Additional file 1: Appendix Figure S1. The development of motor lead in years in boys and girls from T1 to T2 for the four different cohorts and from T1-T2-T3 for the two follow-up cohorts (control cohort 1, lockdown cohort 1). Two-year follow-up is done in only 7 schools, which accounts for the differences observed between the samples. Appendix Figure 2. The development of motor lead in years in the four motor ability groups (quartiles) from T1 to T2 for the four different cohorts and from T1-T2-T3 for the two follow-up cohorts (control cohort 1, lockdown cohort 1). Two-year follow-up is done in only 7 schools, which accounts for the differences observed between the samples. Appendix Table 1. Multiple Comparisons with Bonferroni correction between the four cohorts on the difference between motor lead on T1 and T2. Appendix Table 2. Analysis on the role of sex in the difference in motor lead (in years) development from T1 and T2 between the 4 cohorts. Appendix Table 3. Analysis on the role of SES in the ...