Table 3.

Factors associated with microscopic or sub-microscopic parasitaemia at enrolment

Variable	Categories	Parasitaemia n (%)	Univariate analysis		Multivariate analysis
			RR (95% CI)	p-value	aRRa (95% CI)	p-value
Wealth index categories	Least poor	179 (73.4)	Reference	–	Reference	–
	Middle	215 (85.3)	1.16 (1.06–1.27)	0.001	1.07 (0.98–1.16)	0.16
	Poorest	222 (86.4)	1.18 (1.08–1.29)	< 0.001	1.09 (0.99–1.19)	0.07
Type of house constructionb	Modern	111 (64.5)	Reference	–	Reference	–
	Traditional	505 (86.9)	1.35 (1.20–1.51)	< 0.001	1.29 (1.15–1.45)	< 0.001
Whether airbricks were present	Present	147 (70.3)	Reference	–	Reference	–
	Not present	469 (86.2)	1.23 (1.12–1.35)	< 0.001	0.96 (0.85–1.08)	0.49
Number of windows present	≥ 2 windows	114 (79.2)	Reference	–	Reference	–
	1 window	360 (80.5)	1.02 (0.92–1.12)	0.73	0.96 (0.87–1.05)	0.35
	No windows	142 (87.7)	1.11 (1.00–1.23)	0.05	0.98 (0.88–1.08)	0.65
Level of education	O level or beyond	134 (72.0)	Reference	–	Reference	–
	None or primary	482 (85.0)	1.18 (1.07–1.30)	0.001	1.13 (1.02–1.24)	0.02
Bed net ownership before enrolment	LLIN	472 (81.5)	Reference	–	Reference	–
	Untreated	88 (80.7)	0.99 (0.90–1.09)	0.85	0.96 (0.87–1.06)	0.45
	No bed net	56 (86.2)	1.06 (0.95–1.17)	0.30	1.01 (0.91–1.12)	0.87
Categories of gravidity	Multigravida	304 (79.6)	Reference	–	Reference	–
	Secundigravida	150 (80.2)	1.01 (0.92–1.10)	0.86	1.02 (0.94–1.11)	0.61
	Primigravida	162 (88.0)	1.11 (1.03–1.19)	0.007	1.10 (1.02–1.18)	0.009

RR risk ratio

^aAdjusted for wealth index, type of house construction, level of education, bed net ownership before enrolment and categories of gravidity

^bModern houses defined as those with plaster or cement walls, metal or wooden roof, and closed eaves; all other houses defined as traditional