Table 12.

Effect of duration of storage and parasite density on the sensitivity for each Plasmodium species, multivariate analysis

	Odds Ratio	P	95% CI
P. falciparum (n = 320)
Number of years of storage	0.97	0.675	0.86-1.10
Log10 parasite densities	2.04	0.000	1.50-2.76
P. vivax (n = 76)
Number of years of storage	0.94	0.451	0.79-1.11
Log10 parasite densities	3.56	0.003	1.55-8.18
P. ovale (n = 76)
Number of years of storage	0.73	0.003	0.60-0.90
Log10 parasite densities	12.19	0.005	2.12-70.23
P. malariae (n = 23)
Number of years of storage	0.80	0.185	0.57-1.12
Log10 parasite densities	33.10	0.029	1.43-768.88

The decline in sensitivity in relation to low parasite density and long duration of storage was expressed by Odds ratios.