Table 3 Sources of heterogeneity assessment based on meta-regression analyses (93 geo-referenced locations)
Factors | Summary statistics | Pooled correlation (rho) | 95% CI | p value | Residual I2 (%) | Percentage change in I2 (%) |
|---|---|---|---|---|---|---|
Geographical region, n (%) | ||||||
 Eastern Africa | 42 (45.2%) | 0.43 | 0.18, 0.62 | 0.01 | 67.7 | 2.8 |
 Southern Africa | 23 (24.7%) | 0.33 | 0.07, 0.54 | |||
 Western Africa | 22 (23.7%) | 0.73 | 0.53, 0.86 | |||
 Central Africa | 4 (4.3%) | 0.30 | − 0.42, 0.79 | |||
 Horn of Africa | 2 (2.1%) | 0.84 | 0.60, 0.94 | |||
Quality of the study, n (%) | ||||||
 High risk of bias | 28 (30.1%) | 0.54 | 0.30, 0.71 | < 0.001 | 63.2 | 9.3 |
 Moderate risk of bias | 41 (44.1%) | 0.25 | 0.02, 0.46 | |||
 Low risk of bias | 24 (25.8%) | 0.78 | 0.63, 0.87 | |||
Data source, n (%) | ||||||
 In-patient | 34 (36.6%) | 0.36 | 0.07, 0.59 | 0.01 | 68.1 | 2.3 |
 In-patient and out-patient | 17 (18.3%) | 0.38 | 0.03, 0.65 | |||
 Out-patient | 42 (45.1%) | 0.67 | 0.52, 0.78 | |||
Measure of malaria, n (%) | ||||||
 Number of cases reported | 30 (32.3%) | 0.26 | − 0.01, 0.49 | 0.001 | 66.2 | 4.9 |
 Test positive rate | 47 (50.5%) | 0.69 | 0.54, 0.79 | |||
 Incidence rate | 16 (17.2%) | 0.30 | − 0.06, 0.59 | |||
Average starting parasite prevalence in children aged 2–10 years | ||||||
 < 10% | 19 (20.4%) | 0.33 | − 0.08, 0.64 | 0.002 | 66.2 | 4.9 |
 10–50% | 55 (59.2%) | 0.64 | 0.50, 0.75 | |||
 > 50% | 19 (20.4%) | 0.11 | − 0.20, 0.41 | |||
Sample size, median (IQR) | 15,779 (3957, 35,981) | 0.01 | − 0.09, 0.11 | 0.83 | 71.8 | − 3.1 |
Sum of residuals of empirical clinical incidence/test positivity rate, median (IQR) | 0.94 (0.06, 2.05) | 0.07 | − 0.03, 0.17 | 0.07 | 69.3 | 0.5 |
Sum of residuals of MAP modelled clinical incidence, median (IQR) | 0.12 (0.06, 0.30) | − 0.02 | − 0.65, 0.62 | 0.24 | 69.8 | − 0.3 |
Slope of empirical clinical incidence/test positivity rate, median (IQR) | − 0.003 (− 0.16, 0.001) | − 0.989 | − 0.998, − 0.939 | < 0.001 | 58.8 | 15.5 |
Slope of modelled MAP clinical incidence, median (IQR) | − 0.02 (− 0.03, 0.0001) | − 0.99995 | − 1.00, − 0.997 | 0.003 | 67.5 | 3.1 |