically significant C. There is a 5% chance of making a type 1 error D. There is a 5% chance of incorrectly accepting the null hypothesis

C. There is a 5% chance of making a type 1 error

An analysis of variance results in p-value of 0.50. The researcher should conclude that A.There is a statistically significant difference between the groups. B. The results are clinically significant C. There is not a statistically significant difference between the groups D. The sample size was too small

C. There is not a statistically significant difference

When testing for a relationship between 2 independent, nominal variables, the best test to use would be a/an Independent t-test Pearson correlation coefficient Chi-square test Spearman correlation coefficient

Chi-square

Which of the following are nonparametric tests? SELECT ALL THAT APPLY Chi Square test Dependent t test Spearman correlation coefficient One-way analysis of variance Mann-whitney test

Chi-square test Spearman correlation coefficient Mann-Whitney test

A conceptual definition defines how a variable will be measured, and includes the equipment and procedures that are used in the measurement

False

A student conducting a quality improvement project on a unit in the university hospital where the student is enrolled. Since the project is required by the university, the student does not need to obtain additional permission for the project

False

A type 2 error occurs when the researcher concludes that there is a statistically significant difference between the groups when there really is no difference

False

Bar charts and histograms can both be used to describe interval level data

False

If a hypothesis test identifies a statistically significant finding, that means that the finding is clinically significant and should be implemented into clinical practice as soon as possible

False

Nonprobability samples are selected using a random process

False

P values vary from 0-1.0 and can be positive or negative

False

Parametric tests can be used to analyze ordinal variables but not nominal variables

False

The frequency and relative frequency presented as a percentage should both be reported when describing interval level data

False

The interpretation of a p-value varies depends on what statistical test was used to obtain the p-value

False

The mean is the number in the middle of the observations, when the observations are arranged from smallest to largest.

False

The standard error of the mean is a measure of the spread of observations around the mean of the observations

False

The validity of a weight measurement obtained with an electronic scale refers to the repeatability of the measurement

False

When a continuous variable has a normal distribution and only 1 small outlier, the mean and standard deviation should be used to describe the variable

False

the 95% confidence interval for the mean of a set of observations indicates that 95% of the observations fall within the confidence interval

False

The best test to use when testing for a relationship between 2 dichotomous, independent variables would be a McNemar Test Chi-square test Independent t-test Fisher Exact test

Fisher Exact test

A researcher is comparing the outcome variable of cost in US dollars in 3 independent groups. The data are normally distributed without outliers. The researcher should use which of the following tests to compare 3 groups? Chi-square test One-way ANOVA Kruskal-Wallis test Friedman test Repeated measures ANOVA

One-way ANOVA

When comparing ratio level variable that is normally distributed and without outliers in 3 different groups of patients, which statistical test should be used Kruskal-Wallis ANOVA Friedman test Chi-square test One-way ANOVA

One-way ANOVA

a variable was coded as disease present, disease not present, or disease status unknown. When performing the descriptive statistics, which of the following should be used? SELECT ALL THAT APPLY Median Percentages Proportions Frequencies Mode

Percentages Frequencies

When analyzing the variable gender, which was measured in 5 categories- the data should be displayed using a histogram box and whisker plot pie chart bar chart line chart

bar chart

A 95% confidence interval for a mean indicates A. 95% of the observations are located within the interval B. there is a 95% chance that the finding is statistically significant C. We can be 95% confident that the true population mean lies within the interval D. All of the above

c. We can be 95% confident that the true population mean lies within the interval

clinical data conducted can be shared to a cloud for all involved researchers to share/view

false

Which of the following sampling methods would provide the best representation of a population with the following racial compisition: 68% white, 15% African American, 12% Hispanic, 5% Asian Cluster sample Simple random sample Quota sample Stratified random sample

stratified random sample

Which of the following samples would provide the best representation of a population A. A nonprobability sample B. A quota sample C. A simple random sample D. A convenience sample

C. A simple random sample

The decision to use the mean or median is based upon (Select all that apply) A. Whether the data are normally distributed b. Which statistical tests will be used for hypothesis testing c. The presence or absence of outliers d. The guidelines of the journal where the data will be published

A. Whether the data are normally distributed B. The presence or absence of outliers

When performing a hypothesis test, a type 2 error occurs when the researcher incorrectly A. Accepts the alternative hypothesis B. Concludes that the findings are not statistically significant C. Rejects the null hypothesis D. Concludes that the findings are statistically significant

B. Concludes that the findings are not statistically significant

When performing a hypothesis test to compare groups, a type 1 error is made when a researcher A. Rejects the alternative hypothesis B. Concludes that there is a significant difference between groups when there really is not a difference C. Accepts the null hypothesis D. Concludes that there is not a statistically significant difference when there really is a difference

B. Concludes that there is a significant difference between groups when there really is not a difference

A p-value 0.50 from a Spearman Correlation Coefficient would indicate that there is A. A strong relationship between the variables B. Not a statistically significant relationship between the variables C. A moderate, positive relationship between the variables D. A statistically significant relationship between the variables

B. Not a statistically significant relationship between the variables

A 95% confidence interval for the mean of a set of height measurement is 62.9 and 64.5 inches. This finding means that A.There is a 5% chance of a type 1 error B. We can be 95% confident that the true populations mean is between 62.9 and 64.5 inches C. The confidence interval is not statistically significant D. 95% of the observations in the data set are between 62.9 and 64.5 inches.

B. We can be 95% confident that the true populations mean is between 62.9 and 64.5 inches

Which of the following can be determined from a Spearman correlation coefficient and its associated with p-value? SELECT ALL THAT APPLY Statistical significance Risk of a type 2 error Strength of the relationship Direction of the relationship

Statistical significance Strength of the relationship Direction of the relationship

Which of the following are probability samples? SELECT ALL THAT APPLY Cluster Sample Stratified random sample Quota sample Convenience sample Systematic sample

Systematic sample cluster sample stratified random sample

Match the following variables to the correct level of measurement (A. Interval, B. Nominal, C. Ratio, D. Ordinal) Temperature in Fahrenheit Presence or Absence of disease Weight in ounces Race Quality of life (1-5) Hemoglobin A1C Time in Minutes Level of education Oxygen Saturation Blood type

Temperature in Fahrenheit- A. Interval Presence or Absence of disease- B. Nominal Weight in ounces- C. Ration Race- B. Nominal Quality of life (1-5)- D. Ordinal Hemoglobin A1C- C. Ratio Time in Minutes- C. Ratio Level of education- D. Ordinal Oxygen Saturation- C. Ratio Blood type- B. Nominal

When reporting the mean for a variable, what measure of spread should be reported?

The standard deviation

A nurse researcher compares two interventions for preventing CAUTI in an academic medical center. A statistical test comparing the number of infections in the two groups yields a p-value of 0.10. This p-value means that. A. There is a statistically significant difference between the two groups. B.A larger sample is needed to to determine statistical significance C. The difference is clinically but not statistically significant D. There is not a statistically significant difference between the groups

There is not a statistically significant difference between the groups

All studies need appropriate permission to examine data

True

Pearson correlation coefficient can be positive or negative

True

Sample size influences the ability of a hypothesis test to detect statistically significant differences

True

The mean is the arithmetic average of the observations

True

The null hypothesis always stats that there is no relationship between the variables or differences between the groups

True