Crude associations of key variables with motor outcomes*
| Low motor ASQ score | Maximum grip strength (kg) | Minimum run time (s) | Maximum number of squats | |
|---|---|---|---|---|
| N | 560† | 808 | 842 | 821 |
| 25-OH-vitamin D (log ng/mL) | 0.80 (0.25 to 2.49) p=0.69 | 0.005 (−0.23 to 0.24) p=0.96 | −0.27 (−0.59 to 0.05) p=0.10 | −0.52 (−1.21 to 0.17) p=0.14 |
| HAZ | 0.54 (0.38 to 0.78) p=0.001 | 0.03 (−0.04 to 0.09) p=0.42 | −0.34 (−0.42 to −0.25) p<0.001 | −0.04 (−0.24 to 0.16) p=0.72 |
| Height-for-age‡ | ||||
| Z≥−2 | 1 | 0 | 0 | 0 |
| Z<−2 | 2.71 (1.31 to 5.61) p=0.007 | −0.06 (−0.19 to 0.07) p=0.37 | 0.54 (0.37 to 0.72) p<0.001 | 0.04 (−0.34 to 0.42) p=0.85 |
| BMIZ | 0.89 (0.58 to 1.37) p=0.60 | 0.04 (−0.03 to 0.11) p=0.22 | −0.02 (−0.12 to 0.08) p=0.66 | 0.03 (−0.18 to 0.23) p=0.80 |
| BMIZ‡ | ||||
| Z≥−2 | 1 | 0 | 0 | 0 |
| Z<−2 | 1.04 (0.34 to 3.18) p=0.95 | −0.14 (−0.31 to 0.03) p=0.12 | 0.11 (−0.13 to −0.35) p=0.37 | −0.01 (−0.53 to 0.50) p=0.96 |
| Birth weight (tertile) | ||||
| Low <2.15 kg | 1, p=0.16 | 0, p=0.17 | 0, p=0.17 | 0, p=0.91 |
| Middle 2.15 to <2.31 kg | 0.77 (0.36 to 1.66) | −0.07 (−0.22 to 0.09) | −0.16 (−0.31 to 0.06) | −0.10 (−0.57 to 0.37) |
| High ≥2.31 kg | 0.42 (0.17 to 1.02) | 0.08 (−0.08 to 0.23) | −0.20 (−0.41 to 0.02) | −0.06 (−0.52 to 0.40) |
| Length-for-age Z score at 6 months (tertile)§ | ||||
| Low <−2.28 | 1, p=0.01 | 0, p=0.54 | 0, p=0.005 | 0, p=0.51 |
| Middle −2.28 to −1.43 | 1.74 (0.76 to 3.98) | 0.04 (−0.13 to 0.21) | −0.14 (−0.36 to 0.09) | −0.24 (−0.73 to 0.25) |
| High ≥−1.42 | 0.27 (0.07 to 0.99) | 0.09 (−0.07 to 0.26) | −0.37 (−0.59 to −0.14) | 0.006 (−0.48 to 0.49) |
| Length-for-age Z score gain 0–6 months (tertile)§ | ||||
| Low <−0.17 gain | 1, p=0.42 | 0, p=0.60 | 0, p=0.03 | 0, p=0.79 |
| Middle −0.17 to 0.51 gain | 2.06 (0.70 to 6.00) | −0.08 (−0.25 to 0.08) | 0.04 (−0.18 to 0.25) | 0.16 (−0.31 to 0.63) |
| High >0.51 gain | 1.78 (0.60 to 5.28) | −0.04 (−0.20 to 0.13) | −0.24 (−0.46 to −0.01) | 0.11 (−0.38 to 0.60) |
| Radius QUS Z | 0.87 (0.63 to 1.19) p=0.37 | −0.02 (−0.08 to 0.04) p=0.52 | −0.07 (−0.16 to 0.02) p=0.11 | 0.12 (−0.06 to 0.30) p=0.20 |
| Radius QUS Z‡ | ||||
| Z≥0 | 1, p=0.18 | 0, p=0.67 | 0, p=0.07 | 0, p=0.25 |
| 0<Z≥−2 | 2.47 (0.84 to 7.24) | 0.06 (−0.09 to 0.20) | 0.23 (0.03 to 0.43) | −0.24 (−0.67 to 0.18) |
| Z<−2 | 1.30 (0.27 to 6.16) | 0.09 (−0.16 to 0.35) | 0.12 (−0.23 to 0.46) | −0.61 (−1.35 to 0.14) |
| Tibia QUS Z | 1.20 (0.88 to 1.65) p=0.25 | −0.11 (−0.17 to −0.04) p=0.002 | −0.09 (−0.18 to −0.003) p=0.04 | −0.05 (−0.24 to 0.15) p=0.62 |
| Tibia QUS Z‡ | ||||
| Z>=0 | 1, p=0.77 | 0, p=0.004 | 0, p=0.20 | 0, p=0.38 |
| 0<Z≥−2 | 0.79 (0.38 to 1. 64) | 0.19 (0.05 to 0.33) | 0.07 (−0.12 to 0.27) | 0.17 (−0.25 to 0.59) |
| Z<−2 | 0.69 (0.18 to 2.61) | 0.42 (0.14 to 0.70) | 0.34 (−0.03 to 0.71) | −0.31 (−1.10 to 0.48) |
| Sun exposure (h/day) | ||||
| Never | 1, p=0.06 | 0, p=0.52 | 0, p=0.14 | 0, p=0.22 |
| <1 | 0.29 (0.11 to 0.79) | 0.13 (−0.14 to 0.40) | −0.35 (−0.73 to 0.02) | 0.48 (−0.33 to 1.29) |
| 1–2 | 0.29 (0.10 to 0.81) | 0.16 (−0.12 to 0.44) | −0.40 (−0.78 to −0.02) | 0.41 (−0.42 to 1.24) |
| >2 | 0.36 (0.13 to 1.01) | 0.22 (−0.08 to 0.51) | −0.47 (−0.87 to −0.07) | 0.86 (−0.01 to 1.73) |
| Animal food intake score¶ | ||||
| 0 | 1, p=0.90 | 0, p=0.48 | 0, p=0.77 | 0, p=15 |
| 1 | 0.98 (0.38 to 2.54) | 0.10 (−0.07 to 0.28) | −0.09 (−0.32 to 0.15) | −0.40 (−0.91 to 0.10) |
| ≥2 | 0.80 (0.25 to 2.54) | 0.05 (−0.17 to 0.27) | −0.06 (−0.36 to 0.23) | −0.63 (−1.27 to 0.02) |
| SES quintile | ||||
| Lowest | 1, p=0.18 | 0, p=0.64 | 0, p=0.35 | 0, p=0.008 |
| Low | 0.38 (0.12 to 1.18) | −0.18 (−0.42 to 0.07) | −0.05 (−0.38 to 0.28) | 0.72 (0.01 to 1.43) |
| Middle | 0.30 (0.09 to 1.01) | −0.14 (−0.37 to 0.09) | −0.06 (−0.26 to 0.37) | −0.32 (−0.99 to 0.30) |
| High | 0.36 (0.13 to 0.97) | −0.08 (−0.29 to 0.14) | −0.005 (−0.30 to 0.29) | −0.27 (−0.91 to 0.37) |
| Highest | 0.57 (0.23 to 1.44) | −0.12 (−0.33 to 0.10) | −0.19 (−0.48 to 0.10) | −0.27 (−0.90 to 0.37) |
| Recent morbidity—yes | 1.58 (0.80 to 3.10) p=0.19 | −0.07 (−0.20 to 0.07) p=0.31 | 0.30 (0.12 to 0.48) p=0.01 | −0.24 (−0.64 to 0.16) p=0.24 |
Bold typeface indicates significance at p<0.05.
*Values represent linear regression coefficients (grip strength, run time, squats) or ORs of scoring below the age-specific cut-off for ASQ, (95% CI), Wald p value, controlling for child sex, child age at follow-up testing in whole years and categorical season of follow-up testing.
†ASQ test performed only in children <5.5 years.
‡43% of children had HAZ<−2, 16% had BMIZ; for radius QUS 9% had Z<−2, 64% had −2<Z<0, 26% had Z>0; for tibias QUS 7% had Z<−2, 62% had −2<Z <0, 30% had Z>0.
§Sample sizes are reduced to n=411 for low motor ASQ score, n=696 for grip strength, n=727 for run time, n=709 for squats due to missing 6 month growth data.
¶Animal food score is coded 0=none of dairy, eggs, meat, fish at least three times/week, 1=1 of these at least three times/week; 2=2 or more of these groups at least three times/week.
ASQ, Ages and Stages Questionnaire; BMI, body mass index; BMIZ, BMI-for-age Z; HAZ, height-for-age Z; QUS, quantitative ultrasound; SES, socioeconomic status.