Small for gestational age prevalence, odds ratios (95%CI) by social class, and RII by maternal factors and time, Scotland 1980–2000
| Social class | 1980–1984 | 1985–1989 | 1990–1994 | 1995–2000 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| % | OR | 95%CI | % | OR | 95%CI | % | OR | 95%CI | % | OR | 95%CI | ||
| *p for interaction term. | |||||||||||||
| I | 3.5 | 1 | 3.2 | 1 | 2.4 | 1 | 2.3 | 1 | |||||
| II | 4.1 | 1.16 | (1.07, 1.27) | 3.7 | 1.17 | (1.07, 1.28) | 3.4 | 1.41 | (1.27, 1.56) | 3.1 | 1.35 | (1.21, 1.50) | |
| IIInm | 6.1 | 1.80 | (1.66, 1.96) | 5.1 | 1.63 | (1.49, 1.78) | 4.8 | 2.03 | (1.83, 2.25) | 4.3 | 1.94 | (1.74, 2.15) | |
| IIIm | 6.1 | 1.79 | (1.66, 1.94) | 5.1 | 1.64 | (1.51, 1.79) | 4.6 | 1.95 | (1.76, 2.15) | 4.3 | 1.93 | (1.75, 2.14) | |
| IV | 6.9 | 2.06 | (1.90, 2.23) | 6.2 | 2.00 | (1.83, 2.18) | 5.5 | 2.34 | (2.11, 2.58) | 5.3 | 2.42 | (2.18, 2.68) | |
| V | 7.9 | 2.35 | (2.16, 2.56) | 6.6 | 2.14 | (1.94, 2.35) | 6.0 | 2.53 | (2.28, 2.82) | 5.1 | 2.28 | (2.03, 2.57) | |
| Undetermined | 10.4 | 3.21 | (2.92, 3.53) | 7.5 | 2.46 | (2.24, 2.71) | 6.3 | 2.69 | (2.43, 2.99) | 5.9 | 2.71 | (2.44, 3.00) | |
| Total | 6.0 | 5.2 | 4.7 | 4.3 | |||||||||
| RII | p* | p* | p* | p* | |||||||||
| Overall | 2.41 | (2.29, 2.55) | 2.21 | (2.08, 2.34) | 2.28 | (2.14, 2.42) | 2.49 | (2.34, 2.66) | |||||
| Marital status | <0.001 | <0.001 | <0.001 | <0.001 | |||||||||
| Married | 2.14 | (1.99, 2.30) | 2.08 | (1.94, 2.23) | 2.17 | (2.00, 2.36) | 2.24 | (2.03, 2.48) | |||||
| Single | 1.36 | (1.21, 1.54) | 1.33 | (1.17, 1.50) | 1.39 | (1.24, 1.57) | 1.57 | (1.40, 1.76) | |||||
| Other | 1.47 | (1.19, 1.80) | 1.46 | (1.19, 1.80) | 1.43 | (1.18, 1.72) | 2.19 | (1.87, 2.56) | |||||
| Maternal age | <0.001 | <0.001 | <0.001 | <0.001 | |||||||||
| <20 | 1.39 | (1.18, 1.63) | 1.27 | (1.07, 1.52) | 0.97 | (0.79, 1.19) | 0.98 | (0.77, 1.23) | |||||
| 20–34 | 2.47 | (2.33, 2.63) | 2.18 | (2.04, 2.33) | 2.31 | (2.15, 2.48) | 2.46 | (2.28, 2.65) | |||||
| ⩾35 | 3.39 | (2.73, 4.21) | 3.83 | (3.04, 4.83) | 3.15 | (2.56, 3.88) | 4.01 | (3.54, 4.79) | |||||
| Maternal height | 0.03 | <0.001 | 0.56 | <0.001 | |||||||||
| <155 cm | 1.81 | (1.63, 2.00) | 1.54 | (1.37, 1.73) | 1.95 | (1.70, 2.22) | 1.78 | (1.54, 2.07) | |||||
| 155 cm–164 cm | 2.10 | (1.95, 2.25) | 1.89 | (1.75, 2.05) | 1.96 | (1.80, 2.13) | 2.16 | (1.97, 2.36) | |||||
| >164 cm | 2.37 | (2.08, 2.71) | 2.48 | (2.17, 2.82) | 2.19 | (1.93, 2.49) | 2.72 | (2.41, 3.08) | |||||
| Parity | <0.001 | <0.001 | <0.001 | <0.001 | |||||||||
| 0 | 1.79 | (1.67, 1.93) | 1.54 | (1.43, 1.67) | 1.73 | (1.60, 1.88) | 1.74 | (1.59, 1.90) | |||||
| 1–2 | 2.33 | (2.14, 2.53) | 2.36 | (2.14, 2.60) | 2.40 | (2.17, 2.66) | 3.03 | (2.72, 3.36) | |||||
| 3+ | 2.14 | (1.74, 2.63) | 2.53 | (2.00, 3.20) | 2.40 | (1.86, 3.09) | 3.08 | (2.37, 4.00) | |||||