Long-term mental health outcomes after unintentional burns sustained during childhood: a retrospective cohort study

Table 1 Baseline demographic and pre-existing health status factors for burn and uninjured cohorts

Characteristics	Uninjured N (%)	Burn injury N (%)	P value
Total	46,548	11,967
Demographic
Gender
Male	29,238 (62.8)	7583 (63.4)	0.090
Age
0–4	27,061 (58.1)	6794 (56.8)	0.113
5–9	6966 (15.0)	1794 (15.0)
10–14	6792 (14.6)	1826 (15.3)
15–17	5729 (12.3)	1494 (12.5)
Aboriginality
Yes	2136 (4.6)	2196 (18.4)	< 0.001
Social disadvantage quintiles^a
Quintile 1 (most disadvantaged)	5826 (12.5)	2622 (21.9)	< 0.001
Quintile 2	11,740 (25.2)	3903 (32.6)
Quintile 3	8394 (18.0)	2393 (20.0)
Quintile 4	7860 (16.9)	1461 (12.2)
Quintile 5 (least disadvantaged)	12,484 (26.8)	1410 (11.8)
Remoteness^b
Major city	31,448 (67.6)	6184 (51.7)	< 0.001
Inner regional	4772 (10.3)	1262 (10.5)
Outer regional	5259 (11.3)	1932 (16.1)
Remote	2933 (6.3)	1379 (11.7)
Very remote	1784 (3.8)	1076 (9.0)
Health status
Any comorbidity (CCI ≥ 1)^c	526 (1.1)	263 (2.2)	< 0.001
Prior admission for mental health condition^d	29 (0.1)	35 (0.3)	< 0.001
Prior admission for self-harm	14 (0.0)	24 (0.2)	< 0.001
Prior admission for drugs/alcohol	10 (0.0)	12 (0.1)	< 0.001
Congenital abnormality	1114 (2.4)	375 (3.1)	< 0.001

^aSocio-Economic Index for Areas (SEIFA) socio-economic disadvantage quintiles; missing values 1.0% burn, 0.5% no injury
^bAccessibility Remoteness Index of Australia, revised version (ARIA+) remoteness classification; missing values 0.6% burn, 0.8% no injury
^cComorbidity based on derived Charlson Comorbidity Index (CCI) using 5-year look-back period
^dPrincipal diagnosis record of hospitalisation for mental health condition using 5-year look-back period