Table 1. Averages of intelligence and psychosocial functioning across levels of socioeconomic status.
| IQ | PF | ||
| No. of men | Mean (SD) | Mean (SD) | |
| 42192 | 5.43 (2.04)a | 5.10 (1.94)b | |
| Years in education | |||
| ≥15 | 6944 | 7.15 (1.47) | 5.77 (1.98) |
| 14 | 5283 | 6.50 (1.61) | 5.62 (1.91) |
| 12–13 | 7140 | 6.02 (1.76) | 5.43 (1.81) |
| 10–11 | 12227 | 4.83 (1.76) | 4.84 (1.86) |
| ≤9 | 10598 | 4.05 (1.79) | 4.47 (1.85) |
| ρ = 0.55***/ρadj = 0.52*** | ρ = 0.25***/ρadj = 0.10*** | ||
| Occupational class | |||
| NMH | 8081 | 6.90 (1.55) | 5.81 (1.92) |
| NMI | 9209 | 6.23 (1.73) | 5.51 (1.86) |
| NML | 4602 | 5.47 (1.83) | 5.20 (1.95) |
| SMW | 10481 | 4.61 (1.80) | 4.77 (1.80) |
| UMW | 9819 | 4.32 (1.95) | 4.42 (1.88) |
| ρ = 0.48***/ρadj = 0.44*** | ρ = 0.26***/ρadj = 0.14*** | ||
| Income quintiles | |||
| 5th | 8961 | 6.70 (1.67) | 5.91 (1.86) |
| 4th | 9088 | 5.71 (1.87) | 5.36 (1.83) |
| 3rd | 9043 | 5.10 (1.91) | 5.00 (1.82) |
| 2nd | 8912 | 4.67 (1.97) | 4.63 (1.86) |
| 1st | 6188 | 4.73 (2.10) | 4.37 (2.00) |
| ρ = 0.35***/ρadj = 0.30*** | ρ = 0.27***/ρadj = 0.18*** | ||
| IQxPF | ρ = 0.30*** |
ρ = Spearman's correlation coefficient; ρadj = partial Spearman's, i.e. adjusted for PF/IQ; *** = p<0.001; NMH = Non-manual workers, higher level; NMI = Non-manual workers, intermediate level; NML = Non-manual workers, lower level; SMW = Skilled manual workers; UMW = Unskilled manual workers; a Skewness = −0.191 (p<0.001); b Skewness = −0.073 (p<0.001). Mean and standard deviation (SD) of intelligence (IQ) and psychosocial functioning (PF) across levels of SES indicators;