Table 3 Risk factors for reinfection: multivariable analysis with pfmdr1. Data from 1934 individuals in the AS-AQ trial arms and 1655 in the AL trial arms were analyzed using accelerated failure-time analysis. Regression coefficients are the ratio of time to reinfection, such that a coefficient > 1 indicates a longer time to reinfection. Covariates significantly associated with reinfection time after adjusting for EIR (p < 0.05) were included in the final model. The prevalence of pfcrt 76T also had a significant effect in a multivariable model with the same covariates (Additional file 1: Table S1) but could not be included in the same model with pfmdr1 86Y due to strong correlation between the two variables. Models assume a lognormal time to reinfection and random site effects
Covariate (unit) | AL multivariable model (N = 1655) EIR, age, dose, pfmdr1 86Y | AS-AQ multivariable model (N = 1934) EIR, age, pfmdr1 86Y | ||
|---|---|---|---|---|
Coefficient [ratio of reinfection times] (95% CI) | p value | Coefficient [ratio of reinfection times] (95% CI) | p value | |
Loge annual EIR | 0.81 (0.74, 0.90) | < 0.001 | 0.81 (0.75, 0.87) | < 0.001 |
Age (polynomial, years, > 20 grouped together) |  | < 0.001 |  | < 0.001 |
 age | 1.01 (0.93, 1.09) |  | 0.94 (0.88, 1.00) |  |
 (age)2 | 1.00 (0.99, 1.02) |  | 1.01 (1.00, 1.02) |  |
 (age)3 | 1.0001 (0.9992, 1.0009) |  | 0.9998 (0.9993, 1.0003) |  |
Lumefantrine dose (per 10 mg per kg increase) (AL arms only) | 1.03 (1.01, 1.06) | 0.002 | – | – |
pfmdr1 86Y prevalence (per 10% increase) | 1.04 (1.00, 1.09) | 0.059 | 0.97 (0.94, 0.99) | 0.012 |