Table 2.
Incidence of episodes of acute dermatolymphangioadenitis, overall and by quarter
|
Intervention group (n=350) |
Control group (n=346) |
Incidence ratio (95% CI)* | Incidence difference (95% CI) | |||||
|---|---|---|---|---|---|---|---|---|
| Person-years | Number of events | Incidence† (95% CI) | Person-years | Number of events | Incidence† (95% CI) | |||
| Overall | 387·1 | 7515 | 19·4 (18·9–19·9) | 378·1 | 9035 | 23·9 (23·4–24·4) | 0·81 (0·74 to 0·89) | −4·5 (−5·1 to −3·8) |
| Q1 | 102·3 | 1227 | 12·0 (11·3–12·7) | 102·1 | 1642 | 16·1 (15·3–16·9) | 0·75 (0·63 to 0·88) | −4·1 (−5·1 to −3·1) |
| Q2 | 100·1 | 2492 | 24·9 (23·9–25·9) | 100·0 | 2903 | 29·0 (27·9–30·1) | 0·86 (0·77 to 0·95) | −4·1 (−5·6 to −2·7) |
| Q3 | 97·5 | 2182 | 22·4 (21·5–23·3) | 96·9 | 2555 | 26·4 (25·3–27·4) | 0·85 (0·78 to 0·94) | −4·0 (−5·4 to −2·6) |
| Q4 | 87·2 | 1614 | 18·5 (17·6–19·4) | 79·0 | 1935 | 24·5 (23·4–25·6) | 0·76 (0·66 to 0·86) | −6·0 (−7·4 to −4·6) |
*
Calculated by use of Poisson regression, to account for participant clustering of events.
†
Episodes per person-year.