Table 2.

Characteristics of studies assessing diagnostic ability of β-PPA

Study	Numbers of POAG	Numbers of healthy controls	Index test	TP	FP	FN	TN
Jonas et al. [2, 24]	312	125	Clinical diagnosis	208	25	104	100
Budde and Jonas [21]	501	481	Clinical diagnosis	312	121	189	360
Emdadi et al. [20]	29	29	Clinical diagnosis	13	2	16	27
Sugiyama [18]	207	11,727	Glaucomatous optic neuropathy	164	3319	43	8408
Pan et al. [14]	45	42	Clinical diagnosis	22	8	23	34
Wu et al. [13]	27	32	Clinical diagnosis	21	7	6	25
Xu et al. [12]	93	3910	Clinical diagnosis	64	938	29	2972
Hayashi et al. [9]	100	100	Clinical diagnosis	84	63	16	36
Sullivan-Mee et al. [7]	63	48	Clinical diagnosis	48	18	15	30
Miki et al. [3]	50	43	Clinical diagnosis	47	18	3	25
Mataki et al. [5]	84	2129	Clinical diagnosis	65	1165	19	964
Skaat et al. [6]	801	1149	Glaucomatous optic neuropathy	618	716	183	433
Lee et al.[33]	88	88	Clinical diagnosis	88	55	0	33
Sayed et al.[35] (SD-OCT)	100	100	Clinical diagnosis	90	69	10	31

Clinical diagnosis means that ‘POAG’ & ‘healthy controls’ were diagnosed not only by morphology of the optic disc but also by other clinical symptoms, including visual field, IOP and thickness of optic nerve fibre layer. Glaucomatous optic neuropathy means that the researchers only studied the morphology of glaucomatous optic discs

Abbreviations: FN false negative, FP false positive, TN true negative, TP true positive

Sensitivity indicates that the TP rate is equivalent to TP/(TP + FN). Specificity indicates that the TN rate is equivalent to TN/(TN + FP)