Table 2 Significant differences between tropical, subtropical and temperate ISAAC centers
Outcome | Mean (SD), tropics | Mean (SD), subtropics | Mean (SD), temperate | p-value (difference between all groups) | Mean difference (tropics vs subtropics) | p-value (tropics vs subtropics) | Mean difference (tropics vs temperate) | p-value (tropics vs temperate) | Mean difference (subtropics vs temperate) | p-value (subtropics vs temperate) |
|---|---|---|---|---|---|---|---|---|---|---|
Current rhinitis: Whole Cohort | 29.5 (12.7) | 28.5 (11.8) | 25.0 (9.1) | 0.001 | 1.03 | NS | 4.47 | 0.001 | 3.44 | 0.028 |
Current rhinitis: Age 13–14 years | 32.6 (12.5) | 32.5 (12.1) | 29.4 (8.5) | NS | 0.01 | NS | 3.12 | NS | 3.11 | NS |
Current rhinitis: Age 6–7 years | 24.1 (11.2) | 21.8 (7.9) | 18.5 (5.4) | 0.002 | 2.31 | NS | 5.58 | <0.001 | 3.28 | NS |
Change per year in Current rhinitis: Whole Cohort | 0.26 (1.03) | 0.93 (1.30) | 0.32 (0.93) | 0.02 | −0.67 | 0.01 | −0.06 | NS | 0.61 | 0.009 |
Change per year in Current rhinitis: Age 13–14 years | 0.26 (1.15) | 1.07 (1.46) | 0.29 (1.11) | 0.046 | −0.81 | 0.03 | −0.04 | NS | 0.78 | 0.018 |
Change per year in Current rhinitis: Age 6–7 years | 0.26 (0.84) | 0.59 (0.77) | 0.36 (0.56) | NS | −0.33 | NS | −0.10 | NS | 0.23 | NS |
Hay Fever Ever: Whole Cohort | 18.9 (13.3) | 21.2 (15.2) | 14.6 (10.7) | <0.001 | −2.14 | NS | 4.37 | 0.004 | 6.51 | <0.001 |
Hay Fever Ever: Age 13–14 years | 20.8 (14.6) | 24.2 (14.5) | 18.4 (11.7) | NS | −3.39 | NS | 2.44 | NS | 5.83 | 0.017 |
Hay Fever Ever: Age 6–7 years | 15.7 (10.1) | 16.0 (15.2) | 9.0 (5.5) | <0.001 | −0.31 | NS | 6.70 | <0.001 | 7.01 | 0.002 |
Change per year in Hay Fever Ever: Whole Cohort | 0.86 (1.60) | 0.69 (1.05) | 0.37 (0.61) | 0.025 | 0.18 | NS | 0.49 | 0.01 | 0.31 | NS |
Change per year in Hay Fever Ever: Age 13–14 years | 0.95 (1.72) | 0.76 (1.17) | 0.38 (0.70) | NS | −0.19 | NS | 0.58 | 0.033 | −0.38 | NS |
Change per year in Hay Fever Ever: Age 6–7 years | 0.73 (1.46) | 0.47 (0.62) | 0.36 (0.47) | NS | 0.25 | NS | 0.37 | NS | 0.11 | NS |
Current rhinoconjunctivitis: Whole Cohort | 13.1 (6.9) | 13.3 (7.4) | 10.7 (5.3) | 0.001 | −0.13 | NS | 2.43 | 0.001 | 0.26 | 0.005 |
Current rhinoconjunctivitis: Age 13–14 years | 15.2 (6.9) | 16.1 (7.3) | 13.2 (5.0) | 0.015 | −0.95 | NS | 2.00 | 0.031 | 2.95 | 0.01 |
Current rhinoconjunctivitis: Age 6–7 years | 9.5 (5.3) | 8.6 (5.0) | 7.0 (3.0) | 0.011 | 0.87 | NS | 2.42 | 0.003 | 1.55 | NS |
Change per year in Current rhinoconjunctivitis: Whole Cohort | 0.11 (0.79) | 0.59 (0.77) | 0.12 (0.57) | 0.006 | −0.48 | 0.005 | −0.01 | NS | 0.47 | 0.002 |
Change per year in Current rhinoconjunctivitis: Age 13–14 years | 0.06 (0.99) | 0.66 (0.86) | 0.09 (0.71) | 0.027 | −0.61 | 0.018 | −0.03 | NS | 0.58 | 0.011 |
Change per year in Current rhinoconjunctivitis: Age 6–7 years | 0.19 (0.29) | 0.41 (0.52) | 0.17 (0.26) | NS | −0.22 | NS | 0.02 | NS | 0.24 | NS |
Current wheeze: Whole cohort | 12.9 (7.5) | 11.6 (6.5) | 12.7 (6.5) | NS | 1.32 | NS | 0.85 | NS | −0.48 | NS |
Current wheeze: Age 13–14 years | 13.0 (6.8) | 11.5 (5.9) | 12.9 (7.2) | NS | 1.53 | NS | 0.05 | NS | −1.48 | NS |
Current wheeze: Age 6–7 years | 12.8 (8.5) | 11.9 (7.6) | 10.8 (4.9) | NS | 0.97 | NS | 2.02 | NS | 1.05 | NS |
Asthma Ever: Whole Cohort | 12.2 (7.7) | 8.9 (5.0) | 11.2 (8.3) | 0.009 | 3.36 | 0.002 | 1.04 | NS | −2.32 | 0.028 |
Asthma Ever: Age 13–14 years | 13.0 (7.1) | 9.8 (5.1) | 12.3 (8.6) | NS | 3.23 | 0.019 | 0.70 | NS | −2.53 | NS |
Asthma Ever: Age 6–7 years | 10.9 (8.4) | 7.4 (4.5) | 9.6 (7.5) | NS | 3.54 | 0.048 | 1.33 | NS | −2.21 | NS |