As part of a study, investigators wanted to assess the accuracy

1. As part of a study, investigators wanted to assess the accuracy of self-reported smoking status.  Participants are asked whether they currently smoke or not.  In addition, laboratory tests are performed on hair samples to determine presence or absence of nicotine.  The laboratory assessment is considered the gold standard, or truth about nicotine.  The data are as follows:

 Nicotine Absent Nicotine Present Self-Reported Non-Smoker 82 14 Self-Reported Smoker 12 52

A.    What is the sensitivity of self-reported smoking status?

B.     What is the specificity of self-reported smoking status?

2. A recent study reported that the prevalence of hyperlipidemia (defined as total cholesterol over 200) is 30% in children 2–6 years of age.  If 12 children are analyzed,

A.    What is the probability that at least 3 are hyperlipidemic?

B.     What is the probability that 3 are hyperlipidemic?

C.     How many would be expected to meet the criteria for hyperlipidemia?

Refer to the Histogram tab in the Excel Assignment Spreadsheet and answer the following.

What percent of the sample weighs 170 lbs. or less? ____

How many subjects weigh more than 200 lbs? ____ 1 pt

What percent of the subjects weigh more than 200 lbs? ____ % 1 pt

Based on the graph the median weight is approximately: _____ lbs. 1 pt

How many subjects weigh less than 200 lbs? _____ lbs. 1 pt

Refer to the PercentileRank tab in the Excel Assignment Spreadsheet to answer the following questions.

What percent of the sample weigh 172 lbs. or less? ______ % 1 pt

What percent of the sample is 200 lbs or more? ______ 1 pt

What is the median weight? _____ lbs. 1 pt

25% of the sample weighs less than or equal to: _____ lbs. 1pt

Look at the summary statistics in the Descriptives tab.

What is the median for Wt Grp 3? _194_____ 1 pt