Relative, absolute and attributable measures of obesity and endometrial cancer are each read for their license in this PU570 Unit 2 exercise example, built on one composite cohort. Searches like "pu 570 unit 2 assignment example", "pu570 unit 2 sample" and "pu570 unit 2 example" land here.
What a finished PU570 Unit 2 measure interpretation exercise looks like
Five short parts, each answering one supplied question, make up the exercise across about four pages. The results table leads: 115 cancers among 6,400 women with a body mass index of 30 or more, 67 among 9,600 women between 18.5 and 24.9. Part A reads the crude risk ratio, 2.57, and the adjusted hazard ratio of 2.4 supplied by the investigators. Part B converts the same data into an absolute difference, 11 extra cases per 1,000 women over twelve years. Part C computes the fraction of cases among exposed women attributable to obesity, 58 percent, and Part D the population attributable fraction, 37 percent, using the share of cases who were exposed. Part E answers the question a reader actually asks: what the ratio means for one woman with obesity.
How a PU570 Unit 2 example is structured
Each part pairs a number with the claim it licenses and the claim it does not, and that pairing is the exercise's design. Relative measures lead because the supplied question starts there, but the example immediately notes that a ratio above 2 on a rare outcome describes a modest absolute change. One paragraph sets the hazard ratio apart from the crude risk ratio: it comes from a model that accounts for follow-up time and for age, parity and hormone use, so it is the figure to quote when causal interpretation is at stake. The attributable fractions come next and carry an explicit condition, since both assume the association is causal and would vanish if it were not. The individual-level question comes last, where the answer declines to turn a population ratio into a personal forecast.
Two ratios, one preferred
The crude 2.57 and the adjusted 2.4 are set side by side. The example explains why the adjusted hazard ratio is quoted in any sentence implying cause, and why the crude figure still describes the observed burden.
Eleven per thousand
The risk difference, 1.1 percentage points over twelve years, restated as 11 additional diagnoses per 1,000 women with obesity. Its reciprocal, about 91, appears with a caution about treating it as a number needed to harm.
Share among exposed women
Fifty-eight percent of cases among women with obesity would not have occurred without it, if the association is causal. The condition is written into the sentence, not left to a footnote.
Share of all cases
Thirty-seven percent of the cohort's endometrial cancers, computed from the proportion of cases who were exposed, a formula that remains valid with an adjusted ratio.
One woman, one ratio
A ratio of 2.4 does not tell a patient her own twelve-year risk; the cohort's absolute risk of 1.8 percent comes closer, and even that averages over women who differ in many ways.
Where marks go in PU570 Unit 2
Interpretation exercises in PU570 generally reward correct computation, correct reading and the restraint to stop where a measure stops. Computation marks are the smaller share. Reading marks depend on matching each figure to its question: a ratio for strength of association, a difference for public health burden, an attributable fraction for how much could in principle be prevented. The restraint row is where graduate papers separate. A population attributable fraction presented without its causal condition, or a hazard ratio read as a woman's personal chance of cancer, typically costs the row. Deductions also cluster around relative and absolute measures conflated, so that a ratio of 2.4 is written as a 2.4 percent risk, the crude figure quoted where the adjusted one belonged, and Levin's formula applied to an adjusted ratio without comment.
Get a PU570 Unit 2 example written to your instructions
Upload the results table and the questions from the PU570 Unit 2 exercise, along with the grading criteria. Every measure is computed or read in the order asked, each paired with what it licenses and what it cannot support. Turnaround is 24-48 hours, and that first custom sample carries no charge.
PU570 Unit 2 questions, answered
Why does the example prefer the adjusted hazard ratio?
Because any sentence implying that obesity contributes to endometrial cancer needs the estimate that accounts for the obvious alternative explanations. The adjusted 2.4 has done that for age, parity and hormone use; the crude 2.57 has not. Both belong in the exercise, since the crude figure describes what was observed, but only one should carry causal language.
What is the difference between the two attributable fractions?
The fraction among the exposed asks how many cases in women with obesity are due to obesity, here 58 percent. The population fraction asks how many cases in everyone are due to it, here 37 percent, which depends on how common obesity is. Both assume causation, and both describe populations, not a single woman's diagnosis.
Can the number needed to harm be quoted here?
With caution. The reciprocal of the risk difference, about 91, says that for every 91 women with obesity followed twelve years, one additional diagnosis would occur if the association is causal and the crude difference is unconfounded. Since the adjusted estimate is smaller, the example labels 91 as a rough illustration and does not build recommendations on it.