Table 3.

Analysis of the variables identified as risk factors potentially involved in the transmission of Giardia duodenalis, Cryptosporidium spp. and Blastocystis spp. in Cubal, Angola, 2015. Combined results for all protozoan parasites are shown. Prevalence risk ratios (PRR) and 95% confidence intervals (CIs) are indicated

Variable (no. of missing observations)	Category	Casesa	Non-casesb	PRR	95% CI	P
Gender (0)	Male	87	62	1.18	0.97–1.43	0.099
	Female	100	102	Reference
Age group (0)	≤ 7 years old	66	35	1.35	1.12–1.63	0.004
	>  7 years old	121	129	Reference
Household size (9)	>  6 individuals	78	82	0.86	0.70–1.06	0.147
	≤ 6 individuals	103	79	Reference
Bath place (1)	Otherc	111	82	1.20	0.98–1.47	0.069
	Home	75	82	Reference
Contact with domestic animals (10)	Exposed	149	130	0.94	0.74–1.20	0.619
	Unexposed	35	27	Reference
Drinking water source (0)	Otherd	152	134	0.99	0.77–1.27	0.918
	Tap water	35	30	Reference
Eating raw vegetables/fruits (0)	Yes	174	144	1.39	0.90–2.14	0.093
	No	13	20	Reference
Raw vegetables/fruits washing (33)	No	37	31	1.00	0.78–1.28	0.998
	Yes	136	114	Reference
Body mass indexe (10)	≤ P5	56	72	0.74	0.59–0.93	0.005
	> P5	126	87	Reference
Haemoglobin levele (14)	≤ 11 g/dl	60	43	1.14	0.92–1.40	0.237
	>  11 g/dl	120	114	Reference

^aCases: samples that tested positive for G. duodenalis, Cryptosporidium spp. or Blastocystis spp. by PCR-based methods

^bNon-cases: samples that tested negative for G. duodenalis, Cryptosporidium spp. or Blastocystis spp. by PCR-based methods

^cStreet, river

^dRainwater, surface water and groundwater

^eSee Methods section