Narkiewicz 2000.

Study characteristics
Methods	Randomised controlled trial, double‐blind, cross‐over design
Participants	19 healthy young volunteers (18 men and 1 women) with mean age ± SD of 26 ± 2 years participated in the study
Interventions	Alcohol (1.0 g/kg body weight, diluted in 400 mL of water), or Placebo (400 mL water) Consumed over a 30‐minute period
Outcomes	Lower‐body negative pressure Systolic blood pressure Diastolic blood pressure Mean arterial pressure Heart rate
Notes	None was taking any medications All participants were social drinkers only and had abstained from alcohol for a minimum of 48 hours before the study
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Measurements were obtained by use of a randomized, double‐blind, placebo‐controlled design with 2 experimental sessions, a placebo session and an alcohol session" Comment ‐ method of randomisation was not described
Allocation concealment (selection bias)	Unclear risk	Comment ‐ method of allocation concealment was not described
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"A flavoring (Crystal Light) was added to these solutions to prevent the subjects from distinguishing alcohol from placebo" Comment ‐ blinding of participants was probably done
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"Studies were analyzed by investigators blinded to session (alcohol or placebo)" Comment ‐ blinding of outcome assessors was probably done
Incomplete outcome data (attrition bias) All outcomes	Low risk	"Vasovagal responses or discomfort during LBNP in 5 subjects resulted in completion of studies examining the effects of both alcohol and placebo in only 14 subjects (13 men, 1 woman; mean age, 26±2 years)" Comment ‐ reasons for exclusion of participants were reported and balanced across groups, so missing data should not affect the final analysis
Selective reporting (reporting bias) For systolic blood pressure (SBP)	Low risk	Comment ‐ study authors reported SBP and SEM
Selective reporting (reporting bias) For diastolic blood pressure (DBP)	Low risk	Comment ‐ study authors reported DBP and SEM
Selective reporting (reporting bias) For mean arterial blood pressure (MAP)	Low risk	Comment ‐ study authors reported MAP and SEM
Selective reporting (reporting bias) For heart rate (HR)	Low risk	Comment ‐ study authors reported HR and SEM
Other bias (conflict of interest, industry sponsorship)	Low risk	"Dr. Narkiewicz, a visiting research scientist from the Department of Hypertension and Diabetology, Medical University of Gdansk, Gdansk, Poland, was a recipient of an International Research John E. Fogarty Fellowship (NIH 3F05 TW05200) and a Perkins Memorial Award from the American Physiological Society. Dr. Somers is an Established Investigator of the AHA and a Sleep Academic Awardee of the NIH. Other support includes HL61560 and HL65176 (NIH). We thank Diane Davison, RN, MA, for technical assistance"
Other bias (was the study registered in clinical trials.gov/ was the protocol available?)	High risk	Comment ‐ protocol was not registered and study identifier was not reported