Table 5. Factors related to skin auto-fluorescence (in arbitrary units) using multivariate analyses stratified gender.

Risk Factor	Effect size (CI)	P-value	Effect size (CI)	P-value
	Males, n = 175		Females, n = 173
Age (years)	0.023 (0.016, 0.033)	< 0.001	0.019 (0.012, 0.027)	< 0.001
Ethnicity (South Asians = reference)
Arabs	0.15 (-0.04, 0.33)	0.11	0.30 (0.51, 0.55)	0.02
Filipinos	0.35 (0.02, 0.68)	0.04	0.33 (0.21, 0.65)	0.04
Smoking (non-smoking = reference)	0.21 (0.00, 0.41)	0.05	0.32 (-0.18, 0.81)	0.21
Diabetes (non-diabetic = reference)	0.13 (-0.04, 0.30)	0.13	0.16 (-0.04, 0.35)	0.11
Reflectance (%)	3.42 (0.57, 6.27)	0.02	0.15 (-1.59, 1.89)	0.86

Arab: Bahrain, Egypt, Iraq, Jordan, Kuwait, Lebanon, Morocco, Oman, Palestine, Qatar, Saudi Arabia, Somalia, Sudan, Syria, Tunisia, United Arab Emirates and Yemen. South Asian: India, Bangladesh, Nepal, Pakistan, Sri Lanka. Values represent regression coefficients (95% confidence interval) and their corresponding p-values. For categorical or dichotomous variables, the effect estimates represent the difference in skin AF compared with the reference group.