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The comparison of z and z* statistics in three age subgroups
| Age <30 | Age 30-39 | Age >=40 | |
|---|---|---|---|
| Means | 12 | 11 | 11 |
| SD | 6.3 | 4.3 | 3.9 |
| n | 233 | 570 | 65 |
| z statistic | 3.1© | 0.6« | 1.7ü |
| z* statistic | 5.5© | 4.9« | 3.3ü |
SD, standard deviation; N, numbers of cases. ©, difference between age <30 and age 30-39. «, difference between age 30-39 and age >=40. ü, difference between age <30 and age >=40
