Table 3.

Imaging site prediction results with CT simulated data.

k	n	External test set	Leaked internal test set	Not leaked internal test set
3	25	0.330 (0.080)	0.253 (0.050)*	0.340 (0.049)
3	50	0.330 (0.052)	0.269 (0.035)*	0.335 (0.034)
3	100	0.347 (0.037)	0.299 (0.033)*	0.347 (0.032)
3	250	0.321 (0.023)	0.288 (0.016)*	0.320 (0.015)
10	25	0.096 (0.026)	0.054 (0.016)*	0.100 (0.020)
10	50	0.098 (0.019)	0.072 (0.012)*	0.108 (0.013)
10	100	0.096 (0.013)	0.071 (0.007)*	0.097 (0.007)
10	250	0.100 (0.008)	0.085 (0.005)*	0.102 (0.005)
36	25	0.025 (0.007)	0.010 (0.002)*	0.027 (0.004)
36	50	0.027 (0.005)	0.014 (0.002)*	0.027 (0.002)
36	100	0.028 (0.004)	0.018 (0.001)*	0.029 (0.002)
36	250	0.027 (0.002)	0.021 (0.001)*	0.028 (0.001)

Average balanced accuracy (standard deviation) obtained in the external and internal test sets.

k is the number of single-center datasets, each one containing n participants. CT: cortical thickness.

*One-tailed paired t-test Bonferroni adjusted p-value < 10⁻⁹ for the comparison with the external test set average balanced accuracy.