Hatok 2011.

Study characteristics
Patient sampling	Primary objective: to prospectively evaluate whether detection of CYP19 mRNA in eutopic endometrium could be used as specific screening tool for endometriosis as well as reflect its severity Participants: women with regular menstrual period undergoing laparoscopic surgery for pelvic pain Selection criteria: exclusion criteria: irregular menstrual cycle, secretory phase, menopause, history of hormonal treatment before surgery, previous abdominal surgery, pregnancy, history of IVF prior to laparoscopy Study design: observational single‐gate, prospective recruitment and sample collection
Patient characteristics and setting	Clinical presentation: pelvic pain Age: mean age 43.02 ± 6.8 years (range 25‐55) Number enrolled: 105 women Number available for analysis: 101 women (all in early proliferative phase) Setting: University hospital ‐ Jessenius Faculty of Medicine, Comenius University Place of study: Bratislava, Slovak Republic Period of study: not provided Language: English
Index tests	Index test: Aromatase P450 (CYP19) mRNA expression Description of positive case definition by index test as reported: "[i]ncreased aromatase mRNA expression" ‐ not specified (detection by RT‐PCR; analysis by gel electrophoresis with GeneTools software; quantified by relative quantification: expression of target relative to housekeeping gene (β‐actin); laboratory technique described; diagnostic threshold not provided Examiners: no information provided Interobserver variability: not provided
Target condition and reference standard(s)	Target condition: endometriosis Prevalence of target condition in the sample: n/N = 30/101 (30%): stage I‐II 15, stage III‐IV 15; adenomyosis ‐ 25, healthy controls ‐ 46, total non‐endometriosis controls 71 Reference standard: laparoscopy + histology Description of positive case definition by reference test as reported: surgical inspection confirmed by histological examination; rAFS classification Examiners: no information provided
Flow and timing	Time interval between index test and reference standard: tissue samples were obtained at surgery Withdrawals: 4 participants were excluded for low sample quality
Comparative
Notes	Conclusion: Significantly increased level of CYP19 mRNA was detected in patients, and this expression was significantly dependent on disease severity. These findings provide direct evidence that screening for endometrial aromatase could be beneficial in the prediction of oestrogen dependent disease. Comment: For the purpose of this review diagnostic estimates were calculated for endometriosis versus non‐endometriosis (controls included women with adenomyosis)
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Unclear
Did the study avoid inappropriate exclusions?	Yes
Was a 'two‐gate' design avoided?	Yes
		Unclear	Low
DOMAIN 2: Index Test All tests
Were the index test results interpreted without knowledge of the results of the reference standard?	Unclear
If a threshold was used, was it pre‐specified?	No
Was a menstrual cycle phase considered in interpreting the index test	Yes
		High	Low
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	Yes
Were the reference standard results interpreted without knowledge of the results of the index tests?	Yes
		Low	Low
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	Yes
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	Yes
		Low