Table 1.
Demographic characteristics of the study sample at pre-intervention: third and fourth grade children (n 664) from twelve primary schools in North Rhine-Westphalia, Germany, beginning of the 2012/13 school year
| Thrice weekly (total N 183) | Twice weekly (total N 250) | Control (total N 231) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| n | % | n | % | n | % | χ 2 | P value | df | |
| Grade | |||||||||
| 3rd grade | 83 | 45·4 | 127 | 50·8 | 128 | 55·4 | |||
| 4th grade | 100 | 54·6 | 123 | 49·2 | 103 | 44·6 | 4·13 | 0·127 | 2 |
| Gender | |||||||||
| Girl | 100 | 54·6 | 124 | 49·6 | 101 | 43·7 | |||
| Boy | 83 | 45·4 | 126 | 50·4 | 130 | 56·3 | 4·94 | 0·084 | 2 |
| Lunch at home | |||||||||
| Yes | 133 | 72·7 | 136 | 54·4 | 110 | 47·6 | |||
| No | 50 | 27·3 | 114 | 45·6 | 121 | 52·4 | 27·35 | 0·000 | 2 |
| SES* | |||||||||
| Low | 74 | 40·4 | 39 | 15·6 | 19 | 8·2 | |||
| Middle | 52 | 28·4 | 63 | 25·2 | 55 | 23·8 | 84·86 | 0·000 | 4 |
| High | 57 | 31·1 | 148 | 59·2 | 157 | 68·0 | |||
SES, socio-economic status.
*
Brandenburger Social Index of Böhm et al.( 42 ).