Table 2.
A summary of WMD for the overall and 95% CIs of vitamin D and CRS.
| Subgroup | Nº of studies | Nº of patients | Nº of controls | WMD (95% CI) | p-value | Heterogeneity I2 (%) |
|---|---|---|---|---|---|---|
| Overall | 8 | 337 | 179 | −7.80 (−13.28 to −2.31) | 0.000 | 84.4 |
| Phenotype | ||||||
| CRSwNP | 8 | 220 | 179a | −15.21 (−26.16 to −4.25) | 0.000 | 97.1 |
| CRSsNP | 5 | 117 | 89a | −4.04 (−6.38 to −1.69) | 0.226 | 29.3 |
| Biomarker | ||||||
| 25(OH)D3 | 6 | 246 | 95 | −9.77 (−15.81 to −3.73) | 0.001 | 75.5 |
| 25(OH)D | 2 | 91 | 84 | −3.33 (−15.36 to 8.69) | 0.000 | 93.0 |
| Geographic area | ||||||
| USA | 4 | 149 | 55 | −6.67 (−14.00 to 0.65) | 0.002 | 79.5 |
| Non-USA | 4 | 188 | 124 | −9.61 (−19.17 to −0.05) | 0.000 | 89.0 |
| Study design | ||||||
| Retrospective | 5 | 216 | 76 | −8.01 (−13.88 to −2.13) | 0.005 | 73.5 |
| Prospective | 3 | 121 | 103 | −9.10 (−21.25 to 3.05) | 0.000 | 91.8 |
95% CI, 95% confidence intervals; WMD, weighted mean difference; CRSwNP, chronic rhinosinusitis with nasal polyps; CRSsNP, chronic rhinosinusitis without nasal polyps; 25(OH)D, 25-Hydroxyvitamin D.
a
Most of the included studies compared both the CRSwNP and CRSsNP with controls, leading to the number of controls were repeatedly counted.