Characteristics of keratoconic patients at two main eye centres in Palestine: a cross-sectional study

BMC Ophthalmology

Table 2 Demographic characteristics of the study population in relation to sex

	Total n = 505 (%)	Male n = 250 (%)	Female n = 255 (%)	P value^a
Variable
Mean age (year) ± SD	23.33 ± 7.37	22.98 ± 7.53	23.37 ± 7.15	0.548^e
Age at presentation (year)^b
< 20	151(29.9)	79(31.6)	72 (28.2)	0.408^f
≥20	345 (70.1)	171(68.4)	183(71.8)	0.408^f
Bilateralism
Yes	443(88.2)	221 (88.4)	222(88.1)	0.916^f
No	62 (11.8)	29 (11.6)	33(11.9)	0.916^f
Severity of KC at presentation^c
Severe (k > 54)	93 (9.9)	42(9.2)	51(10.7)	0.030^f
Moderate (k = 48–54)	263 (28.1)	114(24.3)	149 (31.2)
Mild (k < 48 D)	580 (62)	303 (66)	277 (58.1)
BCVA^{c, d}
≤6/60	21(2.4)	12 (2.6)	9 (1.9)	0.975^f
> 6/60 to < 6/12	155 (16.5)	73(15.9)	82 (17.3)
≥6/12	670(71.5)	331(72.1)	339(71.1)

Abbreviations: SD standard deviation, KC Keratoconus, BCVA best-corrected visual acuity
^aThe P-value is bold where it is less than the significance level cut-off of 0.05
^b20 years is used as the cut-off point as in most of the studies [12]
^cValues of non-diseased eyes were not entered
^dMissing data for 90 patients
^eStatistical significance of differences calculated using the independent-samples t-test
^fStatistical significance of differences calculated using the Pearson’s chi-squared test

ISSN: 1471-2415