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.

The 6-min walk test (6MWT) has prognostic value in various pulmonary disorders including idiopathic pulmonary fibrosis (IPF). We determined the individual prognostic accuracy of distance walked and oxygen saturation during the 6MWT in patients with IPF. We defined a new composite index, the distance-saturation product (DSP), which is the product of distance walked and lowest oxygen saturation during the 6-min walk test. We compared the performance of the DSP to the individual 6MWT parameters in predicting mortality.', 'We evaluated pulmonary function tests, 6-min walk parameters and the DSP between survivors and non-survivors. The ability of each measure to discriminate outcomes was determined by receiver operator curves.', '81 patients (48 survivors, 33 non-survivors) were included. Pulmonary function tests were similar and did not correlate with survival. Desaturation was greater (89.4% versus 83.7%, P<0.001) and distance walked was lower (406.9 versus 181.3m, P = 0.005) in non-survivors. The DSP was significantly lower among non-survivors (364.8 versus 153.5m%, P < 0.001) and predicted mortality more accurately than either individual 6MWT component (P = 0.035 versus desaturation, P=0.040 versus distance). A DSP <200 m% was associated with a seven-fold greater risk of 12-month mortality and an 18.0% shorter median survival compared with a DSP > 200 m% (P < 0.001).
Does the distance-saturation product predict mortality in idiopathic pulmonary fibrosis?

The apolipoprotein B (apoB)/apoA-I ratio represents the balance of proatherogenic and antiatherogenic lipoproteins. The purpose of this study was to determine whether the apoB/apoA-I ratio was superior to any of the cholesterol ratios - total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C), low-density lipoprotein cholesterol (LDL-C)/HDL-C and non-HDL-C/HDL-C - in predicting the risk of coronary disease. Moreover, we examined whether any lipids, lipoproteins or cholesterol ratios add significant predictive information beyond that provided by the apoB/apoA-I ratio.', 'Plasma lipids, lipoproteins, apoB, and apoA-I were measured in 69,030 men and 57,168 women above 40 years of age. After a mean follow-up of 98 months, 1183 men and 560 women had died from a myocardial infarction in this prospective apolipoprotein-related mortality risk (AMORIS) study.', 'High apoB and a high apoB/apoA-I ratio were strongly related to increased coronary risk, while high apoA-I was inversely related to risk. The apoB/apoA-I ratio was superior to any of the cholesterol ratios in predicting risk. This advantage was most pronounced in subjects with LDL-C levels <3.6 mmol/l. Addition of lipids, lipoproteins or any cholesterol ratio to apoB/apoA-I in risk models did not further improve the strong predictive value of apoB/apoA-I.
Is the apoB/apoA-I ratio better than the cholesterol ratios to estimate the balance between plasma proatherogenic and antiatherogenic lipoproteins and to predict coronary risk?

To investigate the influence of clinical characteristics including nutritional markers on postoperative survival in patients undergoing total gastrectomy (TG) for gastric cancer (GC).', 'One hundred fifty-four patients were enrolled. Uni- and multivariate analyses using the Cox proportional hazard model were performed to explore the most valuable clinical characteristic that was associated with postoperative survival.', 'Multivariate analysis using twelve clinical characteristics selected from univariate analyses revealed that age ( 72/>72), carcinoembryonic antigen ( 20/>20) (ng/ml), white blood cell count ( 9.5/>9.5) ( 10(3)/mm(3)), prognostic nutritional index (PNI) ( 45/>45) and lymph node metastasis (negative/positive) were associated with postoperative survival. Kaplan-Meier analysis and log-rank test showed that patients with higher PNI (>45) had a higher postoperative survival rate than those with lower PNI ( 45) (p<0.001).
Is prognostic nutritional index associated with survival after total gastrectomy for patients with gastric cancer?