Skip to main content

Table 3 Study 2: Objectively measured physical activity at baseline and follow-up by study condition and total sample

From: Examining the impact of a province-wide physical education policy on secondary students’ physical activity as a natural experiment

  Comparison (Alberta) (n=224) Intervention (Manitoba) (n =447) Total (n = 671)  
Accelerometer data n (%) n (%) n (%) P value
Students with valid MVPA at time point
 T0: Pre-policy 224 (100.0) 447 (100.0) 671 (100.0) N.A.
 T1: February 2009 – June 2009 120 (53.6) 167 (37.4) 287   N.A.
 T2: September 2009 – January 2010 20 (8.9) 94 (21.0) 114 (42.8) N.A.
 T3: February 2010 – June 2010 67 (29.9) 232 (51.9) 299 (17.0) N.A.
 T4 : September 2010 – January 2011 21 (9.4) 54 (12.1) 75 (44.6) N.A.
 T5 : February 2011 – June 2011 0 (0) 124 (27.7) 124 (11.2) N.A.
 T6 : September 2011 – January 2012 14 (6.3) 44 (9.8) 58 (18.5) (8.6) N.A.
Times points contributed/ student, mean ± SD 2.1 0.8 2.6 1.1 2.4 1.0 <.0001*
Baseline MVPA
 Students with baseline data 224 (100.0) 447 (100.0) 671 (100.0) N.A.
 Minutes/day, mean ± SD 53.0 21.9 58.3 24.0 56.5   0.0039
 Accumulated ≥ 30 min/day 194 (86.6) 396 (88.6) 590 23.4  
 Accumulated ≥ 60 min/day 76 (33.9) 199 (44.5) 275 (87.9) (41.0) 0.4571
0.0085
MVPA at students’ last follow-up
 Students with ≥ 1 follow up data 165 (73.7) 340 (76.1) 505 (75.3) 0.4965
 Minutes/day, mean ± SD 49.4 22.2 44.1 23.7 45.8 23.3 0.0143*
 Accumulated ≥ 30 min/day (% with ≥ 1 follow up) 131 (79.4) 231 (67.9) 362 (71.7) 0.0074
 Accumulated ≥ 60 min/day (% with ≥ 1 follow up) 48 (29.1) 71 (20.9) 119 (23.6) 0.0415
MVPA change from baseline to last follow up        
 Change (min/day), mean ± SD -3.7 25.3 -13.4 26.2 -10.3 26.3 <.0001*
 Mean percentage change (%), mean ± SD 14.2 130.5 -15.9 49.6 -6.1 86.0 0.0047*
  1. N.A. denotes not applicable
  2. *Student’s t-test was used to compare across study condition
  3. Chi-square test was used to compare across study condition
  4. P-value = comparison of comparison and intervention cohorts