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Table 2 in the original article summarizing the within‐subject variance across previously published studies had calculation errors. These errors have been corrected and are presented below in the revised Table 2.
Table 2.
Estimate of Within‐Subject Variance From Previously Published Studies
| Authors (Reference) | Drug Studieda | Within‐Subject Varianceb |
|---|---|---|
| Ahrens et al6 | SABA | 1.125 |
| Prabhakaran et al9 | LABA | 0.187 |
| Parameswaran et al10 | SABA | 0.115 |
| Higham et al11 | SABA | 1.584 |
| Inman et al12 | SABA | 0.583 |
| Giannini et al13 | SABA | 1.988 |
| Creticos et al14 | SABA | 0.552 |
| Langley et al15 | LABA | 1.928 |
| Allan et al16 | LABA | 0.718 |
SABA indicates short‐acting beta agonist (albuterol); LABA indicates long‐acting beta agonist (formoterol or salmeterol).
Obtained from data in publication, complete data set14; s/b ratio (where s is the within‐subject error and b is the dose‐response slope)6,10; treatment effect expressed as “doubling doses” relative to placebo9,11‐13,15 or within‐subject variance.16
The revisions in Table 2 will also result in a correction in the Discussion section of the article on page 463. The corrected sentence should read: “Within‐subject variance observed in prior work ranged from 0.115 to 1.988 (Table 2).6,9‐16”