Quiz 1 (Please download quiz and complete offline.

Quiz 1

(Please download quiz and complete offline. Once you have completed the quiz, input your answers into the Quiz Shell in the

Exam folder on the course page. For Essay questions it is best to type your answer in a word processing program and copy and

paste your response to the Quiz Shell.)

Chapter 1

Please read Article 1 (Attached to this quiz) and answer the following questions:

1. Is this study a descriptive or inferential? Explain your answer.

2. What research question was the author trying to answer?

3. Were the data obtained from a survey or an experiment? Explain your answer.

4. Are possible sources of bias mentioned? If so, what are they?

5. Are the conclusions mentioned in this article warranted? Explain your answer. Please read chapter 2 of your text (Basic Biostatistics)

and provide a brief but detailed answer to the following questions.

6. Why was such a large trial necessary?

7. Why was a control group needed?

8. Why was it important to include a double blind feature?

9. If volunteers had been used in this trial rather than a random sample of

individuals, of what value would the results have been? Chapter 2

10. Which of the following correctly describes the relationship between a sample and a population?

A) A population and a sample are not related.

B) A sample is a group of subjects selected from a population to be studied.

C) A sample is a group of populations that are subject to observation.

D) A population is a group of samples that may or may not be included in a study. 11. What is the most important factor in selecting an appropriate sample?

A) The size of the sample

B) The sample must be representative of the population

C) The method used to collect the sample

D) The time it take to get a good sample

12. Which of the following correctly describes the relationship between a sample and a population?

A) A population and a sample are not related.

B) A sample is a group of subjects selected from a population to be studied.

C) A sample is a group of populations that are subject to observation.

D) A population is a group of samples that may or may not be included in a study. There were 30 patients in the 3rd ward of Goodfellow General Hospital. These patients were undergoing various studies for sleeping deprivation. A sleep study specialist

recorded the average hours of REM sleep for the patients on the ward during a 2 day study. The sleep study specialist found that the average hours of REM sleep a patient got per day during the two day study was 6.2 hours with a standard deviation of 1.6 hours. Please respond True or False to the following statements (13-16).

13. The subjects studied represent a population.

14. The average number of hours of REM sleep is a parameter of the study.

15. The standard deviation is a statistic associated with the study.

16. The sampling method in this case was convenience sampling.

17. In what ways are a random sample, convenience sample, and a systematic sample

different? In what ways are they similar?

18. Discuss stratified sampling and cluster sampling and describe a situation where it would

be effective to use each method of sampling in a clinical trial. Chapter 3

Select the correct letter response.

19. A variable measuring the number of people in a group

a. Cannot be analyzed as either continuous or discrete

b. Could be analyzed as either continuous or discrete depending on the whether there

are a large or small number of people in the group

c. Can only be analyzed as a continuous variable

d. Can only be analyzed as a discrete variable

20. If you classified the fruit in a basket as apple, orange, or banana, this would be an example of which level of measurement?

a. ratio scale b. nominal scale c. ordinal scale d. interval scale

21. Respondents in a child care survey are asked to state the number and ages of children in

their household. The number of children is measured on the ____ scale of measurement.

a. ordinal scale b. ratio scale c. nominal scale d. interval scale

22. The scale of measurement that is used to assign study volunteers a number in order

to

study individual reaction to a certain drug is the:

a. ordinal scale b. ratio scale c. nominal scale d. interval scale

23. Data obtained from an ordinal scale a. must be numeric b. must be qualitative

c. must be alphabetic d. must be countable

24. Social security numbers consist of numeric values. Therefore, social security is an example of

a. a quantitative variable b. either a quantitative or a qualitative variable

c. a grouping variable d. a qualitative variable

25. Fifteen percent of respondents in a survey studying smoking habits of minors in an inner

city school district found were found to smoke more than a pack of cigarettes a day. Twenty percent of the minors smoked 15 – 20 cigarettes per day, while 35 % of minors smoked between 5 and 14 cigarettes per day. Thirty percent of the minors surveyed smoked less than 5 cigarettes a day. The graphical device(s) which can be used to present these data is (are)

a. a line graph b. only a bar graph

c. only a pie chart d. both a bar graph and a pie chart

26. A tabular summary of a set of data showing the fraction of the total number of items in

several classes is a

a. frequency distribution

b. relative frequency distribution

c. frequency

d. cumulative frequency distribution Chapter 4

27. Which measures of central tendency are not affected by extremely low or extremely

high values?

a. Mean and median

b. Mode and median

c. Mean and mode

d. Geometric mean and mean

28. What is the relationship among the mean, median and mode in a symmetric distribution?

a. Mean is always the largest value

b. Mean is always the smallest value

c. All equal

d. Mode is the largest value

e. None of the above

29. What is a disadvantage of the range as a measure of dispersion? a. Based on only two observations

b. Can be distorted by a large mean

c. Not in the same units as the original data d. Has no disadvantage

e. None of the above

30. What is the relationship between the variance and the standard deviation? a. Variance is the square of the standard deviation

b. Variance is the square root of the standard deviation

c. Variance is twice the standard deviation

d. No constant relationship between the variance and the standard deviation

e. None of the above

31. Mercy Hospital is in a neighborhood where the mean family income is $45,000 with a

standard deviation of $9,000. Midtown General Hospital (MGH) is in a neighborhood where the mean family income is $100,000 and the standard deviation is $30,000. What are the relative variations of the family incomes in the two neighborhoods where the hospitals are?

a. Mercy 20%, MGH 30%

b. Mercy 40%, MGH 20%

c. Mercy 30%, MGH 20%

d. Mercy 50%, MGH 33%

32. A numerical value used as a summary measure for a sample, such as sample mean, is

known as a

a. sample statistic b. sample parameter

c. population mean d. population parameter

33. Since the population size is always larger than the sample size, then the sample statistic

a. can be smaller, larger, or equal to the population parameter

b. can never be equal to the population parameter

c. can never be larger than the population parameter

d. can never be smaller than the population parameter

34. Which of the following symbols represents the size of the population?

a. N b. s c. d.

35.A hospital employee survey capturing the number of hours an employee spent daily workingout

side their prescribed duties showed a positively skewed distribution. What is the best method to understand the central tendency of this data?

a. mean b. median c. mode d. range

Article 1: Study links 45,000 U.S. deaths to lack of insurance

By Susan Heavey Susan Heavey –Fri Sep 18, 8:22 am ET

WASHINGTON (Reuters) – Nearly 45,000 people die in the United States each year -- one every 12 minutes -- in large part because they lack health insurance and can not get good care, Harvard Medical School researchers found in an analysis released on Thursday.

"We're losing more Americans every day because of inaction ... than drunk driving and homicide combined," Dr. David Himmelstein, a co-author of the study and an associate professor of medicine at Harvard, said in an interview with Reuters.

Overall, researchers said American adults age 64 and younger who lack health insurance have a 40 percent

higher risk of death than those who have coverage.

The findings come amid a fierce debate over Democrats' efforts to reform the nation's $2.5 trillion U.S. healthcare industry by expanding coverage and reducing healthcare costs.

President Barack Obama's has made the overhaul a top domestic policy priority, but his plan has been besieged by critics and slowed by intense political battles in Congress, with the insurance and healthcare industries fighting some parts of the plan.

The Harvard study, funded by a federal research grant, was published in the online edition of the American

Journal of Public Health. It was released by Physicians for a National Health Program, which favors government-backed or "single-payer" health insurance.

An similar study in 1993 found those without insurance had a 25 percent greater risk of death, according to

the Harvard group. The Institute of Medicine later used that data in its 2002 estimate showing about 18,000

people a year died because they lacked coverage.

Part of the increased risk now is due to the growing ranks of the uninsured, Himmelstein said. Roughly 46.3 million people in the United States lacked coverage in 2008, the U.S. Census Bureau reported last week, up from 45.7 million in 2007.

Another factor is that there are fewer places for the uninsured to get good care. Public hospitals and clinics

are shuttering or scaling back across the country in cities like New Orleans, Detroit and others, he said. Study co-author Dr. Steffie Woolhandler said the findings show that without proper care, uninsured people

are more likely to die from complications associated with preventable diseases such as diabetes and heart

disease.

Some critics called the study flawed.

The National Center for Policy Analysis, a Washington think tank that backs a free-market approach to health care, said researchers overstated the death risk and did not track how long subjects were uninsured.

Woolhandler said that while Physicians for a National Health Program supports government-backed coverage, the Harvard study's six researchers closely followed the methodology used in the 1993 study conducted by researchers in the federal government as well as the University of Rochester in New York. The Harvard researchers analyzed data on about 9,000 patients tracked by the U.S. Centers for Disease Control and Prevention's National Center for Health Statistics through the year 2000. They excluded older Americans because those aged 65 or older are covered by the U.S. Medicare insurance program.

"For any doctor ... it's completely a no-brainer that people who can't get health care are going to die more from the kinds of things that health care is supposed to prevent," said Woolhandler, a professor of medicine

at Harvard and a primary care physician in Cambridge, Massachusetts. (Editing by Xavier Briand)