Table 2.

Reasons for missing toddler ankle accelerometer data (n = 277)

Category	Specific reasons	N (%)
Valid data	--	191 (69.0 %)
Refusal	Refused to participate in physical activity assessment	38 (13.7 %)
Participant noncompliance	Lost or did not return the accelerometer	3 (1.1 %)
	Wore accelerometer for less than two daysa	30 (10.8 %)
Technical problems	Staff training (i.e.: improper programming and documentation)	11 (3.9 %)
	Device malfunction	4 (1.5 %)

^abecause the first and last days are truncated, if the participant wore the accelerometer for two or fewer days the data were not used