Relative validity of the Chrono-Nutrition Behavior Questionnaire (CNBQ) against 11-day event-based ecological momentary assessment diaries of eating

Table 4 Social and eating jetlag variables and chronotype ^a

	CNBQ		EMA food diaries ^b		Paired	Mean	Limit of	Spearman
	n	Mean (SD)	n	Mean (SD)	n	difference ^c	Agreement ^d	correlation ^e
Social jetlag (hours; decimal)	1050	0.92 (1.63)	1050	0.96 (1.18)	1050	− 0.04	− 2.68, 2.60	0.41
Eating jetlag based on eating midpoint 1 (hours;decimal) ^f	1050	0.89 (1.01)	1050	0.77 (0.73)	1050	0.12****	− 1.74, 1.99	0.34
Eating jetlag based on breakfast timing (hours;decimal)	759	1.17 (1.04)	916	1.14 (0.91)	753	0.10**	− 1.73, 1.92	0.57
Eating jetlag based on lunch timing (hours; decimal)	994	0.67 (0.73)	1036	0.64 (0.58)	989	0.05*	− 1.36, 1.46	0.30
Eating jetlag based on dinner timing (hours; decimal)	1033	0.80 (0.89)	1048	0.77 (0.74)	1033	0.04	− 1.55, 1.62	0.39
Chronotype (clock time; decimal)	1050	3.31 (1.54)	1050	3.53 (1.33)	1050	− 0.22****	− 2.97, 2.52	0.71
Chronotype (clock time; decimal) among non- users of clock alarm on non-workdays	659	3.31 (1.28)	659	3.59 (1.36)	659	− 0.28****	− 2.39, 1.83	0.71

CNBQ Chrono-Nutrition Behavior Questionnaire, EMA ecological momentary assessment, SD standard deviation
^a Meals included breakfast, lunch, and dinner. All variables are shown in decimal format, with the unit of hours; decimal (e.g., 0.92 means a duration of 0 h 55 min) or clock time; decimal (e.g., 3.31 means 3:19 AM)
^b Based on 11 days’ data: 2–9 workdays’ data (median 7 days) and 2–9 non-workdays’ data (median 4 days)
^c Calculated as the CNBQ-based value minus the EMA food diary-based value (at the individual level). Paired comparison was made using the paired t-test: * P < 0.05, ** P < 0.01, *** P < 0.001, and **** P < 0.0001
^d Calculated as mean difference plus-minus 1.96 SD of the difference
^e All values were significant (P < 0.0001)
^f Calculated using the start time of first eating occasion and the start time of last eating occasion

ISSN: 1479-5868