Introduction
Empirical Research on Birth Intervals and Health
Birth Intervals and Long-Term Health: Potential Explanatory Mechanisms
Physiological Mechanisms
Social and Environmental Mechanisms
Selection and Confounding
Data and Methods
Data
Outcome Variables
Height
Physical Fitness
BMI Categories
Mortality
Covariates
Statistical Analyses
Military Conscription Data
Mortality Data
Results
Descriptive Statistics
Conscription Sample | Mortality Sample | |||||||
---|---|---|---|---|---|---|---|---|
Preceding | Subsequent | Preceding | Subsequent | |||||
Between | Within | Between | Within | Between | Within | Between | Within | |
Mean | 42.6 | 42.6 | 47.5 | 47.5 | 41.5 | 41.5 | 43.6 | 43.6 |
SD | 22.3 | 11.8 | 26.4 | 16.9 | 19.7 | 20.0 | 23.4 | 21.7 |
Physical Fitness (watts) | Height (cm) | |||||||
---|---|---|---|---|---|---|---|---|
Preceding | Subsequent | Preceding | Subsequent | |||||
Interval | Mean | SD | Mean | SD | Mean | SD | Mean | SD |
9–12 | 295.1 | 50.4 | 294.4 | 52.7 | 178.8 | 6.6 | 178.6 | 6.6 |
13–18 | 297.0 | 51.7 | 298.5 | 52.6 | 179.3 | 6.5 | 179.4 | 6.6 |
19–24 | 299.6 | 52.1 | 301.7 | 51.2 | 179.5 | 6.5 | 179.8 | 6.5 |
25–30 | 301.4 | 51.4 | 302.2 | 51.3 | 179.5 | 6.4 | 179.6 | 6.5 |
31–36 | 300.9 | 51.3 | 302.3 | 51.4 | 179.5 | 6.5 | 179.6 | 6.5 |
37–42 | 299.9 | 50.7 | 301.5 | 51.3 | 179.5 | 6.5 | 179.5 | 6.5 |
43–48 | 299.0 | 51.1 | 302.4 | 51.2 | 179.5 | 6.4 | 179.6 | 6.5 |
49–54 | 299.1 | 51.6 | 301.4 | 50.8 | 179.6 | 6.5 | 179.5 | 6.4 |
55–60 | 298.3 | 50.4 | 299.8 | 51.0 | 179.5 | 6.5 | 179.5 | 6.5 |
61–66 | 298.6 | 50.1 | 301.5 | 52.0 | 179.5 | 6.4 | 179.4 | 6.5 |
67–72 | 298.9 | 52.0 | 300.8 | 50.9 | 179.7 | 6.6 | 179.4 | 6.5 |
73–78 | 299.1 | 50.8 | 302.3 | 50.7 | 179.6 | 6.6 | 179.4 | 6.5 |
79–84 | 298.1 | 51.6 | 301.5 | 52.5 | 179.4 | 6.7 | 179.3 | 6.6 |
85–90 | 297.8 | 49.0 | 299.5 | 51.6 | 179.6 | 6.2 | 179.5 | 6.5 |
91–96 | 299.4 | 49.9 | 299.4 | 49.1 | 179.9 | 6.5 | 179.1 | 6.5 |
97+ | 297.5 | 51.6 | 299.7 | 50.5 | 179.5 | 6.5 | 179.3 | 6.4 |
Total | 299.4 | 51.3 | 301.2 | 51.3 | 179.5 | 6.5 | 179.5 | 6.5 |
Underweight | Overweight | Mortality | ||||||
Preceding | Subsequent | Preceding | Subsequent | Preceding | Subsequent | |||
Interval | % | % | % | % | Rate (10–3) | Deaths | Rate (10–3) | Deaths |
9–12 | 6.4 | 6.8 | 9.5 | 11.7 | 1.22 | 659 | 1.25 | 624 |
13–18 | 7.5 | 7.2 | 10.2 | 10.9 | 1.20 | 6,322 | 1.32 | 6,352 |
19–24 | 6.5 | 7.3 | 9.9 | 10.3 | 1.18 | 7,366 | 1.37 | 7,658 |
25–30 | 6.8 | 7.1 | 9.8 | 10.8 | 1.25 | 6,230 | 1.41 | 6,287 |
31–36 | 6.9 | 7.1 | 11.0 | 10.5 | 1.23 | 5,038 | 1.46 | 5,374 |
37–42 | 7.1 | 7.3 | 11.0 | 10.9 | 1.24 | 3,982 | 1.49 | 4,337 |
43–48 | 6.4 | 7.3 | 11.3 | 10.8 | 1.21 | 3,269 | 1.56 | 3,758 |
49–54 | 7.3 | 7.0 | 11.5 | 11.2 | 1.22 | 2,586 | 1.52 | 2,943 |
55–60 | 6.7 | 7.0 | 13.0 | 10.7 | 1.12 | 2,041 | 1.60 | 2,606 |
61–66 | 5.9 | 6.8 | 13.2 | 10.8 | 1.16 | 1,659 | 1.61 | 2,125 |
67–72 | 7.3 | 6.7 | 13.9 | 10.3 | 1.16 | 1,349 | 1.59 | 1,689 |
73–78 | 7.9 | 6.1 | 14.1 | 11.4 | 1.09 | 1,026 | 1.58 | 1,398 |
79–84 | 6.7 | 6.6 | 15.3 | 10.4 | 1.06 | 822 | 1.64 | 1,215 |
85–90 | 6.1 | 7.4 | 15.4 | 11.3 | 1.00 | 596 | 1.66 | 980 |
91–96 | 4.5 | 6.5 | 17.1 | 10.8 | 0.95 | 477 | 1.63 | 843 |
97+ | 6.0 | 6.3 | 18.0 | 11.1 | 0.84 | 1,635 | 1.68 | 3,820 |
Total | 6.8 | 7.0 | 11.5 | 10.8 | 1.18 | 45,057 | 1.47 | 52,009 |