Table 3.

Pearson correlation coefficient, P values, 95% CI, and mean bias for the average heart rate (HR) and HR variability parameters per night collected from the Oura Ring and Shimmer3.

Parameter	Pearson correlation coefficient	P value	95% CI	Mean bias
HR	0.99968	<.001	−0.92 to 0.03	−0.44
RMSSDa	0.96210	<.001	−33.29 to 1.53	−15.88 ms
SDNNb	0.88469	<.001	−25.88 to 24.37	−0.76 ms
AVNNc	0.88010	<.001	−153.75 to 133.64	−10.05 ms
pNN50d	0.91251-	<.001	−0.1 to 0.22	0.06
LFe band	0.82916	<.001	−535.08 to 570.17	17.54 ms2
HFf band	0.92585	<.001	−542.39 to 598.06	27.83 ms2
LF:HF ratio	0.69837	<.001	−0.98 to 0.78	−0.1

^aRMSSD: root mean square of successive differences between normal heartbeats.

^bSDNN: SD of normal beat-to-beat intervals.

^cAVNN: average of normal heartbeat intervals.

^dpNN50: percentage of successive beat-to-beat intervals that differ by more than 50 ms.

^eLF: low frequency.

^fHF: high frequency.