TABLE 2.
Derivation set | Test set2 | ||||
---|---|---|---|---|---|
Strata | n | ρ 3 | Strata | n | ρ |
Metabolite score | |||||
Random half 1 | 5382 | 0.47 | Random half 2 | 5424 | 0.43 |
Random half 2 | 5424 | 0.45 | Random half 1 | 5382 | 0.44 |
Pooled4 | 0.43 | ||||
Metabolite score from backwards regression | |||||
Random half 1 | 5382 | 0.45 | Random half 2 | 5424 | 0.42 |
Random half 2 | 5424 | 0.43 | Random half 1 | 5382 | 0.42 |
Pooled | 0.42 | ||||
Metabolite score stratified by age, y | |||||
≤48.5 | 5424 | 0.48 | >48.5 | 5382 | 0.42 |
>48.5 | 5382 | 0.46 | ≤48.5 | 5424 | 0.43 |
Pooled | 0.42 | ||||
Metabolite score stratified by sex | |||||
Men | 5031 | 0.46 | Women | 5775 | 0.40 |
Women | 5775 | 0.43 | Men | 5031 | 0.43 |
Pooled | 0.43 | ||||
Metabolite score stratified by BMI, kg/m2 | |||||
≤26.2 | 5470 | 0.47 | >26.2 | 5336 | 0.37 |
>26.2 | 5336 | 0.40 | ≤26.2 | 5470 | 0.43 |
Pooled | 0.43 | ||||
Metabolite score stratified by smoking status | |||||
Former or current | 4934 | 0.50 | Never | 5874 | 0.42 |
Never or current | 7236 | 0.46 | Former | 3572 | 0.42 |
Never or former | 9446 | 0.44 | Current | 1362 | 0.40 |
Pooled | 0.43 | ||||
Metabolite score stratified by study site5 | |||||
Cambridge and Ely | 7794 | 0.46 | Wisbech | 3012 | 0.38 |
Cambridge and Wisbech | 6817 | 0.48 | Ely | 3989 | 0.40 |
Ely and Wisbech | 7001 | 0.43 | Cambridge | 3805 | 0.41 |
Pooled | 0.42 |
Total n = 10,806. MDS, Mediterranean diet score.
Scoring weights were derived from a derivation set, then applied to independent samples (a test set) within the Fenland Study. Then, the mass Spearman's ρ between the metabolite score and the MDS was calculated in the test set.
ρ represents Spearman's ρ of the metabolite scores with the MDS based on the Mediterranean dietary pyramid within the derivation set (subject to an overfitting problem).
Spearman's ρ between the metabolite score and the MDS was calculated by pooling 2 or 3 independent test sets.
Three study sites of the Fenland Study (Cambridge, Ely, and Wisbech in Cambridgeshire, United Kingdom).