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.

Example Input: Context: Completeness of cytoreduction is a significant predictor of long-term outcome after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Imaging has limited sensitivity to identify peritoneal metastases and therefore predict whether complete cytoreduction is possible. We reviewed our experience using laparoscopy to determine candidates for complete cytoreduction and HIPEC.', 'This single-center, retrospective study examined patients from 2007 to 2014 who underwent laparoscopy to determine complete cytoreduction (CC-0/1)/HIPEC candidacy. Preoperative, intraoperative, and postoperative data were collected.', 'A total of 145 laparoscopies were performed on 141 patients, 72 (51.1\xa0%) of whom were female, with a median age of 53\xa0years (range 20-79). The primary site was appendiceal in 67 (47.5\xa0%) patients, colorectal in 43 (30.5\xa0%), mesothelioma in 17 (12.1\xa0%), unknown in 9 (6.4\xa0%), small bowel in 3 (2.1\xa0%), gastric in 1, and ovarian in 1 (0.7\xa0% each). Overall, 115 (81.6\xa0%) patients had prior abdominal surgery, 111 (76.6\xa0%) had evidence of disease on imaging, and 117 (80.7\xa0%) underwent prior chemotherapy, with a median of 5.9\xa0weeks between the last treatment and laparoscopy (0.9-498.9\xa0weeks). Four (2.8\xa0%) intraoperative complications were observed (one liver laceration, two enterotomies, and one air embolus), and nine (6.2\xa0%) postoperative complications [four (2.8\xa0%) Clavien grade (CG) I, three (2.8\xa0%) CG II, one (0.7\xa0%) CG III (return to operating room) and one (0.7\xa0%) CG IV (transient ischemic attack)]. Forty-eight patients deemed candidates by laparoscopy underwent CRS/HIPEC (positive predictive value 82.8\xa0%).
Answer: Diagnostic laparoscopy is a safe, feasible, and accurate staging tool in patients with suspected peritoneal metastases being considered for CRS.
Example Output: Is laparoscopy Safe and Accurate to Evaluate Peritoneal Surface Metastasis Prior to Cytoreductive Surgery?

Example Input: Context: The clinical value of oesophageal histology in non-complicated gastro-oesophageal reflux disease (GORD) is controversial. Our aim was to explore the role of histology in preoperative diagnosis and postoperative follow-up in GORD.', 'From 40 patients 2 histopathologists graded and scored 191 oesophageal biopsies in a blinded manner to evaluate inter- and intraobserver variation pre- and postoperatively. Correlation between preoperative histology and objective clinical findings (endoscopy, esophageal 24-hour pH monitoring, and manometry) was calculated as well.', 'Pathologist I interpreted 16 (50%) preoperative biopsies as normal, 5 (16%) with mild, 4 (12.5%) moderate, and 7 (21.9%) severe reflux changes. Pathologist II interpreted 11 (35.5%) preoperative biopsies as normal, 11 (35.5%) with mild, 6 (19.4%) moderate, and 3 (9.7%) severe reflux changes. In preoperative biopsies, interobserver variation was 33.8% and intraobserver variation 9.7%. A positive correlation was detectable between preoperative endoscopic and morphologic findings; no correlation existed between either acid reflux or LES pressure and oesophageal morphology. Normal pH monitoring and fundic wrap were noted postoperatively in all cases. In postoperative histology no significant differences according to pathologist I existed when compared with preoperative changes: 22 normal (69%), 7 mild (22%), 1 moderate (3.1%), and 2 severe (6.3%). Compared to preoperative analysis, pathologist II interpreted 24 (77%, p = 0.001) of the postoperative findings as normal, 1 (3%, p = 0.003) as mild, 4 (12.9%, n.s.) as moderate, and 2 (6.5% n.s.) as severe reflux changes. In postoperative biopsies interobserver variation was 21.1% and intraobserver variation 5.6%.
Answer: The role of oesophageal histology in preoperative diagnosis and postoperative follow-up of GORD may be considered limited.
Example Output: Is oesophageal histology in gastro-oesophageal reflux disease of minor pre- and postoperative diagnostic value?

Example Input: Context: To determine the extent of genetic variation among internationally collected HIV-1 isolates, to analyse phylogenetic relationships and the geographic distribution of different variants.', 'Phylogenetic comparison of 70 HIV-1 isolates collected in 15 countries on four continents.', 'To sequence the complete gag genome of HIV-1 isolates, build multiple sequence alignments and construct phylogenetic trees using distance matrix methods and maximum parsimony algorithms.', 'Phylogenetic tree analysis identified seven distinct genotypes. The seven genotypes were evident by both distance matrix methods and maximum parsimony analysis, and were strongly supported by bootstrap resampling of the data. The intra-genotypic gag distances averaged 7%, whereas the inter-genotypic distances averaged 14%. The geographic distribution of variants was complex. Some genotypes have apparently migrated to several continents and many areas harbor a mixture of genotypes. Related variants may cluster in certain areas, particularly isolates from a single city collected over a short time.
Answer: The genetic variation among HIV-1 isolates is more extensive than previously appreciated. At least seven distinct HIV-1 genotypes can be identified. Diversification, migration and establishment of local, temporal 'blooms' of particular variants may all occur concomitantly.
Example Output:
Does phylogenetic analysis of gag genes from 70 international HIV-1 isolates provide evidence for multiple genotypes?