Table 2.
Summary of the included studies
| Author | Follow up period | Previous Treatment received | No. of PRP injections | Measure of symptoms | Case Group (PRP) | Control Group | P Value |
|---|---|---|---|---|---|---|---|
| Y. Steffens et al. | 1 month | Not mentioned | 1 |
TDI Likert |
TDI: 6.7 point improvement Likert: 1.8 point improvement |
TDI: 0.5 improvement Likert: 0.3 improvement |
Difference in Likert p < 0.001 TDI case group p < 0.001 |
| CH Yan et al. | 3 months | Olfactory training and local treatment for 3 months | 3 |
TDI VAS |
TDI: 6.25 point improvement VAS: 3.63 point improvement |
TDI: 2.58 improvement VAS: 2.45 improvement |
Difference in TDI p = 0.047 Difference in VAS p = 0.167 |
| JR Lechien | 2 months | 67% had olfactory training for 3 months, while 45% and 42% local or oral treatment. | 1 |
TDI ODQ |
TDI: 5.7 point improvement ODQ: 10.3 point improvement |
N/A |
TDI 0.009 ODQ 0.001 |
| Abo El Naga H.A. et al. | 1 month | Olfactory training and local and/or oral treatment for 3 months | 3 | VAS | VAS: 5.8 point improvement | VAS: 1.84 point improvement | Difference in VAS p = 0.002 |