Relative validity of a semi-quantitative food frequency questionnaire for Singaporean toddlers aged 15–36 months

BMC Nutrition

Table 5 Coefficients for the calibration of the sqFFQ, as determined by multivariable linear regression analysis

	Constant^a	sqFFQ^b	Age^c	Sex^c	Adjusted R²
Total energy (kJ)	2992.629	0.195	58.556	− 675.849	0.306
protein (g)	13.336	0.252	0.739		0.171
total fat (g)	29.570	0.160	0.390	−5.430	0.150
SFA (g)	12.111	0.182			0.043
MUFA (g)^d	2.508	0.007		−0.137	0.063
PUFA(g)^d	1.871	0.030		−0.157	0.192
DHA (g)^d	0.292	0.031	0.006		0.198
total CHO (g)	91.260	0.190	1.930	−26.010	0.260
sugars (g)^d	3.952	0.005		−0.288	0.225
fibre (g)^d	1.713	0.033		−0.142	0.313
Vitamins
A (μg)^d	10.510	0.001	−0.053	−0.822	0.144
B1 (mg)^d	0.777	0.158
B2 (mg)	0.507	0.457			0.264
B3 (mg)	5.599	0.330			0.156
DFE (μg)	181.225	0.223	3.732	−69.446	0.221
B12 (μg)	0.726	0.583			0.268
C (mg)^d	4.157	0.016		−0.486	0.256
E (mg)^d	1.464	0.029			0.040
Minerals
Ca (mg)^d	7.722	0.002		−0.659	0.388
Fe (mg)^d	1.783	0.034		−0.150	0.331
I (μg)^d	4.602	0.003			0.074
K (mg)	394.551	0.326	19.487		0.202
Mg (mg)^d	4.397	0.003	0.025	−0.333	0.278
P (mg)^d	7.453	0.001	0.047	−0.536	0.285
Na (mg)^d	7.270	0.002			0.212
Zn (mg)^d	1.802	0.024		−0.141	0.193

^aConstant statistically significant (p < 0.05) for all nutrients except protein
^bsqFFQ statistically significant (p < 0.05) for all nutrients except MUFA
^cAge and/or sex were only included in model if p < 0.10; Sex coded 1 for male and 2 for female
^dThe cube root of the WFR value was used for this nutrient. When the coefficients for this nutrient are used in the linear equation to calibrate sqFFQ values, the final value must be cubed to back-transform

ISSN: 2055-0928