Table 1.

Cross-classification of nocturnal hypertension on two 24-hour ambulatory blood pressure monitoring (ABPM) recording periods

		Second 24-hour ABPM (ABPM2)		Reproducibility
		Nocturnal hypertension	No nocturnal hypertension	Kappa	95% CI
First 24-hour ABPM (ABPM1)	Nocturnal hypertension	58	18	0.65	0.55–0.76
	No nocturnal hypertension	20	186

The data are expressed as the number of participants, and kappa statistic with 95% CI. Bolded numbers represent the number of participants with concordant results across the 2 ABPM recordings. Nocturnal hypertension is defined as mean sleep systolic/diastolic blood pressure ≥120/70mm Hg.