Table 4 Multivariate models of the spirometry parameters (% of predicted) and the risk for disability pension. Hazard ratios (HR) and confidence intervals (95% CI) are calculated using Cox regression. The total number of study subjects is 3386 and the number of the participants in each quartile is 846 or 847. Each quartile’s range of the spirometry parameter is in paracenteses

 highest quartile (104.23–123.24)

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 3rd quartile (100.15–104.22)

1.07 (0.79–1.45)

1.04 (0.76–1.40)

1.01 (0.74–1.37)

1.03 (0.76–1.40)

1.00 (0.74–1.36)

 2nd quartile (95.76–100.14)

1.18 (0.87–1.60)

1.14 (0.84–1.53)

1.08 (0.80–1.45)

1.20 (0.89–1.62)

1.17 (0.86–1.58)

 lowest quartile (53.42–95.75)

1.42 (1.06–1.90)

1.41 (1.06–1.89)

1.27 (0.96–1.70)

1.44 (1.07–1.93)

1.35 (1.00–1.83)

 highest quartile (109.41–151.59)

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 3rd quartile (101.56–109.40)

1.29 (0.94–1.78)

1.15 (0.84–1.58)

1.27 (0.92–1.74)

1.31 (0.95–1.80)

1.31 (0.95–1.81)

 2nd quartile (93.22–101.55)

1.26 (0.92–1.75)

1.10 (0.79–1.51)

1.18 (0.86–1.63)

1.24 (0.90–1.71)

1.21 (0.87–1.68)

 lowest quartile (40.16–93.21)

1.92 (1.43–2.57)

1.63 (1.21–2.19)

1.85 (1.38–2.47)

1.73 (1.28–2.32)

1.66 (1.23–2.24)

 highest quartile (108.89–141.78)

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 3rd quartile (101.26–108.88)

1.18 (0.86–1.63)

1.09 (0.79–1.50)

1.21 (0.88–1.67)

1.18 (0.86–1.63)

1.19 (0.86–1.64)

 2nd quartile (93.43–101.25)

1.37 (1.00–1.87)

1.22 (0.89–1.67)

1.29 (0.95–1.77)

1.30 (0.95–1.78)

1.33 (0.97–1.82)

 lowest quartile (45.51–93.42)

1.66 (1.23–2.23)

1.48 (1.10–2.00)

1.78 (1.33–2.39)

1.50 (1.11–2.03)

1.49 (1.10–2.01)