Table 5.
Univariable and multivariable risk factors for parasite positivity on day 3
| Univariable analysis | Multivariable analysisc | |||||
|---|---|---|---|---|---|---|
| Variable | N (n)a | Random effectsb | Crude OR (95 % CI) | P value | Adjusted OR (95 % CI) | P value |
| Baseline parasitaemia (2-fold rise) | 28,580 (253) | 2.57 | 1.18 (1.10–1.28) | <0.001 | 1.16 (1.08–1.25) | <0.001 |
| Baseline anaemia | ||||||
| Non-anaemic (reference)d | 9,368 (60) | 2.50 | 1 | - | - | - |
| Moderate | 9,926 (86) | 1.14 (0.80–1.61) | 0.473 | 1.14 (0.80–1.61) | 0.476 | |
| Severe | 1,697 (23) | 1.94 (1.15–3.25) | 0.012 | 2.04 (1.21–3.44) | 0.008 | |
| Unknown | 7,589 (84) | 1.08 (0.55–2.13) | 0.827 | - | - | |
| Gametocytes presence | ||||||
| No (reference) | 19,561 (168) | 3.20 | 1 | - | - | - |
| Yes | 2,038 (17) | 1.10 (0.63–1.91) | 0.747 | - | - | |
| Febrile on presentation (temperature >37.5 °C) | ||||||
| No (reference) | 9,874 (46) | 2.27 | 1 | - | - | - |
| Yes | 17,678 (207) | 1.68 (1.19–2.38) | 0.003 | 1.50 (1.06–2.13) | 0.022 | |
| Gender | ||||||
| Female (reference) | 13,439 (106) | 2.56 | 1 | - | - | - |
| Male | 14,511 (142) | 1.22 (0.94–1.58) | 0.134 | - | - | |
| Age category | ||||||
| ≥12 years (reference) | 4,639 (36) | 2.55 | 1 | - | - | - |
| <1 year | 2,027 (20) | 1.51 (0.75–3.03) | 0.247 | 1.25 (0.62–2.55) | 0.530 | |
| 1 to <5 years | 16,060 (130) | 1.23 (0.72–2.10) | 0.453 | 1.09 (0.64–1.87) | 0.753 | |
| 5 to <12 years | 5,818 (66) | 1.74 (1.09–2.76) | 0.019 | 1.56 (0.98–2.48) | 0.061 | |
| Transmission settings | ||||||
| High (reference) | 10,377 (66) | 2.38 | 1 | - | - | - |
| Low/moderate | 18,203 (187) | 2.34 (1.14–4.80) | 0.021 | 2.71 (1.38–5.36) | 0.004 | |
| Treatmente | ||||||
| DP (reference) | 4,434 (34) | 2.01 | 1 | - | - | - |
| AL | 13,004 (76) | 0.93 (0.57–1.51) | 0.765 | 0.93 (0.57–1.52) | 0.774 | |
| ASAQ-FDC | 4,999 (27) | 0.70 (0.38–1.31) | 0.269 | 0.67 (0.36–1.25) | 0.206 | |
| ASAQ-coblistered NFDC | 1,851 (44) | 2.23 (0.69–7.22) | 0.183 | 2.87 (0.89–9.27) | 0.078 | |
| ASAQ-loose NFDC | 4,292 (72) | 2.27 (1.12–4.60) | 0.023 | 2.27 (1.14–4.51) | 0.020 | |
aN = number of patients with non-missing data; n = number of patients with positive blood smear on day 3; bvariance of the random effects for the respective univariable analyses; cN = 27,520 for the final multivariable model with 252 cases of positive parasitaemia. Likelihood ratio test for random effect (P <0.001). Variance of random effect = 1.72. Proportion of total variance contributed by the site-level variance component (ρ) = 0.35. Coefficient (standard error) of intercept = −9.07 (0.7084). The coefficient of variation in parameter estimates was calculated by excluding one study site at a time and expressed as relative standard deviation (RSD). The RSD is shown in Additional file 4: Table S9; dmultiple imputation was performed on missing anaemia status using ordinal logistic regression with age, gender and parasitaemia as covariates. The estimates derived using 100 imputations for moderate and severe anaemia are: AOR = 1.11 (95 % CI: 0.80–1.54), P = 0.523 and AOR = 1.62 (95 % CI: 0.99–2.66), P = 0.057, respectively; efor ASAQ-loose NFDC: AOR = 2.27 (95 % CI: 1.14–4.51), P = 0.020 compared to DP and AOR = 3.36 (95 % CI: 1.61–6.98), P = 0.001 compared to ASAQ-FDC. For ASAQ-coblistered NFDC, AOR = 4.18 (95 % CI: 1.28–13.68), P = 0.017 compared to ASAQ-FDC. AL, artemether-lumefantrine; AS-AQ, artesunate-amodiaquine; ASAQ-coblistered NFDC, non-fixed dose combination in a co-blister formulation; ASAQ-FDC, fixed dose combination; ASAQ-loose NFDC, non-fixed dose combination in a loose formulation; DP, dihydroartemisinin-piperaquine