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. 2016 Nov 4;4(4):e123. doi: 10.2196/mhealth.6469

Table 2.

Correlation and agreement for energy and selected nutrient intake from mean 3-day image-based dietary records in the Diet Bytes and Baby Bumps study (n=25 participants) analyzed by the Selected Nutrient and Diet Quality (SNaQ) tool and FoodWorks (FW) nutrient analysis software.

Nutrient Method Input, median (IQRa) ρ (P value) n (%) <EARb n (%) ≥EAR to <RDIc n (%) ≥RDI Cohen kappa (P value)
Intake from food and supplements





Energy (kJ/day) SNaQ 8418.33 (7755.83-10,004.17) .898 (<.001) N/Ad

.031e (.67)


FW 7738.89 (6329.94-8995.05)





Iron (mg/day) SNaQ 11.30 (8.93-15.08) .812 (<.001) 21(84) 0 (0) 4 (16) .533 (<.001)


FW 13.54 (10.75-21.47)
19 (76) 3 (12) 3 (12)

Calcium (mg/day) SNaQ 877.36 (653.74-1181.60) .791 (<.001) 12 (48) 4 (16) 9 (36) .488 (.001)


FW 831.01 (672.39-1000.89)
13 (52) 6 (24) 6 (24)

Folate, total DFEf (µg/day) SNaQ 851.90 (225.15-1156.15) .893 (<.001) 11 (44) 1 (4) 13 (52) .559 (.001)


FW 820.20 (393.53-1383.00)
8 (32) 2 (8) 15 (60)

Iodine (µg/day) SNaQ 167.00 (93.52-311.28) .955 (<.001) 11 (44) 4 (16) 10 (40) .803 (<.001)


FW 171.42 (92.58-300.20)
12 (48) 3 (12) 10 (40)

Zinc (mg/day) SNaQ 13.09 (10.46-19.56) .905 (<.001) 3 (12) 4 (16) 18 (72) .741 (<.001)


FW 14.66 (10.24-21.24)
3 (12) 5 (20) 17 (68)
Intake from food only, supplements excluded





Energy (kJ/day) SNaQ 8418.33 (7755.83-10,004.17) .898 (.000) N/A

.031e (.67)


FW 7738.89 (6329.94-8995.05)





Iron (mg/day) SNaQ 9.50 (7.70-10.85) .510 (.009) 25 (100) 0 (0) 0 (0) Constants (no statistics computed)


FW 11.78 (8.53, 13.73)
25 (100) 0 (0) 0 (0)

Calcium (mg/day) SNaQ 809.90 (653.75-1181.70) .888 (<.001) 14 (56) 2 (8) 9 (36) .554 (<.001)


FW 736.61 (663.19-927.37)
17 (68) 3 (12) 5 (20)

Folate, total DFE (µg/day) SNaQ 319.00 (240.25-433.35) .600 (.002) 21 (84) 4 (16) 0 (0) -.068 (.52)


FW 409.79 (259.74-642.22)
16 (64) 2 (8) 7 (28)

Iodine (µg/day) SNaQ 99.00 (79.80-139.05) .850 (<.001) 22 (88) 2 (8) 1 (4) .632 (<.001)


FW 104.25 (86.46-130.95)
22 (88) 2 (8) 1 (4)

Zinc (mg/day) SNaQ 10.60 (8.40-13.10) .745 (<.001) 7 (28) 6 (24) 12 (48) .572 (<.001)


FW 10.63 (8.89-13.47)
6 (24) 9 (36) 10 (40)

aIQR: interquartile range (25th-75th percentiles).

bEAR: estimated average requirement. EAR is a nutrient level estimated to meet the requirements of 50% of the healthy individuals in a life stage or gender group, per day (EARs for nutrients as follows: iron 22 mg, calcium 840 mg, folate 520 µg, iodine 160 µg, zinc 9 mg) [10].

cRDI: recommended dietary intake. RDI is the average dietary intake level sufficient to meet nutrient requirements of 97% to 98% of healthy individuals in a life stage or gender group, per day (RDIs for nutrients as follows: iron 27 mg, calcium 1000 mg, folate 600 µg, iodine 220 µg, zinc 11 mg) [10].

dN/A: not applicable.

eKappa for energy intake in categories of 1000 kJ.

fDFE: dietary folate equivalents.