. 2018 Sep 4;99(4):995–1002. doi: 10.4269/ajtmh.18-0417

Table 3.

Logistic regression analysis of Plasmodium falciparum infection explanatory variables

			P. falciparum (microscopy-detectable)							P. falciparum (molecularly diagnosed)							P. falciparum (submicroscopic)
				Univariable model			Multivariable model				Univariable model			Multivariable model				Univariable model			Multivariable model
		N^*	PfPR^†	OR	95% CI^‡	P	AOR	95% CI^‡	P	PfPR^†	OR	95% CI^‡	P	AOR	95% CI^‡	P	PfPR^†	OR	95% CI^‡	P	AOR	95% CI^‡	P
Gender	Female	1,086	2.6%		Reference					7.0%		Reference					5.2%		Reference
Gender	Male	977	1.9%	0.75	(0.41–1.34)	0.3400				7.1%	1.01	(0.72–1.42)	0.95				5.4%	1.06	(0.72–1.55)	0.790
Age (year)		2,061	2.3%	0.99	(0.97–1.01)	0.3800				7.0%	1.00	(0.99–1.01)	0.79				4.8%	1.00	(0.99–1.01)	0.600
Exposure (year)^§		2,050	2.3%	0.99	(0.93–1.05)	0.7600	Not selected			7.0%	0.98	(0.95–1.02)	0.35				4.8%	0.98	(0.94–1.02)	0.400
														Not selected								Not selected
	Other	103	3.9%		Reference					10.7%		Reference					6.8%		Reference
Ethnicity^‖	Betsileo	455	1.8%	0.45	(0.13–2.10)	0.5100				7.0%	0.67	(0.31–1.62)	0.53				5.5%	0.86	(0.34–2.61)	0.860
	Merina	1,505	2.3%	0.60	(0.21–2.54)					6.8%	0.65	(0.32–1.49)					5.1%	0.80	(0.34–2.32)
Water distance (m)^¶		2,063	2.3%	1.00	(1.00–1.00)	0.0005	1.00	(1.00–1.00)	0.012	7.0%	1.00	(1.00–1.00)	0.043				4.8%	1.00	(1.00–1.00)	0.480
Insecticide-treated bednet ownership	No	242	5.0%		Reference			Reference		17.4%		Reference			Reference		12.8%		Reference			Reference
Insecticide-treated bednet ownership	Yes	1,810	1.9%	0.37	(0.19–0.75)	0.0035	0.31	(0.14–0.70)	0.004	5.6%	0.28	(0.19–0.42)	< 0.0001	0.39	(0.26–0.59)	< 0.0001	4.3%	0.31	(0.20–0.48)	< 0.0001	0.43	(0.28–0.68)	0.0002
	Center	775	1.2%		Reference			Reference		1.9%		Reference			Reference		1.0%		Reference			Reference
Health center	North	492	1.2%	1.05	(0.35–2.93)	0.0004	0.49	(0.14–1.50)	0.043	7.3%	4.00	(2.21–7.60)	< 0.0001	3.02	(1.61–5.96)	< 0.0001	6.1%	6.23	(2.97–14.68)	< 0.0001	5.31	(2.51–12.60)	< 0.0001
Health center	South	796	4.0%	3.56	(1.76–7.99)		1.72	(0.72–4.33)		11.8%	6.78	(4.02–12.28)		5.98	(3.46–11.13)		8.9%	9.39	(4.77–21.29)		8.22	(4.14–18.73)
Fever^#	No	1,904	2.0%		Reference			Reference		6.5%		Reference			Reference		5.0%		Reference			Not selected
Fever^#	Yes	111	6.3%	3.22	(1.29–6.95)	0.0057	3.79	(1.46–8.74)	0.003	16.2%	2.78	(1.58–4.65)	0.0002	2.56	(1.25–3.91)	0.0051	9.9%	2.07	(1.02–3.83)	0.029		Not selected

AOR = adjusted odds ratios; CI = confidence interval; OR = odds ratio; PfPR = prevalence of Plasmodium falciparum. Each infection level was modeled separately, using univariable (OR) and multivariable (AOR) models.

Totals tested by category. Any totals less than 2,063 are because of incomplete information about the different fields.

^†

PfPR infection $(P f PR = \frac{Total positive}{Total tested}),$ including both mono- and mixed-species infections.

^‡

95% CI of the AOR. P values were derived from the Wald test and represent each categorical factor’s overall statistical significance. Significant P values (P < 0.05) are identified in bold.

^§

Exposure time corresponds to the total years of residency in the malaria-endemic area. Participants born in the study area are considered to have been exposed since birth.

^‖

Ethnicity is self-reported and inherited via the female line.

^¶

Distance to water as informed by the HydroSHEDS river network dataset.^20,21

Fever was present if axillary temperature was ≥ 37.5°C.