Gilabert‐Estelles 2007.

Study characteristics
Patient sampling	Primary objective: to analyse mRNA expression and protein levels of VEGF, PlGF and TSP‐1 in endometrium and peritoneal fluid of women with and without endometriosis and in ovarian endometrioma patients Participants: women of reproductive age undergoing laparoscopy for various indications Selection criteria: exclusion criteria: menstrual phase, irregular menstruation, pregnancy or breastfeeding in the previous 6/12 months, hormonal treatment for 3/12 months before surgery Study design: observational two‐gate, prospective sample collection
Patient characteristics and setting	Clinical presentation: indications for surgery ‐ clinical or sonographic suspicion of endometriosis (endometriosis group) and pelvic pain (12%), sterility (18%) or tubal sterilisation (70%) in controls Age: mean age: 32.7 years (range 19–46), endometriosis; 36.5 years (range 20–52 years), controls Number enrolled: 121 women (56 in proliferative and 65 in secretory cycle phase) Number available for analysis: 90 women Setting: University hospital ‐ Hospital Universitario La Fe Place of study: Valencia, Spain Period of study: not provided Language: English
Index tests	Index test: VEGF, PlGF, TSP‐1, uPA, PAI‐1, MMP‐3, TIMP‐1 Description of positive case definition by index test as reported: mRNA expression by RT‐PCR (analysis in a LightCycler apparatus v 3.5 (Roche Molecular Biochemicals, Germany), normalised to b‐actin); antigen protein levels of VEGF, PIGF, uPA, PAI‐1, MMP‐3 and TIMP‐1 by commercially available ELISAs and TSP‐1 ‐ by indirect ELISA; laboratory technique and sample handling described Examiners: no information provided; unclear if blinded to the result of reference standard Interobserver variability: CV for TSP‐1 protein assay was 4.8%, not reported for other tests
Target condition and reference standard(s)	Target condition: endometriosis Prevalence of target condition in the sample: n/N = 71/121 (59%): all stage III‐IV; controls 50 Reference standard: laparoscopy + histopathology Description of positive case definition by reference test as reported: visual inspection of abdominal cavity confirmed by histology; staging according to rASRM classification Examiners: no information provided
Flow and timing	Time interval between index test and reference standard: not specified, but from the context appears that the samples were obtained at surgery Withdrawals: 31 endometriosis patients were excluded due to insufficient sample quantity
Comparative
Notes	Conclusion: Endometrium and peritoneal fluid from women with endometriosis have increased levels of VEGF, uPA and MMP‐3. Therefore, the development of endometriotic implants at ectopic sites may be facilitated, promoting the progress of endometriosis Comments: For PIGF, TSP‐1 and PAI‐1, TIMP‐1 mRNA there was no statistically significant difference between the groups ‐ no data available for meta‐analysis (Appendix 7) For VEGF, uPA, MMP‐3 and TIMP‐1 protein there was statistically significant difference between the groups, but there were insufficient data to construct 2 × 2 tables; not included in this review
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	No
Did the study avoid inappropriate exclusions?	Yes
Was a 'two‐gate' design avoided?	No
		High	High
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?	Unclear
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	No
		High