Table 2. The effect sizes (Cohen’s d statistic) for inter-class comparisons in males and females. Age Classification Comparison 20-24 vs. 25-29 25-29 vs. 30-34 30-34 vs. 35-39 35-39 vs. 40-44 40-44 vs. 45-49 45-49 vs. 50-54 50-54 vs. 55-59 55-59 vs. 60-64 60-64 vs. 65-69 Male 1.6 .5 .6 .5 1.2 .5 1.9 1.6 1.6 Female 1.5 .2 .4 1.0 .8 1.0 1.2 1.7 N/A Large effect size ≥ 0.80, medium effect size ≥ 0.50, small effect size ≥ 0.20. There was insufficient data in the female 65-69 age class preventing analysis. N/A indicates that insufficient data were available.