Table 1.
Characteristics of the included studies
| Characteristics | N | % |
|---|---|---|
| Study designs | ||
| Case–control studies | 8 | 40 |
| Cross-sectional studies | 6 | 30 |
| Prospective observational studies | 5 | 25 |
| Cohort study | 1 | 5 |
| Study areas | ||
| Africa | 10 | 50 |
| South America | 4 | 20 |
| Asia and Oceania | 3 | 15 |
| Europe | 2 | 10 |
| North America | 1 | 5 |
| Plasmodium spp. | ||
| P. falciparum | 13 | 65 |
| P. falciparum/P. vivax | 4 | 20 |
| P. vivax | 2 | 10 |
| P. knowlesi/P. falciparum | 1 | 5 |
| Participants | ||
| Children | 11 | 55 |
| Adults | 7 | 35 |
| All age groups | 2 | 10 |
| Methods for malaria detection | ||
| Microscopy | 16 | 80 |
| Microscopy/PCR | 4 | 20 |
| Methods for TGF-β quantification | ||
| Bead-based assay | 13 | 65 |
| ELISA | 7 | 35 |
ELISA enzyme-linked immunosorbent assay, PCR polymerase chain reaction