| Variable | Grandparents do not live with children | Grandparents live with children | Difference | ||
| Sample size | Mean | Sample size | Mean | ||
| Std_test | 1208 | 0.660 | 1025 | 0.630 | 0.03*** |
| Nation | 1208 | 0.820 | 1025 | 0.810 | 0.0100 |
| Area | 1208 | 0.450 | 1025 | 0.370 | 0.08*** |