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Table 2 Linear mixed model estimates of regression parameters

From: Measuring moderate-intensity walking in older adults using the ActiGraph accelerometer

Variable Modela Intercept (95% CI) (MVPA cut point) METs (linear term) (95% CI) METs (quadratic term) (95% CI) BMI (95% CI) Intercept SD (inter-individual variability in MVPA cut point)
VA (counts · min−1) 1 1013 (734, 1292) 1062 (902, 1221) 71 (−51, 193) - 941.3
  2 1015 (763, 1267) 1622 (1435, 1793) 70 (−50, 190) −73 (−128, −18) 845.8
VM (counts · min−1) 1 1924 (1657, 2192) 1665 (1363, 1967) −251 (−450, −51) - 888.6
  2 1931 (1690, 2172) 1656 (1350, 1962) −181.1 (−384, 22) −81 (−140, −22) 793.2
Walking speed (km · hr−1) 1 2.5 (2.2, 2.8) 1.8 (1.6, 1.9) −0.3 (−0.4, −0.2) - 0.9920
  2 2.5 (2.3, 2.8) 1.7 (1.6, 1.9) −0.2 (−0.4, −0.1) 0 (−0.1, 0) 0.8973
  1. aModel 1 = quadratic equation with random slope and intercept with METs (centred at 3 METS) as the predictor, Model 2 = model 1 with the addition of BMI (centred at the mean value, 27.4 kg · m−2) as a covariate
  2. MVPA moderate-to-vigorous intensity physical activity, CI confidence intervals, SD standard deviation, VA vertical axis, VM vector magnitude, BMI body mass index