Given a passage, 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.

Example Input: Pathologic change in Alzheimer disease (AD) begins some years before symptoms. MRS has the potential to detect metabolic abnormalities reflecting this early pathologic change. Presenilin 1 (PS1) and amyloid precursor protein (APP) mutation carriers have a nearly 100% risk of developing AD and may be studied prior to symptom onset.', 'Short echo time proton MR spectra were acquired from a midline posterior cingulate voxel in presymptomatic carriers of PS1 or APP mutations ("presymptomatic mutation carriers" [PMCs]; n = 7) and age- and sex-matched control subjects (n = 6). Ratios of N-acetyl aspartate (NAA), myo-inositol (MI), and choline-containing compounds (Cho) to creatine (Cr) were measured and NAA/MI calculated. Regression analyses and t tests were performed after log transformation.', 'PMC and control subjects were matched for age and sex. PMC subjects were 1.7 to 21.6 years (mean 9.8 years) before expected symptom onset, predicted from family-specific mean age at onset. Age did not significantly affect metabolite ratios. Geometric mean ratios in control subjects were as follows: NAA/Cr = 1.75, MI/Cr = 0.59, and NAA/MI = 2.95. NAA/Cr and NAA/MI were significantly reduced in PMC relative to controls (NAA/Cr mean decrease 10% [95% CI 2 to 18%]; NAA/MI mean decrease 25% [95% CI 3 to 44%]). MI/Cr was increased in PMC, but the differences did not achieve significance (19% increase [95% CI 1% decrease to 41% increase]; p = 0.07)). In PMCs, reduction in NAA/MI (p = 0.001) and MI/Cr (p = 0.002) were related to proximity of expected age at onset.
Example Output: Does mRS show abnormalities before symptoms in familial Alzheimer disease?

Example Input: Immune monitoring (IM) has not been shown to be associated with cardiac allograft vasculopathy (CAV).', 'Maximal intimal area, average percent stenosis, plaque volume, and maximal intimal thickness (MIT) were measured for matched baseline and one-yr IVUS segments in a blinded fashion. Patients were divided into quartiles by IM scores and outcomes compared. Optimal IM cutoff was determined.', 'IM assays were measured at 63.7 ± 16.4 d after transplantation in fifty patients. Progression of maximal intimal area (p = 0.005), average percent stenosis (p < 0.001), plaque volume (p = 0.005), and MIT (p = 0.001) were increased across the quartiles. An optimal IM assay cutoff of 406.0 ng ATP/mL demonstrated a sensitivity of 66.7% and specificity of 94.3% for predicting rapid progression of MIT ≥ 0.5 mm. Mean IM scores for Group 1 vs. Group 2 were 176.4 ± 102.2 and 616.3 ± 239.5 ngATP/mL, respectively. Rapid progression of MIT ≥ 0.5 mm occurred in 5/38 patients (13.2%) in Group 1 vs. 10/12 patients (83.3%) in Group 2 (p < 0.001). The risk ratio for rapid progression with elevated IM was 11.7 (p < 0.001).
Example Output: Is elevated immune monitoring early after cardiac transplantation associated with increased plaque progression by intravascular ultrasound?

Example Input: To determine whether the number and location of positive surgical margins (PSMs) in radical prostatectomy (RP) surgical specimens affect biochemical recurrence (BCR) rates.', 'The locations of PSMs were recorded for 1308 consecutive men who underwent RP between October 2000 and December 2006. BCR was defined as three consecutive prostate-specific antigen (PSA) level rises with the peak level >or=0.15 ng/mL. Multivariate regression analyses were used to identify preoperative predictors of PSMs and BCR. The estimated 5-year risk of BCR was calculated using the Kaplan-Meier method.', 'In all, 128 (9.8%) men had one or more PSMs. The mean body mass index, mean preoperative serum PSA level, the distributions of clinical stage and biopsy Gleason scores, and the presence or absence of biopsy perineural invasion were significantly different between men with or with no PSMs. In multivariate analysis, baseline serum PSA level, Gleason score and perineural invasion were independent preoperative predictors of PSMs. The 5-year actuarial BCR rates were dependent on the site of the PSM (P = 0.035) and not the number of PSMs (P = 0.18). The rank order of estimated 5-year BCR rates according to the site of PSMs were base > anterior > posterolateral > apex approximately posterior.
Example Output:
Does site of positive surgical margins influence biochemical recurrence after radical prostatectomy?