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: The Cochrane Central Register of Controlled Trials, PubMed Medline and Latin American and Caribbean Health Science literature databases were searched, and searches made by hand of identified papers, to source relevant data. (BIOSIS Previews) were searched. There were no language restrictions.', 'Studies were evaluated by two reviewers independently. Only clinical trials were included that were published in the English, Spanish and Portuguese languages and were performed on humans. Articles were excluded when the examiners were not calibrated; when they did not compare manual and electronic probing techniques; when they did not measure the clinical attachment level (CAL); and when the subjects did not present destructive periodontal disease or had already received periodontal treatment.', 'The quality of the identified studies was assessed and standardised data extracted. Only two studies met all the selection criteria so no meta-analysis was performed.', 'Only two of the 37 identified articles were included in the review. The results of these two studies showed that the mean variance and the absolute mean difference between CAL measurements for the two types of probes were not statistically different.
Example Output: Do manual and electronic probes have similar reliability in the measurement of untreated periodontitis?

Example Input: In the most recent version of the UICC TNM classification system for thyroid carcinoma, tumors with minimal extrathyroid extension were classified as T3. In this study, we investigated whether this upgrading is appropriate for papillary thyroid carcinoma.', 'We investigated the difference in the relapse-free survival (RFS) rate between patients with tumors having no, minimal, and massive extrathyroid extension in a series of 502 patients over the age of 45 years.', 'Patients with tumors showing massive extension showed a worse RFS rate except for those with tumors measuring 1 cm or less. However, there was no significant difference in RFS between tumors measuring 4 cm or less showing no or minimal extension. In an investigation of 409 patients without any clinically apparent node metastasis, the RFS of patients with tumors larger than 4 cm with massive extension was significantly worse than those with tumors measuring 4 cm or less, while the RFS of patients with tumors with either no or minimal extension did not depend on the tumor size.
Example Output: Does minimal extrathyroid extension affect the relapse-free survival of patients with papillary thyroid carcinoma measuring 4 cm or less over the age of 45 years?

Example Input: The interassay variability found in the measurement of testosterone (T) levels warrants the need for laboratories to validate their methods to establish trustworthy cut-off points for diagnosis of male hypogonadism. The aims of this study were to validate measurement of total T (TT) at our laboratory in order to obtain reference ranges for TT, calculated free T (CFT), calculated bioavailable T (CBT), and salivary T (ST) in healthy young men from the Mediterranean region, and to evaluate the potential clinical value of ST by establishing its correlation with serum T.', 'An observational, cross-sectional study with sequential sampling.', 'men aged 18-30 years with body mass index (BMI)<30.', "chronic diseases, hepatic insufficiency or use of drugs altering circulating T levels. Main outcome measures TT (chemiluminescent immunoassay UniCell DXI 800 [Access T Beckman Coulter]), CFT and CBT (Vermeulen's formula), and ST (radioimmunoassay for serum TT modified for saliva [Coat-A-Count, Siemens]). Descriptive statistical analyses and correlation by Spearman's rho (SPSS 19.0 Inc., Chicago) were used.", 'One hundred and twenty-one subjects aged 24±3.6 years with BMI 24±2.5 kg/m(2) were enrolled. Hormone study: TT, 19±5.5 nmol/L (reference range [rr.] 9.7-33.3); CFT, 0.38 nmol/L (rr. 0.22-0.79); CBT, 9.7 nmol/L (rr. 4.9-19.2); and ST, 0.35 nmol/L (rr. 0.19-0.68). Correlation between ST and CFT was 0.46.
Example Output:
Does reference range for serum and salivary testosterone in young men of Mediterranean region?