De Leon‐Ortega 2007.

Study characteristics
Patient Sampling	Data were obtained from the University of Alabama at Birmingham Optic Nerve Imaging Center database, which consists of functional and imaging data from glaucoma patients and controls enrolled in clinical studies from January 2000 to December 2004. Glaucoma patients were recruited by chart review and referrals, while controls were university employees, or were recruited from the general population. One eye per person was randomly selected.
Patient characteristics and setting	Sample size: 374 participants were initially enrolled, 78 glaucoma (44 African‐American, 34 European), 89 healthy controls (51 African‐American, 38 European) actually included in the analysis. Age: glaucoma African‐American patients mean ± SD, 49.5 ± 9.8 years, glaucoma European ancestry 49.4 ± 17.2 years, controls African‐American 47.3 ± 9.5 years, controls European ancestry 47.5 ± 8.8 years. Ethnicity: African‐American and European ancestry. Country: USA. Ocular comorbidities: no history of intraocular surgery (except uncomplicated cataract surgery), cataracts, problems affecting colour vision other than glaucoma, use of medication or any comorbid condition affecting visual function. BCVA ≥ 20/40, spherical refraction within ±5 D, and cylinder correction within ± 3D. Setting: University of Alabama at Birmingham. Spectrum of glaucoma severity: mean ± SD MD and PSD on the VF test were ‐3.6 ± 3.6 dB and 4.3 ± 3.1 dB, for glaucoma African‐American; ‐3.3 ± 3.2 dB and 4.1 ± 3.1 dB, for glaucoma European ancestry, respectively. Control participants: IOP < 22 mmHg, no past history of increased IOP, no family history of glaucoma, normal VF test results, and normal optic nerve appearance.
Index tests	Confocal scanning laser ophthalmoscopy: Heidelberg Retina Tomography (Heidelberg Engineering, Heidelberg, Germany). An experienced operator evaluated the image quality and outlined the disc margin, masked to the patient diagnosis. After obtaining the HRT 2 results, all scans with their respective contour lines were exported to a personal computer with the HRT 3 software. Images were excluded if they had: acquisition sensitivity > 89%, SD > 39, results, ONH not centred, excessive eye movement occurred during the acquisition movie, floaters over or adjacent to the disc. One author was a consultant for Carl Zeiss Meditec.
Target condition and reference standard(s)	Manifest glaucoma: glaucomatous VF result, defined as either GHT outside the 99% normal limits or a PSD outside the 95% normal limits, and at least 1 cluster of 3+ test points outside 95% confidence interval in the pattern deviation probability plot, without crossing the horizontal hemifield. Visual field testing: Humphrey Field Analyzer II, SITA standard, 24‐2 programme (Carl Zeiss Meditec, Inc., Dublin, CA, USA). VF reliability criteria included a fixation loss, false‐positive and false‐negative rates < 33%. Optic disc evaluation: dilated fundus examination, simultaneous stereoscopic optic disc photography.
Flow and timing	Of 374 patients initially enrolled, 167 were actually included in the analysis. 31 (> 10%) were excluded due to poor image quality, 5 patients were excluded due to poor quality in the stereophotograph.
Comparative
Notes	None.
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Unclear
Was a case‐control design avoided?	No
Did the study avoid inappropriate exclusions?	Yes
Could the selection of patients have introduced bias?		High risk
Are there concerns that the included patients and setting do not match the review question?			High
DOMAIN 2: Index Test (All tests)
If a threshold was used, was it pre‐specified?	Yes
Were imaging test's quality assessed?	Yes
Were any conflict of interest avoided	Yes
Could the conduct or interpretation of the index test have introduced bias?		Low risk
Are there concerns that the index test, its conduct, or interpretation differ from the review question?			Low concern
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?	Unclear
Could the reference standard, its conduct, or its interpretation have introduced bias?		Low risk
Are there concerns that the target condition as defined by the reference standard does not match the question?			Low concern
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	No
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	No
Did all patients receive a reference standard	Yes
Could the patient flow have introduced bias?		High risk