Table 2.

Clinical characteristics of the study subjects

		Groups
Parameters	Level	Total ( n = 612)	RP ( n = 264)	Stargardt ( n = 76)	Cone- Rod Dystrophy (n = 109)	Usher Syndrome ( n = 54)	Control ( n = 109)	P -value
BCVA (LogMAR)	Mean $\pm$ SD	1.04 $\pm$ 0.91	1.19 $\pm$ 0.98	1.02 $\pm$ 0.47	1.43 $\pm$ 0.87	0.84 $\pm$ 0.69	0 $\pm$ 0	$<$ 0.001
	Median (range)	0.8 (0 to 2.79)	0.8 (0 to 2.79)	0.9 (0.1 to 2.31)	1.31 (0 to 2.7)	0.74 (0.1 to 2.7)	0 (0 to 0)
SE (D)	Mean $\pm$ SD	–1.0 $\pm$ 1.78	–0.88 $\pm$ 1.79	–1.54 $\pm$ 1.33	–0.88 $\pm$ 2.07	–1.67 $\pm$ 1.94	–0.33 $\pm$ 0.94	$<$ 0.001
	Median (range)	–0.75 (–6.63 to 2.75)	–0.5 (–5.75 to 2.75)	–1.25 (–5.25 to 0.75)	–0.31 (–6.63 to 2.63)	–1.5 (–5.75 to 1.5)	–0.38 (–2 to 2)
CMT (µm)	Mean $\pm$ SD	215.99 $\pm$ 72.1	230.66 $\pm$ 68.81	165.54 $\pm$ 65.04	186.03 $\pm$ 48.59	244.88 $\pm$ 99.87	258.72 $\pm$ 15.71	$<$ 0.001
	Median (range)	213 (80 to 690)	222 (95 to 674)	141 (80 to 378)	186.5 (88 to 317)	229.5 (90 to 690)	259.5 (220 to 285)
Color Vision	Normal	164 (28.1%)	40 (16.1%)	6 (8.3%)	2 (1.9%)	7 (14.6%)	109 (100.0%)	$<$ 0.001
	CVD	213 (36.5%)	71 (28.6%)	53 (73.6%)	62 (57.9%)	27 (56.3%)	0 (0.0%)
	N/A	207 (35.4%)	137 (55.2%)	13 (18.1%)	43 (40.2%)	14 (29.2%)	0 (0.0%)
Cataract Type (%)	No	376 (62.0%)	101 (38.5%)	69 (95.8%)	80 (73.4%)	17 (31.5%)	109 (100.0%)
	CC	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	$<$ 0.001
	NS	44 (7.3%)	29 (11.1%)	0 (0.0%)	11 (10.1%)	4 (7.4%)	0 (0.0%)
	PSC	169 (27.9%)	120 (45.8%)	3 (4.2%)	16 (14.7%)	30 (55.6%)	0 (0.0%)
	PCIOL	14 (2.3%)	12 (4.6%)	0 (0.0%)	2 (1.8%)	0 (0.0%)	0 (0.0%)
	Posterior Polar	3 (0.5%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	3 (5.6%)	0 (0.0%)
Optic Atrophy (%)	No	46 (9.1%)	10 (3.8%)	22 (28.9%)	14 (12.8%)	0 (0.0%)	0 (0.0%)	$<$ 0.001
	Yes	457 (90.9%)	254 (96.2%)	54 (71.1%)	95 (87.2%)	54 (100.0%)	0 (0.0%)
Macular Involvement (%)	No	122 (19.9%)	11 (4.2%)	0 (0.0%)	2 (1.8%)	0 (0.0%)	109 (100.0%)	$<$ 0.001
	Yes	490 (80.1%)	253 (95.8%)	76 (100.0%)	107 (98.2%)	54 (100.0%)	0 (0.0%)
RP, retinitis pigmentosa; BCVA, best corrected visual acuity; LogMAR, logarithm minimum angle of resolution; SE, spherical equivalent; D, diopter; CMT, central macular thickness; µm, micrometer; CVD, color vision defect; N/A, not applicable; CC, cortical cataract; NS, nuclear sclerotic; PSC, posterior subcapsular; SD, standard deviation; n, number *These parameters are presented based on monocular findings