Table 6.
Stratification meta-analysis according to the type of stevia extract for FRAP, ABTS, and ORAC assays.
| Assay | Type of Extract | Effect Size | CI 95% | Number of Studies |
|---|---|---|---|---|
| FRAP all units | Aqueous | 320.02 | 194.79, 445.23 | 3 |
| Hydroalcoholic | 855.54 | 687.10, 1024.0 | 10 | |
| Organic | 248.40 | 221.63, 275.17 | 6 | |
| FRAP µmol Fe+2/g | Aqueous | 210.00 | 204.33, 215.66 | 1 |
| Hydroalcoholic | nr* | |||
| Organic | 248.40 | 221.63, 275.17 | 6 | |
| FRAP µmol TE/g | Aqueous | 375.84 | 70.08, 681.59 | 2 |
| Hydroalcoholic | 855.53 | 687.1, 1023.9 | 10 | |
| Organic | nr* | |||
| FRAP hydroalcoholic | Ethanol 12% | 230.00 | 226.61, 233.39 | 1 |
| (alcohol %) | Ethanol 50% | 1192.51 | 943.09, 1441.9 | 6 |
| Ethanol 70% | 430.93 | 250.17, 611.71 | 3 | |
| ABTS μmol TE/g | Aqueous | 680.00 | 668.69, 691.30 | 1 |
| Hydroalcoholic | 581.44 | 435.54, 727.35 | 2 | |
| Organic | 313.64 | 299.14, 328.14 | 2 | |
| ORAC µmol TE/g | Aqueous | 879.28 | 677.37, 1081.2 | 8 |
| Hydroalcoholic | 454.90 | 453.65, 456.12 | 2 | |
| Organic | nr* | |||
| Meta-analysis of FRAP, ABTS, and ORAC | ||||
| Aqueous | 769.20 | 587.98, 950.43 | 11 | |
| Hydroalcoholic | 720.48 | 645.31, 795.65 | 14 | |
| Organic | 313.64 | 299.14, 328.15 | 2 | |
nr*: not reported; CI 95%: 95% confidence interval; TE: Trolox equivalent; Hydroalcoholic: a solvent mixture of water and alcohol.