Figure 2

Estimated variance component mean values (error bars: 90% prediction intervals) resulting from simulations of six different sampling strategies assessing percentage time above 90°. All six strategies used random sampling from n _s  = 10 subjects, approached for n _d  = 2 days each. Green circles, blue squares and red triangles show within-day, between-days and between-subjects variance, respectively. Unfilled and filled symbols show strategies with t _tot  = 120 minutes and t _tot  = 240 minutes, respectively. Red dashed, blue solid and green dotted lines represent the “true” within-day, between-days and between-subjects variance, respectively, according to the parent data set