Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

[EX Q]: Context: Patients with chronic heart failure (CHF) have multiple abnormalities of autonomic regulation that have been associated to their high mortality rate. Heart rate recovery immediately after exercise is an index of parasympathetic activity, but its prognostic role in CHF patients has not been determined yet.', 'Ninety-two stable CHF patients (83M/9F, mean age: 51+/-12 years) performed an incremental symptom-limited cardiopulmonary exercise testing. Measurements included peak O2 uptake (VO2p), ventilatory response to exercise (VE/VCO2 slope), the first-degree slope of VO2 for the 1st minute of recovery (VO2/t-slope), heart rate recovery [(HRR1, bpm): HR difference from peak to 1 min after exercise] and chronotropic response to exercise [%chronotropic reserve (CR, %)=(peak HR-resting HR/220-age-resting HR)x100]. Left ventricular ejection fraction (LVEF, %) was also measured by radionuclide ventriculography.', 'Fatal events occurred in 24 patients (26%) during 21+/-6 months of follow-up. HRR1 was lower in non-survivors (11.4+/-6.4 vs. 20.4+/-8.1; p<0.001). All cause-mortality rate was 65% in patients with HRR1<or=12 bpm versus 11% in patients with HRR1>12 bpm (log-rank: 32.6; p<0.001). By multivariate survival analysis, HRR1 resulted as an independent predictor of mortality (chi2=19.2; odds ratio: 0.87; p<0.001) after adjustment for LVEF, VO2p, VE/VCO2 slope, CR and VO2/t-slope. In a subgroup of patients with intermediate exercise capacity (VO2p: 10-18, ml/kg/min), HRR1 was a strong predictor of mortality (chi2: 14.3; odds ratio: 0.8; p<0.001).
Answer: Early heart rate recovery is an independent prognostic risk indicator in CHF patients and could be used in CHF risk stratification.
[EX A]: Does early heart rate recovery after exercise predict mortality in patients with chronic heart failure?

[EX Q]: Context: No previous studies have investigated the psychiatric characteristics of patients with postherpetic neuralgia (PHN). Similarly, no studies have been performed on patients with different chronic somatic symptoms due to a defined medical disease to compare the characteristics of psychiatric morbidity associated with each etiology.', 'After completing the subscales of the Symptom Checklist 90-R, a psychiatrist administered the Diagnostic Interview Schedule to all subjects. The psychiatric comorbidity in 35 patients with pain due to PHN was compared with a control group of 34 patients with the nonpainful aversive symptom of vertigo due to a peripheral vestibular disorder that caused unilateral hypofunction.', 'PHN patients had significantly more symptoms of major depression and somatization disorder. No significant differences were found between groups for psychiatric diagnoses. Patients with PHN reported significantly less acutely distressing somatic symptoms.
Answer: These results suggest that the psychiatric symptoms of patients with PHN are distinct from nonspecific acute distress and may be related to the experience of suffering from chronic neuropathic pain. Patients with PHN may not meet criteria for a psychiatric diagnosis, but their psychiatric comorbidity places them at substantial risk for increased pain, suicidal ideation, sustained disability, and the numerous complications of excessive medical evaluation and treatment. Patients with PHN should be evaluated specifically for psychiatric symptoms to reduce potential negative consequences through appropriate treatment.
[EX A]: Do psychiatric symptoms and distress differ between patients with postherpetic neuralgia and peripheral vestibular disease?

[EX Q]: Context: To evaluate various formats for the communication of prenatal test results.', 'In study 1 (N=400), female students completed a questionnaire assessing risk perception, affect, and perceived usefulness of prenatal test results. A randomized, 2 (risk level; low, high) x 4 (format; ratio with numerator 1, ratio with denominator 1000, Paling Perspective Scale, pictograms) design was used. Study 2 (N=200) employed a 2 (risk level; low, high) x 2 (format; Paling Perspective Scale, risk comparisons in numerical format) design.', 'In study 1, the Paling Perspective Scale resulted in a higher level of perceived risk across different risk levels compared with the other formats. Furthermore, participants in the low-risk group perceived the test results as less risky compared with participants in the high-risk group (P < 0.001) when the Paling Perspective Scale was used. No significant differences between low and high risks were observed for the other 3 formats. In study 2, the Paling Perspective Scale evoked higher levels of perceived risks relative to the numerical presentation of risk comparisons. For both formats, we found that participants confronted with a high risk perceived test results as more risky compared with participants confronted with a low risk.
Answer: The Paling Perspective Scale resulted in a higher level of perceived risk compared with the other formats. This effect must be taken into account when choosing a graphical or numerical format for risk communication.
[EX A]:
Does the effect of graphical and numerical presentation of hypothetical prenatal diagnosis result on risk perception?