Rapid measurement of blood cholesterol: evaluation of a new instrument

Rapid and reliable techniques for the measurement of blood cholesterol are a necessary first step in implementing effective mass screening efforts to reduce the risks of cardiovascular disease. This paper reports preliminary data gathered on the Kodak Ektachem DT60, one of the first of a new generation of dry chemistry analyzers to appear on the market. The results of the first study demonstrated high reproducibility of the methodology (r = .98, p less than .0001) but showed an average 25 mg/dL underestimate of total blood cholesterol as compared with a standardized lipid laboratory. Changes in the manufacturer's calibration protocol in the second study with two other DT60s reduced this bias on serum samples to -18 mg/dL. A third study using fresh blood samples found a difference of 3-11 mg/dL between the two DT60s and the laboratory. A significant difference between the two analyzers was also found. Alternatives are available to enable those who use this instrument to correct for the observed bias. Despite some problems, several other advantages of the technology lend support for its expanded use in public health interventions.     

无创血压检测仪质量控制检测方法分析及应用特点

目的：探讨无创血压检测仪质量控制的检测方法及常见问题,分析两种无创血压质量检测仪的功能和特点,提高质量控制检测技术。方法：采用美国“FLUKE”BP Pump2型无创血压质量检测仪和奥利科BP-SiM型无创血压质量检测仪,对监护仪中无创血压模块进行检测,对结果进行分析。结果：定期的质量控制检测可以有效提高无创血压监护仪的可靠性,降低不合格率。结论：使用两种无创血压质量检测仪保障了多参数监护仪的质量安全。通过定期检测,杜绝了不合格的监护仪在临床的应用,确保了临床诊断的准确性和患者的生命安全。     

四种测氡仪器测量效果的比较研究

目的对我国常用的四种现场氡测量仪器RAD7、RTM2100、RTM1688和PQ2000的性能和测量结果进行比较。方法选择一个普通房间和高氡地下室进行了氡气含量的实地测量和比较。结果 PQ2000稳定性和可靠性最好,两个浓度的测量值与氡室参考值的R均为2%;RTM2100实测值波动较大,低水平测量时应注意延长测量时间;RAD7型连续测氡仪需要进行干燥处理,否则结果会偏低。结论四种连续测氡仪在不同环境的测量结果的可靠性均在有关标准的允许范围之内。     

The validity of the Reflotron as a screening tool for blood cholesterol

Screening for blood cholesterol levels has become an essential need in many countries. The aim of this study was to evaluate the performance of Reflotron analyzer in screening for blood cholesterol in terms of its precision and accuracy. We have compared the results obtained by the Reflotron with those obtained by a standard hospital laboratory procedure for the same samples. An optimal precision that met the 1992 LSP standards for precision was observed (CV = 2.27%). On the other hand, a suboptimal accuracy of Reflotron was detected, where more than 80% of the Reflotron values differed from the reference laboratory values by more than 5%. As a consequence, 21% of individuals were misclassified as normal due to the very low sensitivity in spite of the optimum specificity observed for the Reflotron. Using the receiver operating characteristic curve analysis, the optimum cut-off points giving the best validity values for the test were 170 mg/dl and 190 mg/dl (4.4 mmol/L and 4.9 mmol/L) for the border-line and true hypercholesterolemia, respectively. At these levels, sensitivity was 0.89 and 0.86, specificity 0.93 and 0.93, and positive predictive value was 0.91 and 0.82, respectively. Considering some limitations of the study, it is concluded that the Reflotron could be of more potential validity for the use in cholesterol measurement surveys when the recommended cut-off points are used.     

Precision and accuracy of a portable blood analyzer system during cholesterol screening.

The precision and accuracy of two Kodak Ektachem DT-60 portable blood analyzers were assessed in a model (research) cholesterol screening program in Rochester, New York. Between June and October 1987, a total of 8,573 people underwent a cholesterol screening held in a movable trailer. A wide variety of temperature, humidity, and other potentially adverse conditions were encountered during the screening period. Between-run coefficients of variation ranged from 1.9 percent to 4.8 percent per month; average bias compared to a Reference Laboratory method ranged between +0.2 percent and +2.0 percent. Both precision and accuracy met currently recommended standards for cholesterol testing in the United States.     

An instrument for measuring bacterial penetration through fabrics used for barrier clothing.

A new instrument has been designed to measure the penetration by rubbing of bacteria from cloth contaminated in the nursing of burn patients through fabrics designed for barrier garments. Most fabrics tested dry reduced the transfer of bacteria from the source cloth to about 10%, irrespective of the results of air filter tests, which agrees with mock nursing results. When the fabrics were tested against a wet surface, the transfer of bacteria rapidly reached 100% if the fabrics had a high wettability, but was slower for fabrics with a low wettability. Through closely woven waterproofed cotton, transfer was 5--25%, but increased three- to four-fold after ten launderings, in line with the water absorption. Transfer through plastic-laminated material was less than 1%. The results suggest that barrier garments should be made either of plastic or of recently waterproofed closely woven cotton at points of contact between nurse and patient where the clothes may be wetted by bacteria-containing wound secretions.     

Assessing population-based programs to reduce blood cholesterol level and saturated fats

This article reviews seven community-based programs for prevention of cardiovascular disease and their effects on blood cholesterol levels and saturated fat intake. In two programs, cholesterol levels were reduced more in the intervention area than in the reference area. In two other programs, cholesterol increased less in the intervention area than in the reference area. In one program, cholesterol levels initially fell in the intervention group and increased in the reference group; after the first 4 years, the levels also started to increase in the intervention group. The final two programs reduced cholesterol equally in both groups. Only two programs reported on the intake of saturated fats; in both, intake of saturated fat was reduced more in the intervention area than in the reference populations. In one program area, total intake of fat was reduced more than in the reference area. Published data do not allow us to draw conclusions regarding which components of the programs were most important. These studies show that the average blood cholesterol level can be affected in a general population.     

Variability in cholesterol measurements in a worksite cholesterol screening program.

Worksite cholesterol screening programs are becoming increasingly prevalent. Variability in cholesterol measurements frequently renders the interpretation of single or repeated cholesterol determinations problematic, complicating employee counseling within screening programs. In the setting of a corporate cholesterol screening program, this study quantifies variability in cholesterol measurements and calculates a 90% confidence interval (CI) for cholesterol measurements. We chose 15 men and 15 women to represent a broad range of cholesterol values. We obtained duplicate samples of blood from each subject at one-week intervals for a total of three weeks. We performed total cholesterol measurements in duplicate twice weekly on each blood sample for three weeks, yielding a total of 36 measurements per subject. Components of variability were estimated using a hierarchical random effects analysis of variance (ANOVA) model. The coefficients of variation for biologic and analytic variation were 5.2% and 3.4% for men and 4.7% and 3.2% for women. CIs were +/- 10.2% for men and +/- 9.3% for women. As a result of this variation, we recommend the routine use of CIs when discussing cholesterol measurements with patients.     

Training health professionals and lay volunteers to deliver cholesterol screening and education programs

The National Heart, Lung, and Blood Institute of the National Institutes of Health launched the National Cholesterol Education Program (NCEP) in 1985. With the goal of reducing the prevalence of elevated blood cholesterol in the United States, the NCEP aims to raise awareness and understanding in both health professionals and the general public of high blood cholesterol levels as a risk factor for coronary heart disease. Public interest in blood cholesterol measurement has created an enormous market for cholesterol screening and education programs. The importance of quality screening and educational services was recognized by the NCEP, which has urged the training of all personnel involved in public cholesterol screenings. This paper presents models for training lay volunteers and health professionals to deliver quality public screening programs for high blood cholesterol that are consistent with NCEP recommendations. Blood cholesterol screening, counseling, and referral (SCORE) programs are key intervention strategies of the Pawtucket Heart Health Program (PHHP), a cardiovascular disease prevention research program in Pawtucket, RI. This paper describes the PHHP volunteer training and certification program for cholesterol SCOREs and the demographics of screening volunteers. With the goal of improving the quality of cholesterol screening and education programs nationally, the Cholesterol Training Center (CTC) was established in 1988. Using models established by PHHP, the center developed training workshops to help health professionals initiate, update, expand, or enhance training for cholesterol screening and education programs. CTC training protocols and the characteristics of workshop participants are described, and the workshops' effects on participants' knowledge and self-sufficiency are discussed.     

青岛地区新生儿脐血胆固醇测定早期筛查家族性高胆固醇血症

目的 采用脐血检测胆固醇用以筛查家族性高胆固醇血症患儿,探讨早期筛查家族性高胆固醇血症的适宜方法。 方法 收集1 000例产妇静脉血及其足月新生儿脐血测定胆固醇水平,以2.50 mmol/L为切值筛选可疑病例,通过调查家族史和基因检测确诊患儿。结果 足月新生儿脐血胆固醇均值为(1.81±0.46)mmol/L;≥2.50 mmol/L切值者70例,确诊家族性高胆固醇血症患儿2例,发生率为1/500;脐血胆固醇不受母血胆固醇水平的影响。结论 新生儿脐血胆固醇测定早期筛查家族性高胆固醇血症的方法简便,结果可靠,适宜人群大规模筛查中采用。     

Comparisons of referral criteria for public screening of blood cholesterol levels

Total and high-density lipoprotein (HDL) cholesterol levels of 2,387 adults were screened at a worksite and a bloodbank. Hypothetical referral decisions were made according to three sets of guidelines: the 1984 National Institutes of Health Consensus Conference guidelines (NIHCC), a single referral cutpoint of 5.2 millimoles per liter (mmol per L), and the current National Cholesterol Education Program (NCEP) guidelines for screening in physicians' office. Under the NIHCC guidelines, 31 percent of the participants would have been referred to their physicians, 32 percent under the NCEP guidelines, and 56 percent would have been referred had the 5.2 mmol per L cutpoint been used. Twenty-four percent of the participants would have been referred under both the NIHCC and NCEP guidelines; 7 percent would have been referred under the NIHCC guidelines, but not the NCEP's. Eight percent would have been referred under the NCEP guidelines, but not the NIHCC's. Those who would have been referred were older, and more likely to be male and to have low levels of HDL cholesterol than the 7 percent who would have been referred under NIHCC guidelines only. All of the 8 percent had coronary heart disease, or two or more other coronary risk factors, whereas none of the 7 percent did. If low HDL had been used as a risk factor under NCEP guidelines, the number of persons referred would have increased slightly (to 34 percent) and low HDL levels would have become one of the most prevalent risk factors. The researchers concluded that public cholesterol screening programs should use the NCEP guidelines (with or without HDL), rather than the NIHCC guidelines, or a single 5.2 mmol per L cutpoint.     

Test of a noninvasive instrument for measuring hemoglobin concentration

A colorimetric instrument for the noninvasive quantification of hemoglobin, designed using color shades resembling those observed in the conjunctiva, was tested. The instrument's colors are contrasted against the color of the conjunctiva to measure hemoglobin content. Sensitivity, specificity, negative predictive value, and false-negative value were estimated to test the instrument's accuracy; kappa coefficients were used to estimate inter- and intraobserver variability. Physician field evaluations of conjunctiva color for the screening of anemia, reported in the literature, have had sensitivities and specificities as high as 70%. Readings with the instrument demonstrated a 63% sensitivity, 72% specificity, and 38% false negatives for screening hemoglobin values of less than or equal to 13 g/dl. The interobserver kappa coefficients for three pairs of readers were good to excellent for the same hemoglobin screening value. Statistically significant differences were noted, however, between observers during the reliability test. The instrument can be used by unskilled personnel to improve their decision-making about whom to send for further care or for supplementation with iron.     

Participation in breast screening programs: a review

Despite recommendations by the American Cancer Society and other organizations for use of screening mammography, data on reported utilization of this procedure by American women show that these guidelines are not being met. We reviewed published studies that reported participation rates or that examined factors associated with participation in selected breast screening programs. In general, women at high risk due to age and family or personal history of breast disease were not more likely to participate in breast screening programs than women without those risk factors. The one group of variables that was fairly consistently associated with participation was the practice of other preventive health behaviors. Women who expressed more concern about their health and who were more knowledgeable about breast cancer screening and its benefits also were more likely to complete mammography. Approaches to increasing participation are discussed in the context of the literature on this subject.     

Development of a brief diabetes distress screening instrument

PURPOSE Previous research has documented that diabetes distress, defined as patient concerns about disease management, support, emotional burden, and access to care, is an important condition distinct from depression. We wanted to develop a brief diabetes distress screen instrument for use in clinical settings.METHODS We assessed 496 community-based patients with type 2 diabetes on the previously validated, 17-item Diabetes Distress Scale (DDS17) and 6 biobehavioral measures: glycated hemoglobin (HbA_1c); non–high-density-lipoprotein (non-HDL) cholesterol; kilocalories, percentage of calories from fat, and number of fruit and vegetable servings consumed per day; and physical activity as measured by the International Physical Activity Questionnaire.RESULTS An average item score of ≥3 (moderate distress) discriminated high- from low-distressed subgroups. The 4 DDS17 items with the highest correlations with the DDS17 total (r = .56–.61) were selected. Composites, comprised of 2, 3, and 4 of these items (DDS2, DDS3, DDS4), yielded higher correlations (r=.69–.71). The sensitivity and specificity of the composites were .95 and .85, .93 and .87, and .97 and .86, respectively. The DDS3 had a lower sensitivity and higher percentages of false-negative and false-positive results. All 3 composites significantly discriminated subgroups on HbA_1c, non-HDL cholesterol, and kilocalories consumed per day; none discriminated subgroups on fruit and vegetable servings consumed per day; and only the DDS3 yielded significant results on the International Physical Activity Questionnaire. Because of its psychometric properties and brevity, the DDS2 was selected as a screening instrument.CONCLUSIONS The DDS2 is a 2-item diabetes distress screening instrument asking respondents to rate on a 6-point scale the degree to which the following items caused distress: (1) feeling overwhelmed by the demands of living with diabetes, and (2) feeling that I am often failing with my diabetes regimen. The DDS17 can be administered to those who have positive findings on the DDS2 to define the content of distress and to direct intervention.     

医学支物实验热源仪的研制

本文描述了一种以φ＝3mm小直径半导体PN结作为热传感器,测温范围0－45℃,测量分辨率为0．1℃,具有64通道,用于测量医学实验动物体温的热源仪。由于采用两点总体温度标定方法,使硬件电路调整极为方便,采用这种标定方法是本仪器的特点。