Jeoung 2013.

Study characteristics
Patient Sampling	Healthy controls and glaucoma patients were among participants in the Macular Ganglion Cell Imaging Study, an ongoing prospective study of glaucoma patients and healthy individuals at the Glaucoma Clinic of Seoul National University Hospital. One eye per person was randomly selected.
Patient characteristics and setting	Sample size: 545 eyes of 545 participants initially considered, 425 eyes eventually included in the analysis (306 glaucoma, 119 controls). 164 eyes with early glaucoma, 142 with moderate‐to‐advanced glaucoma. Age: early glaucoma eyes mean ± SD, 58.7 ± 10.2 years; moderate‐to‐advanced glaucoma eyes mean ± SD, 59.2 ± 13.1 years; controls 57.1 ± 12.3 years. Sex: 213 men (160 glaucoma, 53 controls) and 212 women ( 146 glaucoma, 66 controls). Ethnicity: not specified. Country: Korea. Setting: Glaucoma Clinic of Seoul National University Hospital. Ocular comorbidities: patients with BCVA < 20/40 in the study eye, refractive > ±6 D equivalent sphere and ±3 D astigmatism, retinal disease (diabetic retinopathy, macular degeneration, retinal detachment, epiretinal membrane) or non‐glaucomatous optic nerve diseases, treatment that might be toxic to the retina or optic nerve, laser therapy, or ocular surgery except non‐complicated cataract surgery were excluded. Spectrum of glaucoma severity: the mean ± SD MD and PSD on the VF test were ‐2.68 ± 1.76 dB and 5.47 ± 2.8 db, respectively for early glaucoma, ‐12.41 ± 5.92 dB and 12.20 ± 3.16 dB for moderate‐to‐severe glaucoma. Control participants: IOP ≤ 21 mmHg with no history of increased IOP, normal ONH appearance, no RNFL defect on red‐free fundus photography and normal VF result.
Index tests	Optical coherence tomography: Cirrus HD‐OCT (software version 6.0, Carl Zeiss Meditec, Dublin, CA, USA). The macular cube 200 x 200 and optic disc cube 200 x 200 scanning protocols were used. The authors stated no conflict of interest.
Target condition and reference standard(s)	Manifest Glaucoma: glaucomatous optic disc cupping (defined as neuroretinal rim thinning, notching, excavation, or RNFL defect) and corresponding VF defect (defined as the presence of a cluster of 3+ non‐edge points on the pattern deviation plot with a P < 5%, with 1 of these points having a P < 1%, a PSD with P < 5% or a GHT outside normal limits). Visual field testing: Humphrey Field Analyzer (model II 750, 30‐2 SITA standard programme, Carl Zeiss Meditec, Inc, Dublin, CA, USA). Reliability criteria were fixation losses < 20, false‐positive and false‐negative rates < 33%. Optic disc and RNFL evaluation: colour disc photography, red‐free RNFL photography (TRC‐50IX; Topcon Corporation, Tokyo, Japan), evaluated independently by 2 observers in a random order and masked fashion, without knowledge of the clinical information.
Flow and timing	Index test and reference standard were performed within 1 month. 92 eyes were excluded because of diabetic retinopathy (n = 36), macular degeneration (n = 28), epiretinal membrane (n = 20), and ocular surgery history (n = 8). 28 eyes were excluded from the analysis due to poor‐quality images.
Comparative
Notes	Supported by Grant No. A121615 from the Korea Health technology R&D Project, Ministry of Health & Welfare, Republic of Korea, and by Grant No. 2009‐0091931 from the National Research Foundation of Korea (NRF) funded by the Korea government (MEST).
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?	Yes
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?	Yes
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