Association between humidifier disinfectant exposure during infancy and subsequent neuropsychiatric outcomes during childhood: a nation-wide cross-sectional study

Table 1 Baseline demographics of the study subjects

	Total (n = 1113)	Non-HD (n = 717, 64.4%)	HD (n = 396, 35.6%)	P value
Maternal age (years), mean (SD)	31.16 (3.5)	31.38 (3.5)	30.76 (3.4)	0.046
Paternal age (years), mean (SD)	33.61 (3.8)	33.71 (3.9)	33.43 (3.7)	0.051
Birth weight (kg), mean (SD)^a	3.26 (0.42)	3.25 (0.42)	3.28 (0.41)	0.654
Gender, n (%)				0.896
Boy	562 (50.5)	361 (50.3)	201 (50.8)
Girl	551 (49.5)	356 (49.7)	195 (49.2)
Infant’s birth order, n (%)				0.323
Firstborn	554 (49.8)	349 (48.7)	205 (51.8)
Later-born	559 (50.2)	368 (51.3)	191 (48.2)
Household income, n (%)^b				0.191
I (<1639US$)	302 (27.2)	191 (26.6)	111 (28.1)
II (1639–2458US$)	384 (34.5)	250 (34.9)	134 (33.9)
III (2459–3278US$)	226 (20.3)	136 (19.0)	90 (22.8)
IV(>3279US$)	200 (18.0)	140 (19.5)	60 (15.2)
Maternal education level, n (%)				0.176
High school	341 (30.6)	223 (31.1)	118 (29.8)
College	328 (29.5)	198 (27.6)	130 (32.8)
University	444 (39.9)	295 (41.3)	148 (37.4)
Maternal smoking, n (%)				0.148
No	1084 (97.4)	702 (97.9)	382 (96.5)
Yes	29 (2.6)	15 (2.1)	14 (3.5)
Maternal alcohol drinking, n (%)				0.784
No	467 (42.0)	303 (42.3)	164 (41.4)
Yes	646 (58.0)	414 (57.7)	232 (58.6)
Paternal education level, n (%)				0.582
High school	297 (26.7)	184 (25.4)	113 (28.5)
College	264 (23.7)	172 (24.0)	92 (23.2)
University	552 (49.6)	361 (50.3)	191 (48.2)
Paternal smoking, n (%)^c				0.540
No	558 (50.2)	365 (50.9)	193 (49.0)
Yes	553 (49.8)	352 (49.1)	201 (51.0)
Paternal alcohol drinking, n (%)^d				0.388
No	240 (21.8)	161 (22.6)	79 (20.4)
Yes	860 (78.2)	551 (77.4)	309 (79.6)

ISSN: 1471-2431