ABSTRACT
Whether to select one-tailed test or two-tailed test,how to establish null hypothesis and alternative hypothesis,how to improve the test efficacy were elaborated,and the common problems encountered when hypothesis was applied in scientific papers were pointed out with examples.
ABSTRACT
Objective To investigate the effects of 3％ and 7.5％ hypertonic saline (HS) on hemorrhagic shock patients in Emergency Department.Methods From December 2008 to February 2012,patients older than 15 years with severe trauma and systolic blood pressure (SBP) ≤70 mmHg or 70 to 90 mmHg with heart rate≥ 108 per minute were divided into three groups randomly (random number).Group A:patients treated with 3％ hypertonic saline (HS) 300 mL + lactated Ringer' s solutions (LRS).Group B:patients treated with 7.5％ HS 300 mL + LRS.Group C:patients treated with LRS.The mean arterial pressure (MAP),blood pressure (BP),heart rate (HR) were recorded before infusion and at 10,30,45,60 minutes successively after infusion.Incidence of complications and mortality rates were compared between groups.Results Atotal of 148 patients were enrolled in this study.Compared with LRS grouop,MAP was restored more promptly and maintained persistently in 3％ HS group and 7.5％ HS group,and the total volume of fluid infused was decreased to almost 50％ of LRS in the first 1 hour.No significant differences in MAP levels were observed between group A and B except 30 minutes after infusion.Single bolus of 7.5％ HS infusion resulted in increased of HR to mean 127 beats per minute at 10 minutesafter fluid resuscitation.Higher incidence of arrhythmia and transient hypotension occurred in 7.5％ HS group.There were no statistical differences of changes of electrolytic indices,mortality rates,incidences of ARDS and MODS among three groups.Conclusions Resuscitation with 3％ HS provide similar benefits and lower risk of complications compared with 7.5％ HS and LRS.This study demonstrates the practicability and safety of 3％ HS for fluid resuscitation of patients with hypovolemic shock.
ABSTRACT
Objective To formulate genuine case mix plans using medical record information available in China. Methods An account was given of the research background of case mix studies, the current status of the studies and applications at home and abroad, the case mix model for measuring medical "output", data sources and statistical methods of classification. Results Case mix plans for army inpatients, civilian inpatients and outpatients were respectively formulated, and software for calculating the case mix index of a hospital which can run on Windows 95/98 computer systems was developed. Conclusion The theoretical, methodological and data conditions necessary for the formulation of case mix plans based on the first pages of medical records in China are now ripe and the case mix plans formulated on the basis of data from large samples can now be used for the control of medical costs, the assessment of a hospital's medical "output" and the estimation of the financial compensations for hospitals.