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PubMed1998

A comparison of repeated high doses and repeated standard doses of epinephrine for cardiac arrest outside the hospital. European Epinephrine Study Group.

BACKGROUND: Clinical trials have not shown a benefit of high doses of epinephrine in the management of cardiac arrest. We conducted a prospective, multicenter, randomized study comparing repeated high doses of epinephrine with repeated standard doses in cases of out-of-hospital cardiac arrest. METHODS: Adult patients who had cardiac arrest outside the hospital were enrolled if the cardiac rhythm continued to be ventricular fibrillation despite the administration of external electrical shocks, or if they had asystole or pulseless electrical activity at the time epinephrine was administered. We randomly assigned 3327 patients to receive up to 15 high doses (5 mg each) or standard doses (1 mg each) of epinephrine according to the current protocol for advanced cardiac life support. RESULTS: In the high-dose group, 40.4 percent of 1677 patients had a return of spontaneous circulation, as compared with 36.4 percent of 1650 patients in the standard-dose group (P=0.02); 26.5 percent of the patients in the high-dose group and 23.6 percent of those in the standard-dose group survived to be admitted to the hospital (P=0.05); 2.3 percent of the patients in the high-dose group and 2.8 percent in the standard-dose group survived to be discharged from the hospital (P=0.34). There was no significant difference in neurologic status according to treatment among those discharged. High-dose epinephrine improved the rate of successful resuscitation in patients with asystole, but not in those with ventricular fibrillation. CONCLUSIONS: In our study, long-term survival after cardiac arrest outside the hospital was no better with repeated high doses of epinephrine than with repeated standard doses.

Adrenergic Agonists↗

PubMed2002

A randomized comparison of a sirolimus-eluting stent with a standard stent for coronary revascularization.

BACKGROUND: The need for repeated treatment of restenosis of a treated vessel remains the main limitation of percutaneous coronary revascularization. Because sirolimus (rapamycin) inhibits the proliferation of lymphocytes and smooth-muscle cells, we compared a sirolimus-eluting stent with a standard uncoated stent in patients with angina pectoris. METHODS: We performed a randomized, double-blind trial to compare the two types of stents for revascularization of single, primary lesions in native coronary arteries. The trial included 238 patients at 19 medical centers. The primary end point was in-stent late luminal loss (the difference between the minimal luminal diameter immediately after the procedure and the diameter at six months). Secondary end points included the percentage of in-stent stenosis of the luminal diameter and the rate of restenosis (luminal narrowing of 50 percent or more). We also analyzed a composite clinical end point consisting of death, myocardial infarction, and percutaneous or surgical revascularization at 1, 6, and 12 months. RESULTS: At six months, the degree of neointimal proliferation, manifested as the mean (+/-SD) late luminal loss, was significantly lower in the sirolimus-stent group (-0.01+/-0.33 mm) than in the standard-stent group (0.80+/-0.53 mm, P<0.001). None of the patients in the sirolimus-stent group, as compared with 26.6 percent of those in the standard-stent group, had restenosis of 50 percent or more of the luminal diameter (P<0.001). There were no episodes of stent thrombosis. During a follow-up period of up to one year, the overall rate of major cardiac events was 5.8 percent in the sirolimus-stent group and 28.8 percent in the standard-stent group (P<0.001). The difference was due entirely to a higher rate of revascularization of the target vessel in the standard-stent group. CONCLUSIONS: As compared with a standard coronary stent, a sirolimus-eluting stent shows considerable promise for the prevention of neointimal proliferation, restenosis, and associated clinical events.

Coronary Disease↗

PubMed2002

A randomized controlled trial comparing the hair apposition technique with tissue glue to standard suturing in scalp lacerations (HAT study).

STUDY OBJECTIVE: We evaluate a new technique of treating scalp lacerations, the hair apposition technique (HAT). After standard cleaning procedures, hair on both sides of a laceration is apposed with a single twist. This is then held with tissue adhesives. HAT was compared with standard suturing in a multicenter, randomized, prospective trial. METHODS: All linear lacerations of the scalp less than 10 cm long were included. Severely contaminated wounds, actively bleeding wounds, patients with hair strand length less than 3 cm, and hemodynamically unstable patients were excluded. Patients were randomized to receive either HAT or standard suturing, and the time to complete the wound repair was measured. All wounds were evaluated 7 days later in a nonblinded manner for satisfactory wound healing, scarring, and complications. RESULTS: There were 96 and 93 patients in the study and control groups, respectively. Wound healing trended toward being judged more satisfactory in the HAT group than standard suturing (100% versus 95.7%; P =.057; effect size 4.3%; 95% confidence interval 0.1% to 8.5%). Patients who underwent HAT had less scarring (6.3% versus 20.4%; P =.005), fewer overall complications (7.3% versus 21.5%; P =.005), significantly lower pain scores (median 2 versus 4; P <.001), and shorter procedure times (median 5 versus 15 minutes; P <.001). There was a trend toward less wound breakdown in the HAT group (0% versus 4.3%; P =.057). When patients were asked whether they were willing to have HAT performed in the future, 84% responded yes, 1% responded no, and 15% were unsure. CONCLUSION: HAT is equally acceptable and perhaps superior to standard suturing for closing suitable scalp lacerations. Advantages include fewer complications, a shorter procedure time, less pain, no need for shaving or removal of stitches, similar or superior wound healing, and high patient acceptance. HAT has become our technique of choice for suitable scalp lacerations.[Ong Eng Hock M, Ooi SBS, Saw SM, Lim SH. A randomized controlled trial comparing the hair apposition technique with tissue glue to standard suturing in scalp lacerations (HAT study).

Adolescent↗

PubMed2001

The effect of standard care, ibuprofen, and music on pain relief and patient satisfaction in adults with musculoskeletal trauma.

OBJECTIVE: The purposes of this study were to determine the most effective nursing intervention to decrease pain for patients with minor musculoskeletal trauma and moderate pain at triage and to examine patient satisfaction. METHODS: Patients were assigned to 1 of 3 intervention groups: (1) standard care (ice, elevation, and immobilization); (2) standard care and ibuprofen; or (3) standard care and music distraction. Patients were monitored for pain ratings for 60 minutes. Patients who sustained minor musculoskeletal trauma within the past 24 hours and presented with pain ratings of 4 or greater were included. Two patient satisfaction questions were asked upon discharge from the emergency department. RESULTS: Seventy-seven patients met the inclusion criteria. No differences in pain ratings between groups were demonstrated. A statistically significant reduction in pain for all patients occurred at 30 minutes (F = 16.18, P <.01) and was maintained at 60 minutes. However, 70% of patients continued to report pain ratings of 4 or greater (on a scale of 1 to 10) at 60 minutes. The reduction in pain was not found to be clinically significant.Eighty-four percent of patients stated that they were more satisfied with their overall care in the emergency department because of the immediate attention to pain relief they received at triage. No differences in satisfaction existed between treatment groups, although patients who reported higher pain ratings expressed statistically significant lower satisfaction with pain management scores (F = 9.375, P =.003). CONCLUSION: None of the therapies-standard care (ice, elevation, immobilization), standard care with ibuprofen, or standard care with music distraction-provided clinically significant pain relief to patients who had minor musculoskeletal trauma (ie, sprains and fractures) and moderate pain at triage. Interestingly, satisfaction scores were sometimes positive, even when pain was not relieved.

Adult↗

PubMed2001

Safety of a new micronized formulation of isotretinoin in patients with severe recalcitrant nodular acne: A randomized trial comparing micronized isotretinoin with standard isotretinoin.

BACKGROUND: Isotretinoin is a very effective drug for treating severe recalcitrant nodular acne. A new micronized formulation of isotretinoin has been shown to be clinically equivalent to standard isotretinoin with improved bioavailability and minimal food effect. The safety profile of the micronized formulation has not been described previously. OBJECTIVE: The objective of this article is to report the incidence and intensity of adverse events found in a comparative, double-blind efficacy study that showed clinical equivalence of the new micronized formulation of isotretinoin and the standard isotretinoin formulation (Accutane). METHODS: Six hundred patients with severe recalcitrant nodular acne were treated with micronized isotretinoin (n = 300) under fasted conditions or standard isotretinoin (n = 300) under fed conditions. One cohort received single daily doses of 0.4 mg/kg of micronized isotretinoin without food and the other cohort received 1.0 mg/kg per day of standard isotretinoin in two divided doses with food. Adverse events were monitored during 20 weeks of drug therapy. RESULTS: The proportion of adverse events in most body systems was generally lower in patients receiving micronized isotretinoin than in those receiving standard isotretinoin. CONCLUSION: Micronized isotretinoin appears to have a safety profile similar to that of standard isotretinoin and to carry a lower risk of mucocutaneous events and hypertriglyceridemia.

Acne Vulgaris↗

PubMed2002

Recommended standards for reports dealing with arteriovenous hemodialysis accesses.

The incidence rate of treated end-stage renal disease in the united states is 180 per million and continues to rise at a rate of 7.8% per year. Arteriovenous hemodialysis access (AV access) creation and maintenance are two of the most difficult issues associated with the management of patients on hemodialysis. The 1-year complication rate of a primary prosthetic AV access for hemodialysis ranges from 33% to 99%. Various investigators report on patency and complications of AV access. However, it is rather difficult to compare outcomes because of the wide variety of access materials, configurations, locations, risk factors, and quality of inflow and outflow vessels. Although there have been reporting standards for dialysis access endovascular interventions and for central venous access placement, standards regarding surgical access placement and its revision are lacking. The "Dialysis Outcome Quality Initiative," published by the National Kidney Foundation, provides recommendations for optimal clinical practices aimed at improving dialysis outcome and patient survival. This reporting standards document is not meant to be a "practice guidelines" or "best practices" document. Rather, the purpose of this document is to provide standardized definitions related to AV access procedures and to recommend reporting standards for patency and complications, to be used by surgeons, nephrologists, and interventional radiologists, that will permit meaningful comparisons among AV access procedures. The terms, definitions, and categories featured in this article have been approved by the Committee on Reporting Standards of the Society for Vascular Surgery and the American Association for Vascular Surgery and should be observed in preparing manuscripts on AV accesses for submission to the Journal Of Vascular Surgery.

Arteriovenous Shunt, Surgical↗

PubMed2000

The ambiguity and the exigency: clarifying 'standard of care' arguments in international research.

This paper examines the concept of a 'standard of care' as it has been used in recent arguments over the ethics of international human-subjects research. It argues that this concept is ambiguous along two different axes, with the result that there are at least four possible standard of care arguments that have not always been clearly distinguished. As a result, it has been difficult to assess the implications of opposing standard of care arguments, to recognize important differences in their supporting rationales, and even to locate the crux of the disagreement in some instances. The goal of the present discussion, therefore, is to disambiguate the concept of a 'standard of care' and to highlight the areas of genuine disagreement among different standards. In the end it is argued that one standard of care argument in particular is more complex than either its proponents or its critics may have recognized and that understanding this possibility opens up a potentially promising avenue of inquiry that remains to be carefully explored.

Clinical Trials as Topic↗

PubMed2004

Performance requirements of physically strenuous occupations: validating minimum standards for muscular strength and endurance.

Employment rights legislative mandates passed in the USA over the last three decades emphasize the importance of validating performance standards for physically strenuous occupations. This study validated minimally acceptable standards for the muscular strength and endurance necessary to perform fire suppression activities. Incumbent firefighters (n=153) selected for key demographic characteristics completed a simulated set of firefighting tasks (Fire Suppression Evolution) and then a Predictor Test Battery of physical abilities tests. Regression analysis revealed that three predictor test items (hose drag/high rise pack carry; arm lift; arm endurance) combined to significantly predict performance time of the Fire Suppression Evolution (p < or =0.01). Firefighters (n=41) rating videotaped performance times of the Fire Suppression Evolution determined that more than one-half a standard deviation slower than the mean time established by the incumbents reflected unacceptable performance. Approximately 80% of incumbent firefighters passed the minimally acceptable performance standard. Use of the 3-predictor test battery would correctly identify 89% of successful performers and 72% of unsuccessful performers. This study demonstrates that validation of minimal physical performance standards will identify a cohort of individuals with a high probability of not being able to perform critical fire suppression activities. This finding has important implications for examining the relationship between physical performance standards and medical and economic outcomes.

Adult↗

PubMedDate not supplied

Manual materials handling capabilities in non-standard postures.

Research efforts to establish manual materials handling (MMH) capabilities of individuals and populations have been conducted for many years. Most of the previous efforts have explored 'standard postures', utilizing two-handed, symmetric, sagittal plane MMH using unrestricted postures. Recognizing that many industrial MMH activities do not utilize 'standard postures', recent research projects have explored psychophysically determined MMH capacities in a variety of non-standard postures. Among the non-standard postures examined were: twisting while lifting or lowering, lifting and lowering from lying, sitting, kneeling, and squatting positions, and carrying loads under conditions of constricted ceiling heights. This paper presents the results of a series of previous research efforts at Texas Tech University. The results are presented in the form of population capabilities of both males and females for 99 MMH tasks using 'non-standard postures'. The data tables contain means and standard deviations of the data, as well as percentile distributions for the subject populations. Sample sizes for the experimental populations ranged from 45 to 50 subjects of each sex in the first three experiments to 20 subjects of each sex in the fourth set of experiments.

Adolescent↗

PubMed1999

Effect of current and forthcoming European legislation and standardization on the setting of quality specifications by laboratories.

A network of national and international guidelines and directives developed in the last few decades by various bodies will lead to a new concept of total quality for medical laboratory services comprising legislative regulations on national and international levels, standardizations backed up by legislation and recommendations of professional societies. One example is the IVD Directive of the European Community. It will not only stimulate accreditation in the field of laboratory medicine, but also necessitate numerous standardization activities which are presently co-ordinated by the European Committee for Standardization (CEN). Another standardization example is the development of quality management systems, mainly by ISO. The ISO 9000 series has become the most successful family of standards world-wide. Meanwhile, specific standards for the needs of laboratories (ISO 17025), and in particular of medical laboratories (ISO 15189), are being worked out. A new trend to develop quality management systems towards total quality management systems can be observed including additional aspects such as economic and quality interests of society, customers and owners of laboratories. The goal of all activities is to create a network of confidence which provides some guarantee to the clients, i.e. the physicians and their patients, that they will receive a high-quality medical laboratory service.

Clinical Laboratory Techniques↗

PubMed1984

Evaluating the use of occupational standards for controlling toxic air pollutants.

Currently, the U.S. Environmental Protection Agency has established air standards for relatively few chemicals. As a result, state agencies are faced with controlling air contaminants for a large number of chemicals posing potential public health threats. Use of occupational standards as a basis for deriving ambient air guidelines is a method used by states to control air toxics. This standard development approach is reviewed by considering the differences in the health basis and numerical values which often occur among the occupational standards set by OSHA, NIOSH and ACGIH. This study indicated that careful selection should be made of the most appropriate occupational standard to use to protect public health. A comparison is made of chemicals regulated by various state air toxic programs using occupational standards lowered by a safety factor to concentrations established by the U.S. EPA. It was found that the air guidelines vary, but the degree of stringency can be comparable.

Air Pollutants, Occupational↗

PubMed1989

The need for a more robust ozone air quality standard.

The present National Ambient Air Quality Standard for ozone has many statistical problems, including use of extreme values which have inherent large fluctuations, a compliance test that can gradually lower the target of the design value below the standard level, and inconsistencies between the number-of-exceedances criterion and the design value. The above problems can be avoided or minimized by using a more robust statistic, such as the 95th percentile, and applying a statistical compliance test, without sacrificing the stringency of the standard. Analysis of EPA's ozone data shows that the annual 95th percentiles and their three-year means have less variability than the annual second highest values and the fourth highest values in three years, respectively. At t test for the mean of the annual 95th percentiles is proposed for compliance testing not only to preserve the averaging concept of the present standard, but also to take account of ozone concentration fluctuations in order to increase the stability of the compliance status of a site or a Metropolitan Statistical Area. A procedure is provided to adjust the level of the 95th-percentile standard so that the stringency of the present standard is preserved.

Air Pollutants, Occupational↗

PubMed1992

NCLAN results and their application to the standard-setting process: protecting vegetation from surface ozone exposures. National Crop Loss Assessment Network.

The current form of the standard is not appropriate for protecting vegetation from O3 exposures. As an alternative to the current form of the standard, it has been suggested in the literature that a maximum cumulative 3-month SUM06 O3 exposure index be used as the form of a secondary standard to protect agricultural crops. However, applying this index may result in inconsistent protection for vegetation. It appears that cumulative indices will have to be combined with other parameters to accurately quantify the occurrence of high hourly average concentrations. This paper describes the characterization of the hourly O3 exposures in selected National Crop Loss Assessment Network (NCLAN) experiments and discusses the application of the results to the standard-setting process. Our results indicated that, in most cases, the NCLAN experimental data we analyzed appeared to support the observation that the repeated occurrences of hourly average O3 concentrations of 0.10 ppm and higher result in adverse effects on vegetation. For the NCLAN experiments, the characterized distributions reflected the ability of the high hourly average concentrations to affect crop yield reduction. Prior to suggesting a new form of the secondary standard, it will be important to carefully characterize the specific regimes responsible for affecting vegetation and identify the important components of those regimes responsible for the effects. By applying this approach, it should be possible to limit the occurrence of inconsistent results when applying a new form of the secondary standard.

Air Pollutants, Occupational↗

PubMed1999

Elective transumbilical compared with standard laparoscopic cholecystectomy.

OBJECTIVE: To compare the transumbilical technique of laparoscopic cholecystectomy with standard laparoscopic cholecystectomy. DESIGN: Randomised open study. SETTING: Teaching hospital, Italy. SUBJECTS: 90 patients who required elective cholecystectomy under general anaesthesia. INTERVENTIONS: Standard laparoscopic cholecystectomy through 4 ports or transumbilical cholecystectomy through 2 ports. MAIN OUTCOME MEASURES: Amount of pain and analgesia, cost, side effects, and cosmesis. RESULTS: 25 patients were excluded from analysis (8 in the standard group because relevant data were not recorded; and 17 in the transumbilical group in 4 of whom relevant data were not recorded, and 13 for technical reasons). 32 patients who had standard, and 25 who had transumbilical cholecystectomy had operative cholangiograms. There were no complications, no side effects, and no conversions to open cholecystectomy. Those who had transumbilical cholecystectomy had significantly lower pain scores (p<0.05) and required significantly less analgesia during the first 24 hours (p<0.05) than those who had standard laparoscopic cholecystectomy. CONCLUSION: Once the learning curve has been completed, transumbilical cholecystectomy is possible without some of difficulties associated with standard laparoscopic cholecystectomy.

Adult↗

PubMed1983

Critical review of international standards for respiratory protective equipment - II. Gas and vapor removal efficiency and fit testing.

The purpose of a Respiratory Protective Equipment (R.P.E.) standard is to assure that a minimum level of performance is reached by the respirator. Standards from a number of countries and standards organizations require that certain specifications are met in construction and that respirators be evaluated by specific performance tests. This is the second of three critical review papers related to respirator standards. We here summarize in tabular form, compare and critically review how the different countries or standards organizations test respirators designed for protection against gases and vapors for leakage due to improper fitting of the respirator facepiece and gas and vapor removal efficiency of the cartridge/canister. Two general aspects as they relate to removal capacity testing are discussed. The first issue deals with the selection of test gases and vapors that best represent the sorptive behavior of a class or group of compounds. The second issue deals with the extrapolation of laboratory testing under rigidly specified conditions to conditions of actual use. Fit testing varies from country to country. The fit testing conditions specified in the various standards are summarized along with a discussion of test material selection, the test panel selection, and the range of controlled test activities.

Air Pollutants, Occupational↗

PubMed1995

Development of an ISO 9000 compatible occupational health standard: defining the issues.

Corporate ISO 9000 registration is gaining international acceptance as the hallmark of quality system achievement. The International Organization for Standardization (ISO) is currently drafting environmental standards that will complement ISO 9000. Should the international community also consider development of an ISO 9000-compatible occupational safety and health management standard (OSHMS)? To determine the advantages and disadvantages of this issue, the investigators conducted interviews with government and private sector experts, reviewed publicly accessible ISO documents, and evaluated published literature germane to the subject. Major advantages of an ISO OSHMS were the harmonization of national standards, maximizing Occupational Safety and Health Administration (OSHA) efficiency through third-party registration audits, and increased emphasis on employee-driven health and safety programs. Major disadvantages were the single vote of the American National Standards Institute at international proceedings, direct and indirect program development costs, potential unethical or incompetent conduct of registrars, and the logistics of developing an acceptable standard to all stakeholders. Some unresolved issues were the inevitability of an ISO OSHMS, auditor indemnification, and the scope of OSHA participation. Industrial health and safety professionals should initiate formal discussion on this issue to elaborate on findings presented here and to establish a consensus on future activities.

Occupational Health↗

PubMed1994

Quality standard for antimicrobial prophylaxis in surgical procedures. The Infectious Diseases Society of America.

OBJECTIVE: The objectives of this quality standard are 1) to provide an implementation mechanism that will facilitate the reliable administration of prophylactic antimicrobial agents to patients undergoing operative procedures in which such a practice is judged to be beneficial and 2) to provide a guideline that will help local hospital committees formulate policies and set up mechanisms for their implementation. Although standards in the medical literature spell out recommendations for specific procedures, agents, schedules, and doses, other reports document that these standards frequently are not followed in practice. OPTIONS: We have specified the procedures in which the administration of prophylactic antimicrobial agents has been shown to be beneficial, those in which this practice is widely thought to be beneficial but in which compelling evidence is lacking, and those in which this practice is controversial. We have examined the evidence regarding the optimal timing of drug administration, the optimal dose, and the optimal duration of prophylaxis. OUTCOMES: The intended outcome is more uniform and reliable administration of prophylactic antibiotics in those circumstances where their value has been demonstrated or their use has been judged by the local practicing medical community to be desirable. The result should be a reduction in rates of postoperative wound infection with a limitation on the quantities of antimicrobial agents used in circumstances where they are not likely to help. EVIDENCE: Many prospective, randomized, controlled trials comparing placebo with antibiotic and comparing one antibiotic with another have been conducted. In addition, some trials have compared the efficacy of different doses or methods of administration. Other papers have reported on the apparent efficacy of administration at different times and on actual practice in specific communities. Only a small group of relevant articles found through 1993 are cited herein. When authoritative reviews are available, these--rather than an exhaustive list of original references--are cited. VALUES: We assumed that reducing rates of postoperative infection was valuable but that reducing the total amount of antimicrobial agents employed was also worthwhile. The cost of and morbidity attributable to postoperative wound infections should be weighed against the cost and potential morbidity associated with excessive use of antimicrobial agents. BENEFITS, HARMS, AND COSTS: More reliable administration of antimicrobial agents according to recognized guidelines should prevent some postoperative wound infections while lowering the total quantity of these drugs used. No harms are anticipated. The costs involved are those of the efforts needed on a local basis to design and implement the mechanism that supports uniform and reliable administration of prophylactic antibiotics. RECOMMENDATIONS: All patients for whom prophylactic antimicrobial agents are recommended should receive them. The agents given should be appropriate in light of published guidelines. A short duration of prophylaxis (usually < 24 hours) is recommended. VALIDATION: More than 50 experts in infectious disease and 10 experts in surgical infectious disease and surgical subspecialties reviewed the standard. In addition, the methods for its implementation were reviewed by the American Society of Hospital Pharmacists. SPONSORS: The Quality Standards Subcommittee of the Clinical Affairs Committee of the Infectious Disease Society of America (IDSA) developed the standard. The subcommittee was composed of representatives of the IDSA (Drs. Gross and McGowan), the Society for Hospital Epidemiology of America (Dr. Wenzel), the Surgical Infection Society (Dr. Dellinger), the Pediatric Infectious Disease Society (Dr. Krause), the Centers for Disease Control and Prevention (Dr. Martone), the Obstetrics and Gynecology Infectious Diseases Society (Dr. Sweet), and the Association of Practitioners of Infection Contr

Anti-Bacterial Agents↗

PubMed2000

IPEM guidelines on dosimeter systems for use as transfer instruments between the UK primary dosimetry standards laboratory (NPL) and radiotherapy centres.

United Kingdom dosimetry codes of practice have traditionally specified one electrometer for use as a secondary standard, namely the Nuclear Enterprises (NE) 2560 NPL secondary standard therapy level exposure meter. The NE2560 will become obsolete in the foreseeable future. This report provides guidelines to assist physicists following the United Kingdom dosimetry codes of practice in the selection of an electrometer to replace the NE2560 when necessary. Using an internationally accepted standard (BS EN 60731:1997) as a basis, estimated error analyses demonstrate that the uncertainty (one standard deviation) in a charge measurement associated with the NE2560 alone is approximately 0.3% under specified conditions. Following a review of manufacturers' literature, it is considered that modern electrometers should be capable of equalling this performance. Additional constructural and operational requirements not specified in the international standard but considered essential in a modern electrometer to be used as a secondary standard are presented.

Guidelines as Topic↗

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