Table 3.
Test–retest reliability and internal consistency
| Constructs | Baseline NK score (T0) | Follow-up NK score (T1) | Correlation (total scores) | Correlation (individual answers) | Inter-item correlation | Overall Cronbach’s α | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Mean | sd | Mean | sd | r | P-value* | r | P-value* | |||
| 1: experts’ recommendation | 4·0 | 1·2 | 4·2 | 1·3 | 0·600 | <0·001 | 0·557 | <0·001 | 0·025 | 0·12 |
| 2: nutrients contents of food | 34·6 | 6·4 | 34·6 | 6·3 | 0·847 | <0·001 | 0·595 | <0·001 | 0·060 | 0·75 |
| 3: health aspects of food and diet | 6·7 | 1·6 | 7·1 | 1·6 | 0·542 | <0·001 | 0·559 | <0·001 | 0·061 | 0·40 |
| 4: relationship between diet and diseases | 12·3 | 3·1 | 12·7 | 2·8 | 0·648 | <0·001 | 0·588 | <0·001 | 0·145 | 0·72 |
| 5: proper food choice | 3·2 | 1·4 | 3·4 | 1·3 | 0·688 | <0·001 | 0·653 | <0·001 | 0·059 | 0·31 |
| Total | 60·7 | 10·6 | 62·0 | 10·5 | 0·835 | <0·001 | 0·594 | <0·001 | 0·056 | 0·84 |
NK, nutrition knowledge.
*
Pearson’s correlation test with P < 0·05.