For the Moving Sound RCT (Publication I), Figure 5 shows the proportion of LPA and MVPA at the baseline, during the first intervention week, and during the final intervention week. Further, Table 6 lists the differences between the groups in accelerometer-measured data at baseline. It also lists the changes within and between the groups in the proportion of LPA and MVPA.
During the baseline week, children in the intervention group had, on average, 5 hours 26 minutes per day Total PA (i.e., PA at any intensity), and the corresponding value in the control group was 5 h 30 min. In the intervention group, time for LPA was, on average, 3 h 3 min and MVPA 2 h 23 min. The control group's corresponding values were 3 h 4 min for LPA and 2 h 26 min for MVPA. The proportions of the measurement time were 23% for LPA and 18%
for MVPA, separately, in both groups. At the baseline, the proportions of LPA and MVPA were slightly lower in the intervention group than in the control group. The differences between the groups were not significant either in the unadjusted or adjusted model.
The proportion of LPA tended to decrease in both groups and among children in the control group change in time showed a statistically significant
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difference over time both in the unadjusted (est. -0.015, 95% CI -0.026 to -0.003, p = 0.015) and adjusted (est. -0.015, 95% CI -0.027 to -0.002, p = 0.019) model.
Regarding the children in the intervention group, significance was narrowly missed both in the unadjusted (est. 0.011, 95% CI -0.023 to 0.001, p = 0.065) and adjusted (est. -0.011, 95% CI -0.024 to 0.001, p = 0.064) model. Over time, the proportion of MVPA tended to increase in the intervention group and to decrease in the control group, but the changes within groups were not significant. The changes in time between the groups was not significant either in LPA or MVPA in the unadjusted or adjusted model.
Based on the diaries, only ten children in the intervention group were reported to use the movement-to-music video program during the final intervention week. Sensitivity analysis for these children (n = 10) and those who belonged to the control group (n = 91) showed statistically significant reduction in LPA among children in the control group both in the unadjusted (est. -0.015, 95% CI -0.027 to -0.003, p = 0.018) and adjusted (est. -0.015, 95% CI -0.027 to -0.002, p = 0.020) model over time. No other differences within or between groups were found.
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FIGURE 5 Scatter plots of light and moderate-to-vigorous physical activity per day and trends of change over time in the Moving Sound RCT. Black lined circles de-note the observed proportion of light and moderate-to-vigorous physical ac-tivity per day among the intervention group, and gray lined circles among the control group. The solid black line shows an estimated direction of change for the intervention and the grey dotted line for the control group.
5 10 15 20 25 30 35 40
0 10 20 30 40 50 60 70 80
The proportion of light physical activity
%
Time in days
○Intervention group (obs.) ―Intervention group (est.)
○Control group (obs.) - -Control group (est.)
5 10 15 20 25 30 35 40
0 10 20 30 40 50 60 70 80
The proportion of moderate-to-vigorous physical activity
%
Time in days
○Intervention group (obs.) ―Intervention group (est.)
○Control group (obs.) - -Control group (est.)
TABLE 6 Change within and between the groups in light and moderate-to-vigorous physical activity over time as a proportion of measurement time (estimates, 95% confidence intervals (CI), and p-value) in the Moving Sound RCT
Unadjusted (n = 180) Adjusted* (n = 170)
estimate (95% CI) p-value estimate (95% CI) p-value
Light physical activity**
difference at baseline (ref. = control) -0.090 (-1.084 to 0.903) 0.86 -0.117 (-1.138 to 0.904) 0.82 change in time, control -0.015 (-0.026 to -0.003) 0.015 -0.015 (-0.027 to -0.002) 0.019 change in time, intervention -0.011 (-0.023 to 0.001) 0.065 -0.011 (-0.024 to 0.001) 0.064 intervention effect (ref. = control) 0.003 (-0.014 to 0.020) 0.71 0.003 (-0.014 to 0.020) 0.72 Moderate-to-vigorous physical activity**
difference at baseline (ref. = control) -0.128 (-1.289 to 1.034) 0.83 -0.140 (-1.315 to 1.035) 0.81 change in time, control -0.003 (-0.018 to 0.012) 0.71 -0.004 (-0.019 to 0.012) 0.62 change in time, intervention 0.003 (-0.013 to 0.018) 0.73 0.002 (-0.013 to 0.018) 0.75 intervention effect (ref. = control) 0.005 (-0.016 to 0.027) 0.61 0.006 (-0.016 to 0.028) 0.57
* Adjusted for child’s BMI-for-age, daycare or preschool (yes/no), and number of siblings
** The proportion of measurement time
Bold values denote statistical significance at the p < 0.05 level.
BMI-for-age = body mass index (kg/m2), based on measured weight and height, and transmitted to adult scale, ref. = reference group
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For the Step into Music! -study (Publication IV), Figure 6 shows the proportion of LPA, MVPA, and Total PA at the baseline week, for the first intervention week, and the final intervention week.
During the baseline week, children had, on average, 5 h 9 min per day Total PA. Time for LPA was, on average, 2 h 47 min and that for MVPA 2 h 22 min (the proportion of measurement time being 22% for LPA and 19% for MVPA). The proportion of LPA and MVPA tended to increase during the intervention, but the change over time was not statistically significant (LPA: est.
0.007, 95% CI -0.02 to 0.04, p = 0.62; MVPA: est. 0.0003, 95% CI -0.06 to 0.05, p = 0.99). Further, the proportion of Total PA seemed to increase, but the change over time was not statistically significant either (est. 0.006, 95% CI -0.05 to 0.06, p = 0.81).
A sensitivity analysis for children who used the mat as instructed (n = 5) showed a reduction in SB (estimate -0.03, 95% CI -0.18 to 0.13, p = 0.67), SS (-0.17, -0.42 to 0.07, p = 0.16) and LPA (-0.01, -0.11 to 0.08, p = 0.65) and an increase in MVPA (0.10, -0.23 to 0.44, p = 0.39) and Total PA (0.06, -0.24 to 0.35, p = 0.52).
These changes were not statistically significant, but when expressed as minutes per day, children who used the mat as instructed had, on average, 44 minutes less SB per day and 16 min/d more Total PA during the final intervention week as compared to their baseline week. However, it needs to be noted that when expressed as minutes per day, the average measurement time during the baseline week was around 20 min longer per day than during the final intervention week.
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FIGURE 6 Scatter plots of light, moderate-to-vigorous, and total physical activity per day and trends of changes over time in the Step into Music! -study. Black lined circles denote the observed proportion of light and moderate-to-vigorous physical activity per day. The solid black line shows an estimated direction of change for the study group.
5 10 15 20 25 30 35 40
0 10 20 30 40 50 60 70 80
The proportion of light physical activity
%
Time in days
5 10 15 20 25 30 35 40
0 10 20 30 40 50 60 70 80
The proportion of moderate-to-vigorous physical activity
%
Time in days
0 10 20 30 40 50 60 70
0 10 20 30 40 50 60 70 80
The proportion of total physical activity
%
Time in days
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5.5 The effect of parents’ sedentary behavior and physical