TABLE 3.

Comparison the results of our study and prior researches.

Research	HR	RR	HF	LF	Adverse effects
Gao X.Y.	Acupressure stimulation of the vagus nerve in the ear causes a reduction in heart rate			LF increased in both periods of acupoint stimulation with electromagnetism (electric vibrating pen) and vibration of needles, which differs from our study using pressure on seeds (less strong physical stimulation)
Boehmer A.A.
Buschman H.P.	The timing of stimulation does not affect the amount of cardiac slowing
Kuehl L.K.		The respiratory rate must be considered to ensure a thorough interpretation of frequency-domain indices	Reduced HRV indicates a risk of cardiac and all-cause mortality; low HF is often correlated with stress status and anxiety disorders, whereas increased HF and HRV are related to wellbeing
Laborde S.
Tran N.		Left ear stimulation increased RSA and significantly increased HF
Haker E.		The measuring HF and LF method was calculated appropriately to control the respiratory system’s impact on these indices	An increase in HF and no change in LF during auricular acupuncture in the left Lung acupoint
Clancy A.J.				Performing vagus nerve acupuncture and acupressure in the ear showed no change in LF
Boehmer A.A.
Caetano J.	Heart rate decreases will lead to a significant decrease in both cardiovascular-related and all-cause mortality
Khan H.
Clancy A.J.					No undesirable events when vagus nerve stimulation
Roger A.S.
Our study	Heart rate markedly declined during and after acupressure at the left Sympathetic acupoint in healthy volunteers, and stages with stimulation caused a more significant decrease than without stimulation. No resonance to increase an effect or saturation to decrease such impact in subsequent stimuli	Respiratory rate while evaluating HRV showed no significant change, thus excluding the effect of the respiratory system on HF	HF increased statistically significantly when performing acupressure	No statistically significant differences in LF among study periods in both groups	No undesirable events

Almost our results are similar to the prior research, except for the study of Gao X.Y. in which the LF increased when acupoint stimulation using an electric vibrating pen and vibration of needles. Differences with other research may be due to the difference in the action method, and the discussion of this part was in detail.