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[Systematic quality control programme for colonoscopy in an endoscopy centre in Norway].

BACKGROUND: Colonoscopy is regarded as the gold standard for diagnosis of colorectal disease, and increasingly considered a primary screening approach for colorectal cancer. The quality of the procedure varies between centres and endoscopists. The aim of the present study was to describe a quality control programme for colonoscopy performance in a secondary care centre. MATERIAL AND METHODS: Starting in 2001, we established a systematic quality control programme. All patients received a questionnaire on their satisfaction with and pain during and after examination. The questionnaire was to be filled in the next day and mailed back to the centre. Pain and discomfort during and after colonoscopy and caecum intubation rate were registered as indicators of quality. RESULTS: During the study period of 15 month, 1354 colonoscopies were performed by 16 endoscopists. 94% of examinations were performed without any sedation. 1054 (78%) of patients responded to the questionnaire, 99% of whom were generally satisfied. The caecum intubation rate was 82%. While 23% of patients scored for moderate pain during the examination and 16% complained of severe pain, 61% had no or only light pain. Significant differences between endoscopists regarding pain and caecum intubation rate were found in a multiple logistic regression model. INTERPRETATION: A satisfactory feedback from patients was observed, with a high response rate to the questionnaire survey and high overall satisfaction, in spite of the fact that about one third of patients experienced moderate or severe pain. There were significant variations in performance between endoscopists.

Adolescent↗

New insight into the comparative power of quality-control rules that use control observations within a single analytical run.

The error detection characteristics of quality-control (QC) rules that use control observations within a single analytical run are investigated. Unlike the evaluation of QC rules that span multiple analytical runs, most of the fundamental results regarding the performance of QC rules applied within a single analytical run can be obtained from statistical theory, without the need for simulation studies. The case of two control observations per run is investigated for ease of graphical display, but the conclusions can be extended to more than two control observations per run. Results are summarized in a graphical format that offers many interesting insights into the relations among the various QC rules. The graphs provide heuristic support to the theoretical conclusions that no QC rule is best under all error conditions, but the multirule that combines the mean rule and a within-run standard deviation rule offers an attractive compromise.

Chemistry, Clinical↗

Randomized controlled multicentre evaluation of an education programme for insulin-treated diabetic patients: effects on metabolic control, quality of life, and costs of therapy.

A multicentre controlled randomized education study was performed to evaluate an education programme for insulin-treated diabetic patients. The main objective of the education programme, which took place on an out-patient basis, was to improve the level of self-care of the participants. Fifteen randomly recruited hospitals (558 patients) were equally divided into three groups: two experimental groups who completed the programme under the guidance of a health care professional or a fellow patient, and a control group. Patients in the experimental group were evaluated four times and those in the control group twice, with an intervening period of 6 to 7 months. The effect of the programme on metabolic control, quality of life, and costs of therapy was assessed. No significant effect of education of any one of these variables could be found.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Serum bactericidal testing with quality control organisms.

Measurements of serum bacteriostatic and bactericidal titers were compared using common quality control organisms. Oxacillin or vancomycin was added to normal sera for duplicate testing against Staphylococcus aureus ATCC 25923 while gentamicin or ampicillin was added for duplicate testing against Escherichia coli ATCC 25922. Recommendations of acceptable ranges are presented in the text. Establishment of acceptable ranges for serum bactericidal assay results could improve accuracy, allow comparisons of data from different studies and help reduce intralaboratory variations.

Anti-Bacterial Agents↗

Ofloxacin susceptibility testing quality control parameters for microdilution and disk diffusion, and confirmation of disk diffusion interpretive criteria.

The susceptibilities of 221 clinical isolates to ofloxacin were tested simultaneously by broth microdilution and disk diffusion methods with commercially prepared 5-micrograms ofloxacin disks. The acceptability of the following previously proposed zone diameter breakpoints was confirmed: greater than or equal to 16 mm, susceptible; 13 to 15 mm, intermediate; less than or equal to 12 mm, resistant. On the basis of a multilaboratory collaborative study, the following are proposed as acceptable ofloxacin MIC ranges for quality control organisms: Escherichia coli ATCC 25922, 0.03 to 0.06 micrograms/ml; Staphylococcus aureus ATCC 29213, 0.12 to 0.5 micrograms/ml; Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212, 1.0 to 4.0 micrograms/ml. Ofloxacin quality control zone diameter ranges for the disk diffusion test are tentatively proposed, but variations in the performance of different lots of Mueller-Hinton agar may prove to be a serious problem for users.

Bacteria↗

Maintaining continence in nursing home residents through the application of industrial quality control.

Supervisory nurses in seven nursing homes were taught how to implement a quality control management system that permitted the time-efficient assessment of how well a prompted voiding toileting program continued to be implemented by indigenous nursing aides. Random-hour wet checks taken during the 6-month management period revealed a reduction in wetness from 43% to 21% (p < .0001), which was sustained over the full 6-month period.

Aged↗

Quality-control scheme for blood glucose measured outside the laboratory.

We propose a quality-control (QC) scheme to evaluate the performance of blood glucose estimates made with a reflectometer in hospital wards or at home. We constructed a chart illustrating the comparison by regression analysis of the results of 254 reflectometer readings (y) and simultaneous capillary blood glucose analyses in the laboratory (x). Arbitrary acceptance limits around the regression line (y = 0.5 + 0.87x; r = 0.97, Sy/x = 0.8 mmol/L) were established, based on the mean +/- 2 SD of the reflectometer readings of a series of classes of 1.1 mmol/L interval, made with the results from the laboratory analyzer. Each ward using a reflectometer is provided with the QC chart, and the first blood glucose estimation with the reflectometer on each working shift is controlled by re-assay in the laboratory. If the reflectometer reading is outside the limits, the next glucose estimation is also re-assayed. If two consecutive readings are outside the limits, the reflectometer procedure is considered to be failing, the instrument's readings are not used for medical decisions, and remedial action is taken. The chart can also be used as a teaching tool for training the patients or the nurses and to evaluate individual performance.

Blood Glucose↗

The autopsy in clinical quality control.

The postmortem examination, despite declining rates, remains the final word in diagnostic quality control and a major tool in research and education. In 100 autopsies studied at our institution, it was found that 13% of major clinical diagnoses were not confirmed, and in 24% the cause of death was not in the clinical diagnoses. These figures demonstrate a higher clinical diagnostic accuracy rate than in previous studies, and the possible reasons for this are discussed. The length of hospital stay is not found to have any bearing on diagnostic accuracy.

Adult↗

[Quality controls for the gamma camera with single photon emission tomography].

Some tests and quality controls to assess the initial conditions and the working performance of a SPET system (Single Photon Emission Tomography), are described. Suitable tomographic phantoms were designed and built. We outline the methods to check MTF, stability of the photoelectric peak, centre of rotation, spatial uniformity, spatial resolution, sensitivity. NEMA tests should first be carried out to check the planar scintigraphic performance of the gamma-camera. This study allows to comprehensively evaluate the qualitative and quantitative performance of the SPET system and the correct check frequency of investigated parameters.

Quality Control↗

Quality control of scintillation cameras using a minicomputer.

A minicomputer-based technique compiles objective indicators of scintigraphic system performance. The evaluation begins with the acquisition of a single image of an orthogonal hole pattern from which quantitative and regional measurements of point-source sensitivity, spatial resolution, and spatial linearity are derived. Two computer programs offer the user different but complementary features. The first program is the basis of an evaluation performed by a technologist for purposes of quality control. Operator intervention is minimal, and the entire protocol, including data acquisition and processing, can be completed in 20 min. The results are automatically compiled and displayed as graphs showing 100 consecutive sets of daily performance measurements. A second computer program is designed as an interactive diagnostic and research tool to display measurements as histograms and functional images. The operator can use the program to determine the quantitative and spatial characteristics of the system's intrinsic performance measurements made during the quality-control evaluations.

Computers↗

Molecular quality control machinery contributes to the leukocyte NADPH oxidase deficiency in chronic granulomatous disease.

Chronic granulomatous disease (CGD) is an inherited immunodeficiency disease caused by defects in leukocyte NADPH oxidase. Various inherited defects in one of the membrane-bound components of NADPH oxidase, gp91-phox, cause X-linked (X91) CGD. Analysis of three patients with X91 CGD revealed that different mechanisms of molecular quality control lead to the common phenotype of absence of mature membrane-bound NADPH oxidase complex in leukocytes. In the first patient, aberrant intron splicing created a premature stop codon. However, the mutant mRNA was degraded prematurely, which prevented the production of truncated protein. In the second patient, a frameshift mutation with the potential to generate a gp91-phox polypeptide, with an aberrant and elongated C-terminus, led to barely detectable levels of gp91-phox, even though the reported functional domains of the protein appeared unaffected. In the third patient, a point mutation created a single amino acid change in the predicted FAD-binding site of gp91-phox. Although gp91-phox was detectable with Western blotting, no cytochrome b(558) was expressed on the cell surface. These analyses showed that molecular quality control machinery plays an important role in the pathogenesis of CGD, not only in the X910 but also in the X91- form of this X-linked disease.

Cell Membrane↗

Evaluation of quality control methods for medical documentation.

A retrospective study about the impact of different quality control methods for medical documentation was performed at the Surgical Center II in Essen. The standardized medical documentation was legislative obliged since the first of 1996 and includes diagnoses and surgical procedures. The patient data were taken from the computer-based patient record of the Surgical Center II which is in routine use since 1989. Quality improvement was aimed at with lectures, training, a quality circle, and systematic approaches like feedback and reminder between 1995 and 1996. The results demonstrate that information and training of physicians is significantly less important for the quality of documentation than a departmental and central control. It is advisable to take this results into account introducing new documentation entities and procedures and to provide functionalities for a periodical control soon.

Data Collection↗

Quality control of Cordyceps sinensis, a valued traditional Chinese medicine.

Cordyceps sinensis, a well-known and valued traditional Chinese medicine, is also called DongChongXiaCao (winter worm summer grass) in Chinese. It is commonly used to replenish the kidney and soothe the lung for the treatment of fatigue, night sweating, hyposexualities, hyperglycemia, hyperlipidemia, asthemia after severe illness, respiratory disease, renal dysfunction and renal failure, arrhythmias and other heart disease, and liver disease. As the rarity and upstanding curative effects of natural Cordyceps, several mycelial strains have been isolated from natural Cordyceps and manufactured in large quantities by fermentation technology, and they are commonly sold as health food products in Asia. In addition, some substitutes such as Cordyceps militaris also have been used and adulterants also confused the market. Therefore, quality control of C. sinensis and its products is very important to ensure their safety and efficacy. Herein, markers and analytical methods for quality control of Cordyceps were reviewed and discussed.

Amino Acids↗

Measurement of enzyme activity and substrates in intestinal mucosa. Evaluation of a system for quality control in clinical and experimental gastroenterology.

Widely used methods in diagnostical and experimental gastroenterology like measuring the protein-and DNA-content and the activity of alkaline phosphatase and sucrase of intestinal mucosa were adapted to a microliter system and partly automatized. With "artificial" control material a system for statistical quality control was established. Lastly the results on up to three years experience with this control system were presented showing an imprecision within run below 5% and an in-imprecision between run below 8% in all methods.

Alkaline Phosphatase↗

[External quality control system in medical microbiology and parasitology in the Czech Republic].

The External Quality Control System (EQAS) of laboratory activities in medical microbiology and parasitology was implemented in the Czech Republic in 1993 with coded sera samples for diagnosis of viral hepatitis and bacterial strains for identification distributed to first participating laboratories. The number of sample types reached 31 in 2003 and the number of participating laboratories rised from 79 in 1993 to 421 in 2003. As many as 15.130 samples were distributed to the participating laboratories in 2003. Currently, almost all microbiology and parasitology laboratories in the Czech Republic involved in examination of clinical material participate in the EQAS. Based on the 11-year experience gained with the EQAS in the Czech Republic, the following benefits were observed: higher accuracy of results in different tests, standardisation of methods and the use of most suitable test kits.

Czech Republic↗

Quality control of radiation therapy equipment.

A review is given dealing mainly with the quality control functional performance characteristics of medical electron accelerators as the leading case of all equipment for radiotherapy. The International Electrotechnical Commission (IEC) has prepared a standard and a report, which are now in print. The standard addresses the definition of functional performance characteristics, the specification of test methods and conditions and the obligation of the manufacturer to declare the actual performance values of his equipment in a standardized format. In Germany, a translation of this standard is published as draft standard DIN 6847 part 4. IEC has prepared for simplified test procedures a report with guidelines and a reduced volume of test conditions for periodic tests during the working life of the accelerator. In Germany a standard DIN 6847 part 5 is published on "constancy checks" which is slightly but characteristically different from the IEC Report. The differences are schematically listed and discussed.

Equipment Safety↗

Quality control of laboratory tests run in a neonatal intensive care unit.

We examined the accuracy of laboratory screening tests in eight neonatal intensive care units. Analytes were provided by the EXCEL proficiency testing program of the College of American Pathologists (CAP), Skokie, III, samples were analyzed for hematocrit values and urine specific gravity. "Dipstick" tests were also performed for urinary protein, bilirubin, blood, glucose, pH, and ketones. The one intensive care unit that adhered to a formal quality control program for all these tests uniformly reported results well within statistically acceptable limits as defined by CAP. The seven other centers reported 14 instances of results that were either greater than 1 SD of the mean or considered by the consensus method to be outside acceptable CAP limits. Three of these results may have led to inappropriate clinical action in neonates. We conclude that there is a real potential for errors to be made in screening tests run by nurses in a neonatal intensive care unit when a formalized quality control program is not in effect.

Clinical Laboratory Techniques↗