Table 2.
Time intervals | Obs | Exp | Adjusted RRb (95% confidence interval) |
---|---|---|---|
All (4442) | 850 | 400.3 | 2.3 (2.2–2.5) |
1st month (96) | 113 | 12.5 | 18.4 (13.9–24.5) |
1–11 months (308) | 70 | 18.5 | 4.4 (3.4–5.7) |
1–4 years (1172) | 173 | 78.0 | 2.4 (2.0–2.8) |
5–9 years (1102) | 180 | 96.2 | 2.0 (1.7–2.4) |
10–19 years (1303) | 241 | 144.9 | 1.8 (1.6–2.0) |
20+ years (461) | 73 | 50.2 | 1.5 (1.2–2.0) |
aConditions used in the reference cohort with ICD9 code for diagnosis (with equivalent codes used for other coding editions): varicose veins (454), haemorrhoids (455), upper respiratory tract infections (460), deflected septum, nasal polyp (470–471), impacted tooth and disorders of teeth (520–521), inguinal hernia (550), in-growing toenail and other diseases of nail (703), sebaceous cyst (706.2), internal derangement of knee (717), bunion (727.1), squint (378), otitis externa and otitis media (380–382), selected fractures (810–816, 823–826), dislocations sprains and strains (830–839, 840–848) and superficial injury and contusion (910–919, 920–924).
bAdjusted for age in 5-year age bands, time period in single calendar years and district of residence; comparing Obs/Exp in the BBD cohort (data in table) with Obs/Exp in the reference cohort (data not shown separately).