Table 2.

Factors associated with 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	98 (40.2)	Reference	–	Reference	–
	Middle	133 (52.8)	1.31 (1.08–1.59)	0.005	1.15 (0.95–1.39)	0.15
	Poorest	154 (59.9)	1.49 (1.24–1.79)	< 0.001	1.29 (1.07–1.55)	0.008
Type of house constructionb	Modern	61 (35.5)	Reference	–	Reference	–
	Traditional	324 (55.8)	1.57 (1.27–1.95)	< 0.001	1.41 (1.14–1.74)	0.002
Whether airbricks were present	Present	79 (37.8)	Reference	–	Reference	–
	Not present	306 (56.3)	1.49 (1.23–1.80)	< 0.001	1.09 (0.86–1.39)	0.48
Number of windows present	≥ 2 windows	65 (45.1)	Reference	–	Reference	–
	1 window	224 (50.1)	1.11 (0.91–1.36)	0.31	0.97 (0.79–1.18)	0.73
	No windows	96 (59.3)	1.31 (1.05–1.64)	0.02	1.06 (0.84–1.32)	0.63
Level of education	O level or beyond	86 (46.2)	Reference	–	Reference	–
	None or primary	299 (52.7)	1.14 (0.96–1.36)	0.14	1.13 (0.95–1.34)	0.17
Bed net ownership before enrolment	LLIN	285 (49.2)	Reference	–	Reference	–
	Untreated	62 (56.9)	1.16 (0.96–1.39)	0.12	1.07 (0.90–1.28)	0.45
	No bed net	38 (58.5)	1.19 (0.95–1.48)	0.13	1.03 (0.83–1.28)	0.77
Categories of gravidity	Multigravida	145 (38.0)	Reference	–	Reference	–
	Secundigravida	108 (57.8)	1.52 (1.27–1.82)	< 0.001	1.53 (1.28–1.82)	< 0.001
	Primigravida	132 (71.7)	1.89 (1.62–2.21)	< 0.001	1.84 (1.58–2.16)	< 0.001

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