Stages of syphilis in South China – a multilevel analysis of early diagnosis

BMC Public Health

Table 3 Comparison of history of exposure and characteristics of diagnosis situation between early diagnosis (n = 18,101) and delayed diagnosis (n = 65,843) in multivariable logistic regression and multilevel model, adjusted for age at diagnosis and gender (2014 to mid-2015, Guangdong Province)

	Total	Early diagnosis		Multivariable logistic regression	Multilevel model
		frequency	%	aOR (95% C.I.)^a	aOR (95% C.I.)^a
History of exposure
Extramarital sexual history					PCV: -27%
No	3860	776	20%	ref	ref
Yes	9037	2052	23%	1.05 (0.95–1.16)	1.03 (0.93–1.14)
Sex with regular partner who was tested positive for syphilis					PCV: -26%
No	9777	2298	24%	ref	ref
Yes	3120	530	17%	0.83 (0.74–0.93)*	0.84 (0.75–0.94)*
Sex with MSM^b					PCV: -15%
No	12498	2635	21%	ref	ref
Yes	399	193	48%	2.73 (2.23–3.35)*	3.06 (2.49–3.77)*
Reasons for testing
Test for those visiting STD clinic or VCT					PCV: 19%
No	18475	2755	15%	ref	ref
Yes	6732	2023	30%	1.97 (1.84–2.11)*	2.05 (1.90–2.20)*
Compulsory testing^c					PCV: 21%
No	24375	4698	19%	ref	ref
Yes	832	80	10%	0.38 (0.30–0.48)*	0.43 (0.34–0.54)*
Test before surgery					PCV: 17%
No	20062	4113	21%	ref	ref
Yes	5145	665	13%	0.71 (0.65–0.78)*	0.71 (0.65–0.78)*
Test for non-STD clinic patients					PCV: 14%
No	15548	3254	21%	ref	ref
Yes	9659	1524	16%	0.80 (0.75–0.86)*	0.79 (0.73–0.84)*
Type of diagnosed institute
from STD clinic					PCV: -2%
No	82793	17652	21%	ref	ref
Yes	1145	446	39%	2.03 (1.80–2.29)*	2.43 (2.14–2.76)*
Hospital					PCV: 0%
No	15883	4159	26%	ref	ref
Yes	68061	13942	21%	0.80 (0.76–0.83)*	0.79 (0.75–0.82)*
Diagnosed outside residential city					PCV: -2%
No	71385	15457	22%	ref	ref
Yes	12559	2644	21%	0.90 (0.86–0.95)*	0.80 (0.76–0.84)*
Diagnosed outside residential county					PCV: 0%
No	54969	11741	21%	ref	ref
Yes	28975	6360	22%	1.03 (0.99–1.06)	1.00 (0.96–1.04)

aOR adjusted odds ratio, C.I. confidence interval, PCV proportional change of variance, MSM men who have sex with men, STD sexually transmitted diseases, VCT voluntary counselling and testing
^aadjusted by age at diagnosis (continuous variable) and male gender (binary variable)
^badjusted by age at diagnosis (continuous variable) only
^cCompulsory testing for immigrant, prisoner (male and female), drug uses in drug rehabilitation, blood recipient, blood donor, blood seller, new army recruits, staff in entertainment sites
*p < 0.05

ISSN: 1471-2458