This study explores whether the current external quality assessment(EQA)level and acceptable bias for basic semen analysis in China are clinically useful.We collected data of semen EQA from Andrology laboratories in t...This study explores whether the current external quality assessment(EQA)level and acceptable bias for basic semen analysis in China are clinically useful.We collected data of semen EQA from Andrology laboratories in the Hunan Province(China)in 2022 and searched for data in the published literature from January2000 to December 2023 in China.On the basis of these data,we analyzed the coefficients of variation and acceptable biases of different quality control materials for basic semen analysis through robust statistics.We compared these findings with quality specifications based on biological variation from optimal,desirable,and minimum levels of bias to seek a unified and more suitable semen EQAbias evaluation standard for China's national conditions.Different sources of semen quality control material exhibited considerable variation in acceptable biases among laboratories,ranging from 8.2%to 56.9%.A total of 50.0% of the laboratories met the minimum quality specifications for progressive motility(PR),whereas 100.0%and 75.0%of laboratories met only the minimum quality specifications for sperm concentration and total motility(nonprogressive[NP]+PR),respectively.The Z value for sperm concentration and PR+NP was equivalent to the desirable performance specification,whereas the Z value for PR was equivalent only to the minimum performance specification.This study highlights the feasibility of operating external quality assessment schemes for basic semen analysis using quality specifications based on biological variation.These specifications should be unified among external quality control(EQC)centers based on biological variation.展开更多
Variability in the blood-breath ratio(BBR)of alcohol is important,because it relates a mea-surement of the blood-alcohol concentration(BAC)with the co-existing breath-alcohol con-centration(BrAC).The BBR is also used ...Variability in the blood-breath ratio(BBR)of alcohol is important,because it relates a mea-surement of the blood-alcohol concentration(BAC)with the co-existing breath-alcohol con-centration(BrAC).The BBR is also used to establish the statutory BrAC limit for driving from the existing statutory BAC limits in different countries.The in-vivo BBR depends on a host of analytical,sampling and physiological factors,including subject demographics,time after end of drinking(rising or falling BAC),the nature of the blood draw(whether venous or arterial)and the subject's breathing pattern prior to exhalation into the breath analyzer.The results from a controlled drinking study involving healthy volunteers(85 men and 15 women)from three ethnic groups(Caucasians,Hispanics and African Americans)were used to evaluate various factors influencing the BBR.Ethanol in breath was determined with a quantitative infrared analyzer(Intoxilyzer 8000)and BAC was determined by headspace gas chromatography(HS-GC).The BAC and BrAC were highly correlated(r = 0.948)and the BBR in the post-absorptive state was 2 382±119(mean ± SD).The BBR did not depend on gen-der(female:2 396±101 and male:2 380±123,P>0.05)nor on racial group(Caucasians 2 398±124,African Americans 2 344±119 and Hispanics 2 364±104,P>0.05).The BBR was lower in subjects with higher breath-and body-temperatures(P<0.05)and it also decreased with longer exhalation times into the breath-analyzer(P<0.001).In the post-absorptive state,none of the 100 subjects had a BBR of less than 2 100∶1.展开更多
基金supported by the Hunan Province Municipal Natural Science Foundation(2022JJ30018)the Hunan Province Health Commission Science Foundation(B202301037899)to WNL。
文摘This study explores whether the current external quality assessment(EQA)level and acceptable bias for basic semen analysis in China are clinically useful.We collected data of semen EQA from Andrology laboratories in the Hunan Province(China)in 2022 and searched for data in the published literature from January2000 to December 2023 in China.On the basis of these data,we analyzed the coefficients of variation and acceptable biases of different quality control materials for basic semen analysis through robust statistics.We compared these findings with quality specifications based on biological variation from optimal,desirable,and minimum levels of bias to seek a unified and more suitable semen EQAbias evaluation standard for China's national conditions.Different sources of semen quality control material exhibited considerable variation in acceptable biases among laboratories,ranging from 8.2%to 56.9%.A total of 50.0% of the laboratories met the minimum quality specifications for progressive motility(PR),whereas 100.0%and 75.0%of laboratories met only the minimum quality specifications for sperm concentration and total motility(nonprogressive[NP]+PR),respectively.The Z value for sperm concentration and PR+NP was equivalent to the desirable performance specification,whereas the Z value for PR was equivalent only to the minimum performance specification.This study highlights the feasibility of operating external quality assessment schemes for basic semen analysis using quality specifications based on biological variation.These specifications should be unified among external quality control(EQC)centers based on biological variation.
文摘Variability in the blood-breath ratio(BBR)of alcohol is important,because it relates a mea-surement of the blood-alcohol concentration(BAC)with the co-existing breath-alcohol con-centration(BrAC).The BBR is also used to establish the statutory BrAC limit for driving from the existing statutory BAC limits in different countries.The in-vivo BBR depends on a host of analytical,sampling and physiological factors,including subject demographics,time after end of drinking(rising or falling BAC),the nature of the blood draw(whether venous or arterial)and the subject's breathing pattern prior to exhalation into the breath analyzer.The results from a controlled drinking study involving healthy volunteers(85 men and 15 women)from three ethnic groups(Caucasians,Hispanics and African Americans)were used to evaluate various factors influencing the BBR.Ethanol in breath was determined with a quantitative infrared analyzer(Intoxilyzer 8000)and BAC was determined by headspace gas chromatography(HS-GC).The BAC and BrAC were highly correlated(r = 0.948)and the BBR in the post-absorptive state was 2 382±119(mean ± SD).The BBR did not depend on gen-der(female:2 396±101 and male:2 380±123,P>0.05)nor on racial group(Caucasians 2 398±124,African Americans 2 344±119 and Hispanics 2 364±104,P>0.05).The BBR was lower in subjects with higher breath-and body-temperatures(P<0.05)and it also decreased with longer exhalation times into the breath-analyzer(P<0.001).In the post-absorptive state,none of the 100 subjects had a BBR of less than 2 100∶1.
