Preference Index |
Cronbach Alpha |
Test-Retest (n=36) |
Numbers of items and subjects |
α
All items |
α, 1 item deleted1 |
Number of items2 |
ICC3 |
r-values3 |
Vegetables |
16, 88 |
0.79 |
0.79 |
12-16 |
0.80 |
0.80 |
Snacks |
18, 90 |
0.87 |
0.89 |
14-18 |
0.80 |
0.80 |
Beverages |
19, 95 |
0.78 |
0.79 |
15-19 |
0.71 |
0.71 |
Dairy Foods |
13, 98 |
0.79 |
0.80 |
10-13 |
0.65 |
0.66 |
Grains and Cereals |
10, 99 |
0.78 |
0.78 |
08-10 |
0.61 |
0.60 |
Not Sweetened Foods |
45, 74 |
0.91 |
0.91 |
38-45 |
0.74 |
0.75 |
Sweetened Foods |
24, 94 |
0.91 |
0.91 |
18-24 |
0.75 |
0.75 |
Sweetened Snacks |
11, 100 |
0.87 |
0.87 |
09-11 |
0.79 |
0.79 |
Sweetened Beverages |
11, 99 |
0.80 |
0.80 |
09-11 |
0.62 |
0.61 |
1Alphas shown following deletion of the single item least related to the other items in the index.
2Scores for indices were calculated for all participants with valid responses for at least 75% of the items included in each index. The numbers of items required for inclusion
in each index are provided.
3ICC=Intraclass correlation coefficient; r-values = Pearson correlation coefficients.
Table 2: Reliability – Cronbach |