Table 4.
Standardized mean differences in PC20 related to environmental strategy in the meta‐analysis by Gøtzsche and Johansen37
| Strategy | SMD | 95% CI | Patients (n) | P‐value | I 2 |
|---|---|---|---|---|---|
| Sojourn high altitude | NA | NA | NA | NA | NA |
| Total avoidance | NA | NA | NA | NA | NA |
| Exposure‐based | NA | NA | NA | NA | NA |
| Concurrent bedroom | 0.05 | −0.09 to 0.20 | 475 | 0.45 | 0% |
| 1 barrier | 0.05 | −0.20 to 0.30 | 254 | 0.68 | 0% |
| 2‐3 barriers | 0.05 | −0.21 to 0.32 | 221 | 0.69 | 0% |
| Air purification | −0.12 | −1.05 to 0.80 | 18 | 0.80 | 0% |
| Mixed strategies | 0.05 | −0.13 to 0.22 | 493 | 0.61 | 0% |
| Gøtzsche & Johansena | 0.05 | −0.13 to 0.22 | 493 | 0.61 | 0% |
a
Standardized mean differences as calculated by Gøtzsche and Johansen37 with a fixed‐effect model.