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PubMed1996

Screening for stereopsis without the use of technical equipment: scale development and cross-validation.

BACKGROUND: Although adequate stereopsis is important for many common sensory-motor activities, large-scale normative samples of the relationship between stereopsis and other individual difference variables are relatively scarce, and stereopsis is often not routinely tested even in settings where it might play an important role. This is, in part, due to the fact that data collection requires individual testing, the use of costly technical equipment and trained personnel. METHOD: Beginning with a pool of 161 items and an initial sample of 542 individuals, we developed a self-report inventory-suitable for group testing, survey administration or rapid individual screening--possessing a high correlation with laboratory measures of stereopsis. The inventory was then cross-validated against laboratory measures of stereo-acuity in a separate sample of 573 subjects. RESULTS: For the combined samples, the resulting 10-item Stereopsis Screening Inventory (SSI) correlated with laboratory measures of per cent stereopsis (r = 0.80). The inventory's reliability was assessed with a resulting internal consistency coefficient (alpha) of 0.88. CONCLUSIONS: The SSI provides a fast, valid and inexpensive measure of uncorrected stereopsis which can be used for rapid screening or epidemiological surveys. The correct classification rate for the SSI was 84% for a low fence requiring 65% stereopsis or better, and 81% for a high fence of residual stereopsis of 25% or less. A conversion equation, with inventory and scoring procedure is given in the Appendix.

Adolescent↗

PubMedDate not supplied

[Clinical examination of children in municipal pediatric polyclinics].

In 3 municipal polyclinics in city of Makhachkala, Republic of Dagestan, special research was carried out to elaborate technical guidelines enhancing quality of children clinical examinations. Quality of children clinical examinations had been assessed according to expert evaluation of 437 outpatient records. Expert appraisal revealed that in municipal pediatric polyclinics quality of children medical examinations didn't correspond the needed level. Irregular medical supervision of children by district pediatricians (23.1% of cases), district nurses (38%) and clinical specialists (68.3%) is established. It is noted that in 19.9% of cases untimely medical examinations were held. Moreover, for every forth patient the medical examination was incomplete. Health promoting activities (17.5%) and medical rehabilitation (24.8%) were carried out inadequately. On basis of research data system of actions enhancing quality of children medical examinations under municipal pediatric polyclinics practice is elaborated.

Ambulatory Care↗

PubMed1996

[Recent improvement of mammographic diagnosis].

The improvement of mammographic diagnosis consists of 3 factors as follows; (1) improvement of mammographic apparatus, (2) technical advancement on photographing and reading of mammograms, and (3) correlation between mammographic findings and pathology. Improvement of apparatus was achieved by molybdenum anode and faster single screen combined with a high-speed single-emulsion film combination system. These system provide the dose reduction as only one day reduction of the average future time if anyone take the mammographic screening of breast cancer once a year over 30 years old. These alterations of apparatus produced the mammograms darkers, and the intensity of illumination of the view system brighter. These some improvements of the mammography have made the mammograms to be very high quality. As natural consequence mammographic diagnosis has some new roles. Screening of the breast cancer is the most important one. The diagnosis the lesion cancer or not is very important, too. If the lesion was found only with mammography, the biopsy under mammographic guidance is necessary. And the diagnosis of the extension of the cancer lesion is very important for surgical treatment. If the lesion has fine calcifications, mammography can diagnose the extent very objectively.

Breast Neoplasms↗

PubMed1985

Screening for hematuria, glucosuria and proteinuria in people aged 55-64. Technical, clinical and cost-benefit experience from a pilot study.

A total of 754 persons randomly selected from the age group 55-64 years were invited by letter to take part in a screening for hematuria, proteinuria and glucosuria. Each person was asked to provide one sample of morning urine and immediately mail it to the laboratory. A total of 413 persons (55%) responded. Two dipsticks: BM-Test-5L and a new single strip for hematuria determination preliminary named BM 33075 were used, both manufactured by Boehringer Mannheim GmbH. The test strips gave positive reaction for hematuria in 21 persons (5.1%), for proteinuria in 14 persons (3.4%), and for glucosuria in six persons (1.5%). All persons with positive tests were invited to follow-up investigations. In the hematuria group we found one person with a malignant disease, 13 with benign conditions and in seven persons we found no reason for the hematuria. Among those with proteinuria one person had a nephritis. Four persons with glucosuria knew about their diabetes mellitus. The cost of the screening was NOK 99 per participant.

Cost-Benefit Analysis↗

PubMed2003

Evaluation of audiologic impairment in critically ill patients: results of a screening protocol.

OBJECTIVE: To assess hearing impairment in adults admitted to a university surgical intensive care unit in order to identify patients at risk for impaired receptive communication. DESIGN: Prospective, clinical, observational study within the continuing quality improvement program. SETTING: Ten-bed adult surgical intensive care unit at a university hospital. PATIENTS: Patients were 442 adult patients admitted to the surgical intensive care unit for trauma, a critical illness, or postoperative monitoring. INTERVENTIONS: As part of a continuing quality improvement protocol, adults admitted to the surgical intensive care unit were screened for hearing loss. Screening included otoscopy, tympanometry, and distortion product otoacoustic emissions as near the time of admission as was possible. Testing was available only on weekdays. MEASUREMENTS AND MAIN RESULTS: Audiologic testing was performed on day 1.7 +/- 3.0 and took 9.3 mins (range, 5-17 min). The women studied (n = 177, 56.2 +/- 18.2 yrs) were significantly older than the men (n = 265, 51.2 +/- 17.8 yrs, p <.0001). We found that 71.4% of patients had normal otoscopy. Only 42.5% of patients passed tympanometry. True failures accounted for 37.3% of patients and technical failures for 20.2%. Distortion product otoacoustic emission (DPOAE) testing was performed on 97.4% of ears. Only 36.2% of patients passed; 58.4% of ears failed, suggesting clinically significant auditory impairment. DPOAE results correlated with age. The pass rate was approximately 60% for patients <40 yrs of age but declined steadily by decade to <7% in patients >80 yrs. The mean age of passed DPOAE (44.2 +/- 16.2 yrs) was significantly younger than patients who failed DPOAE (60.0 +/- 16.6 yrs, p <.0001). CONCLUSIONS: Adult patients admitted to the surgical intensive care unit for trauma, postoperative monitoring, or critical illness are at significant risk of impaired auditory reception. Almost two thirds of patients studied failed the screening protocol. Risk of failure increases with age and male gender. Screening with otoscopy, tympanometry, and DPOAE is an efficient and sensitive way to identify patients at risk for impaired auditory acuity.

Acoustic Impedance Tests↗

PubMed1999

[Assessment of mammography screening and its introduction in Germany in the Statutory Early Diagnosis Program].

Malmö, in the south of Sweden, has, over the past 15 years, achieved a reduction in the mortality rate of 10% as a result of adjuvant drug treatment (adjuvant chemo- and hormone therapy). The drop in the mortality rate by means of a quality assured early diagnosis programme, reduces the mortality rate for breast cancer by 34% so that in South Sweden these methods have reduced the death rate for breast cancer by a total of 44% although the incident rate has increased by 1.25%. It follows that a quality assured early diagnosis programme is by far the most effective method of reducing the mortality rate for breast cancer, whereby breast cancer constitutes the main cause of death from cancer in women. The effectiveness of early diagnosis is dependent on experience with these methods whereby the learning curve, even in the case of specialists, does not reach a maximum until there has been at least 6-8 years experience and a minimum of 8000 patients have been seen. A reduction in the mortality rate can only be achieved if a large number of the population takes part (in Sweden, 89% of women contacted) and only applies to the age group 40-70. In the case of younger women (40-50 years) the reduction in the death rate in Sweden lies at 30%. For cost-benefit reasons this age group has not yet been recommended for routine screening in Sweden, apart from in clinical studies. Screening is only effective with complete quality control of technical equipment and personnel as stipulated in the European guidelines for screening mammography (August 1997 edition, EU Commission (EUREF). The risks of radiation exposure, with a threshold value of 5 mGy per breast (X-ray in two planes), is so minimal that it is as yet not measurable. The induction of breast cancer through annual screening mammography is estimated theoretically at 4 indicated cases of breast cancer to 1 million female years. Theoretically these induced cases of breast cancer can be cured by early diagnosis. A reduction in the mortality rate of 34% is a tremendous advantage for women. Since breast cancer is the main cause of death in women between the ages of 38 and 51 and screening considerably cheaper than other preventive measures (cervical smear, dialysis in kidney disease, safety belts, medication to lower cholesterol levels) the introduction of quality assured screening is an essential priority towards improving the health of women in society today. It has been proved (Netherlands) that the cost of screening is far lower than the expense incurred in the treatment of women in the metastatic stage of their cancer illness before death.

Adult↗

PubMed1975

Clinical genetics: some neglected facets.

Like general medicine, clinical genetics has responsibilities to research, to dissemination and to service. Each exists at three broad levels. The elemental comprises acquisition of fact and development of technics. At the intermediate level coherence becomes a major concern: the discernment of relations among facts; the incorporation of data into ideas and insights; organization of clinical findings into a diagnosis; and the development of the rational management. The sophisticated level calls for theories and cosmologies at the scientific level, and cultivation of scholarship and of clinical wisdom. All nine compartments should be mutually correcting. If any of them is neglected or isolated from the rest, the whole will be impoverished-the student will suffocate in disconnected, empirical facts; fanciful theories will be spun from tenuous evidence; well established theory will be neglected by the practitioner; the best-intentioned schemes will have disastrous long-term consequences.

Cytogenetics↗

PubMedDate not supplied

Flexible sigmoidoscopy as a screening test for colorectal cancer.

Flexible sigmoidoscopy (FS) is one of the screening modalities for colorectal cancer. The rationale for screening with flexible sigmoidoscopy is that it provides direct visualisation of the colon, and suspicious lesions can be biopsied. The most obvious disadvantage is that it examines only the lower third of the colon. The technical aspects of FS are sufficiently clear to enable us to define what FS can and cannot do. From the point of view of screening, FS clearly cannot completely exclude the presence of colon cancer in all asymptomatic people. A distinction must be made between screening the general population and testing the individual seeking screening. For the former, obtaining the greatest mortality benefit safely and at an acceptable cost to the nation is the crux of the matter. Recently published data indicate that FS is a cost-effective screening strategy, although colonoscopy and annual fecal occult blood test avert a greater number of cancer deaths. The results of randomised controlled trials of screening FS and colonoscopy, currently being conducted, will allow us to make a more accurate comparison with the established data regarding fecal occult blood test. In conclusion, flexible sigmoidoscopy every 5 years with or without FOBT is one of the screening methods recommended by major professional organizations. It identifies 50 to 70% of the advanced neoplasms, if any discovery of a distal neoplasia is followed up with a total examination of the colon by colonoscopy.

Age Factors↗

PubMedDate not supplied

Sucrose concentration in blood: a new method for assessment of gastric permeability in horses with gastric ulceration.

A urine sucrose test has recently been reported to be a reliable method of detecting gastric ulcers in horses; however, technical difficulties associated with urine collection have limited the practical value of the test. The objective of this pilot study was to determine whether gastric sucrose permeability, as evaluated by serum sucrose concentration, could be used to detect gastric mucosal injury in horses. Twelve adult horses with naturally acquired gastric ulceration were studied. After a 20-hour nonfeeding period, each horse was dosed with 250 g of sucrose via nasogastric intubation. Blood samples were collected at 0, 15, 30, 45, 60, and 90 minutes, and horses underwent gastroscopy 4 hours later. The severity of gastric ulceration in each horse was defined by means of a 4-point ulcer-scoring system, and the relationship with serum sucrose concentration was analyzed by means of a linear mixed-effects model. Serum sucrose concentration was measured by liquid chromatography operating in tandem with electrospray mass spectrometry. After nasogastric administration of table sugar, horses with moderate to severe gastric ulceration had significant increase in serum sucrose concentration at 30, 45, 60, and 90 minutes, relative to earlier times (P < .05). Peak sucrose concentration was observed at 45 minutes, and was correlated with ulcer severity (Spearman's rank correlation coefficient = 0.898, P < .05). These data indicate that determination of sucrose concentration in equine serum may be a useful test for identifying horses with endoscopically visible gastric ulceration and has potential use as a noninvasive method for screening and monitoring horses engaged in racing training and other performance-related disciplines.

Animals↗

PubMed2001

[Technical errors in the application of Graf's hip sonography method].

AIM: The aim of the study is to point out possible examination errors because of a titled transducer, and to analyse their sources. METHODS: The results obtained by experienced examiners using the correct examination technique were compared to results obtained under defined deviations from the standard. With the use of a computer model the course taken by the ultrasound waves in the neonatal hip was simulated and the sonographic image reconstructed. RESULTS: Twisted as well as tilted positions of the transducer lead to significant errors in alpha, the acetabular roof angle. This is in accordance with the computer model predictions. Caudo-cranially tilted probes lead to false-positive, therapeutically relevant incorrect diagnoses. CONCLUSION: The computer simulation predicts a high degree of accuracy of hip sonography in Graf's technique under standard conditions. The effectiveness of sonographic infant hip screening largely depends on the ability to adhere to the standardized approach, minimizing possible errors. A mechanical transducer guide prevents tilting errors by reducing the degrees of variability in positioning the transducer.

Artifacts↗

PubMedDate not supplied

Whose blood is safer? The effect of the stage of the epidemic on screening for HIV.

BACKGROUND: With improvements in HIV antibody test (ELISA) performance, the window of time between infection and seroconversion becomes a major source of error in HIV screening. The authors examined its impact on the false-reassurance rate (FRR). METHODS: Test sensitivity was modeled as the product of two factors: the inherent sensitivity (sensitivity when antibody is present) and the probability that antibody is present in infected blood. A model of HIV and AIDS incidence was used to derive an estimate of the probability of remaining in the seronegative window (pw) among those who are infected. With plausible assumptions, this probability approaches 0.03. The FRR was then estimated as a function of the probability of remaining in the seronegative window, the prevalence of HIV, and the inherent sensitivity of the ELISA test were estimated. RESULTS: The FRRs for two blood donor groups, one with an HIV prevalence of 0.004 and a typical probability of remaining in the seronegative window (pw = 0.03) and the other with a higher prevalence of 0.017 but fewer donors in the window (pw = 0.003), are equal (140 per million donors) if the blood is negative on a single ELISA test. After two negative tests or a single test that can detect antibody more reliably, however, the FRR is much higher in the group with the higher pw (= 120 per million compared with 50 per million), because the greater numbers of donors in the window more than offsets the lower prevalence. CONCLUSION: With improvements in inherent sensitivity of ELISA by virtue of technical progress or retesting, the prevalence of HIV infection may no longer play the critical role in degrading the results of blood screening. As inherent test performance improves, tests are increasingly likely to miss infected blood because of the seronegative-window error rather than because of measurement error. Window error plays a proportionally greater role during the early stages of HIV dissemination in a population where the incidence of new HIV infection is high relative to the incidence of AIDS. These findings may explain, in part, the recent observation that cases of transfusion of contaminated blood often take place in areas where AIDS epidemics have started recently. They also suggest that the traditional strategy of soliciting blood donors from low-prevalence populations may not always be optimal, unless such populations are truly low-risk.

Blood Banks↗

PubMed2005

Health information system for community-based multiple screening in Keelung, Taiwan (Keelung Community-based Integrated Screening No. 3).

BACKGROUND: Community-based multiple screening for common cancers and chronic diseases has increasingly gained attention. However, as infrastructure and evaluation system are more diversified and complicated compared with single screening, the development of a novel health information system is paramount. METHODS: The main goal of our health information system was to support the multiple screening program not only from technical aspect but also from a broad range of perspectives including quality assurance system, organized features appertaining to screening, economic evaluation (cost-effectiveness or cost-utility analysis), epidemiological applications, behavior risk factor surveillance system, and social impact due to the introduction of the Keelung Community-Based Integrated Screening (KCIS) program. RESULTS: Health information system was designed and programmed on the basis of the demand derived from KCIS within which five cancers and three chronic diseases were included. In addition to the detailed description of infrastructure and process, design, relevant database and security involved in health information system, an innovative and extensive evaluation system in accordance with the main goals was included in our health information system. CONCLUSION: Our information system proposed several aspects regarding organized screening system that has never been addressed in computerized system supporting for single screening. These included quality assurance system, organization features, co-morbidity profiles, epidemiological applications and social and economic considerations.

Community Health Services↗

PubMed1990

Controversies in transfusion medicine. Alanine aminotransferase screening of blood donors: pro.

In my opinion, independent, carefully conducted scientific studies indicate that an accurate, rapid, relatively sensitive, and inexpensive laboratory test substantially reduces the major long-term risk of blood transfusion in the United States; donor ALT has emerged as one of the most effective laboratory determinants for reducing the incidence of NANB PTH. Despite its nonspecificity and limited predictive value, ALT screening may prevent up to 30 percent of cases, one-half of which would progress to chronic liver disease and then possibly to cirrhosis and hepatocellular carcinoma. Blood donors appear to understand and accept the testing rationale as a reasonable precaution. Admittedly, ALT screening is not a perfect solution. It has not been validated by prospective studies and probably never will be. Determination of the proper cutoff value remains controversial. However, the risk of PTH progresses with increasing ALT levels, so that the real issue is not whether to test, but how best to configure the test to exclude the fewest false-positive donors while detecting the most true-positive donors. It is undesirable and expensive to discard safe units of blood, but the primary responsibility of blood collectors is to ensure an adequate supply of safe components. Some still consider the ALT assay technically too demanding for routine use. However, technical concerns regarding performance and interpretation are not insurmountable, and both quality control and proficiency testing are being addressed at the national level. The assay is capable of great precision, and a system employing a national standard and single cutoff has already been described and tested with excellent results. Circumstances have changed since donor screening with ALT was widely implemented in 1986. More thorough screening and testing have eliminated many high-risk donors. Public expectations have changed as well. While it is neither reasonable nor responsible to promise the public blood transfusions without risk, neither is it prudent to propose any major change in management of the blood supply without compelling evidence that such a change will not impair transfusion safety. It is hard to defend discontinuing the ALT screen at this time, especially when the costs of retaining it are minimal and the benefits clearly greater than those of screening for HTLV-I and for Treponema pallidum (in the United States) or HIV-2 (in West Germany). A first-generation assay specific for antibody to hepatitis C will probably be available within a year.(ABSTRACT TRUNCATED AT 400 WORDS)

Alanine Transaminase↗

PubMed2002

Evaluation of the lower spine after blunt trauma using abdominal computed tomographic scanning supplemented with lateral scanograms.

BACKGROUND: Patients at risk for thoracolumbar junction (TLJ) and lumbar spine (LS) injury after blunt trauma are classically evaluated using conventional radiographs. Frequently, these patients also undergo abdominal and pelvic computed tomographic (CT) scanning to exclude the presence of associated intra-abdominal injuries. Standard abdominal and pelvic CT scan usually includes an anteroposterior (AP) scout film (scanogram) obtained before the cross-sectional imaging. The objective of this study was to determine whether a lateral CT scanogram and axial CT views would provide adequate imaging to allow for evaluation of the TLJ and LS and therefore eliminate the need for conventional screening computed lumbar spine radiographs (CLSRs). METHODS: Patients who sustained blunt injury and required both CLSRs as well as abdominal and pelvic CT scans were prospectively identified. The study protocol (CT + S) added lateral CT scanograms to all helical abdominal and pelvic CT scan studies. The AP and lateral CT scanograms were included with the axial images, and these views were reviewed together during final radiographic interpretation and diagnosis. The results of CT + S were compared with readings of the CLSRs (AP and lateral) in a blinded fashion by a trauma radiologist. RESULTS: Lateral scanograms were generated for 71 patients. All scanograms were technically adequate, with image quality equal or superior to computed plain radiographs. Ten patients were found to have 20 fractures, 19 acute and 1 chronic. All abnormalities identified by plain radiographs were seen using CT + S (sensitivity, 100%; specificity, 100%). Eight transverse process and two spinous process fractures not seen on CLSRs were identified using CT + S. CONCLUSION: Our CT + S protocol (axial CT images plus AP and lateral scanograms) outperformed screening CLSRs in the detection of fractures of the lower spine (TLJ + LS) after blunt trauma. In addition, scanogram imaging is less dependent on body habitus and adds no additional cost or time to abdominal and pelvic CT scanning. Further study is required to determine whether CT + S can routinely replace conventional radiographs of the lower spine after blunt trauma.

Accidental Falls↗

PubMed1996

Plasma lysosomal glycohydrolases in a general population.

In this study we evaluated the differences in plasma levels of some glycohydrolases of lysosomal origin that appear to be the most interesting for possible usefulness for diagnosis (N-acetyl-beta-D-glucosaminidase, beta-D-glucuronidase, alpha-D-galactosidase, beta-D-galactosidase, alpha-L-fucosidase and alpha-D-mannosidase) in a general population of 417 subjects, as related to age and sex and also to body mass and to some habits, such as smoking and consumption of alcohol. The enzymatic activities were assayed by fluorimetric techniques with 4-methylumbelliferyl-glycosides as substrates. Particular attention was given to some technical aspects. Enzymatic activity was preserved by addition of ethylene glycol and stable liquid material was employed for calibration purposes. Blood was sampled rigorously at the same time of day and all the samples were obtained within a short period of time to exclude effects of the circadian and circannual rhythms. beta-Glucuronidase levels were the most affected by sex and body mass. beta-D-Galactosidase was not affected by differences in age, sex, body mass or by smoking, but appeared to be the most sensitive to modification by alcohol consumption. The data in this report emphasize that, whenever changes or differences in the levels of lysosomal enzymes in body fluids are studied, it is essential to have a reference population rigorously correlated with the study population. When possible, repetitive measurements in the same subject could better indicate a clinical trend.

Adult↗

PubMed1989

The occurrence of interval cancers in the Nijmegen screening programme.

Since January 1975 a population-based screening programme for the early detection of breast cancer has been carried out in the city of Nijmegen. During five interscreening periods of 2 years each a total of 158 so-called interval cancers were diagnosed. Careful revision of all screening and diagnostic mammograms was executed. Of all interval cancers 26% were 'missed' at the previous screening examination (due to technical or observer error), 16% were radiographically occult at the time of diagnosis and 58% were 'true' interval cancers. Interval cancers were regarded as 'true' when an obvious lesion was observed on the diagnostic mammogram while no suspect signs were seen on the previous screening mammogram. The prevalence of 'missed' cancers did not decline in the course of the screening programme. Radiographically occult tumours were localised, mostly in Wolfe's P2/DY breast parenchyma (83%), 33% were lobular invasive and 25% ductal non-invasive. 'True' interval cancer cases (58%) showed the same overall survival as control breast cancer patients, diagnosed in a non-screening situation. Shortening the screening interval would reduce interval cancer rates and probably further decrease breast cancer mortality in a screened population. However, from the present series of interval cancers 63% would not have been prevented by an annual screening examination. As regards women under age 50 annual screening would still leave 66% of all interval cancers in this age group undetected. Probably more benefit will be gained by searching for new imaging techniques to reduce numbers of 'missed' cancers and to detect lobular invasive and ductal non-invasive cancers in dense breast parenchyma.

Aged↗

PubMed2002

Hair analysis: another approach for the assessment of human exposure to selected persistent organochlorine pollutants.

Hair analysis was used for the assessment of exposure to organochlorine pollutants in specimens from Greece, Romania and Belgium. A simple method (using 3 N HCI as incubation reagent, liquid-liquid extraction with hexane/ dichloromethane (DCM), alumina/acid silica clean-up and GC-ECD/GC-MS analysis) was used for screening of specimens. The highest organochlorine load (up to 148 ng/g hair for the sum of PCB, DDT and hexachlorocyclohexane (HCH) isomers) was found in samples from a group of Greek women with past occupational exposure to pesticides. DDTs were the main organochlorine pollutants in Greek samples (up to 70%), while in Belgian hair samples their contribution was reduced to 40%. PCB mean concentration was higher in Belgian specimens (up to 14 ng/g hair). Lindane (y-HCH) was the main HCH isomer found in the samples (up to 82% in the Greek samples). Contribution of p,p'-DDT to the sum of DDTs was higher in Greek samples and indicates recent exposure to technical DDT. Similar PCB 153/sum PCBs ratios were found for each of the three countries suggesting similar sources of pollution with PCBs (mainly dietary). Artificially coloured hair samples were found to have lower, but not statistically significant concentrations of organochlorine pollutants than the non-coloured hair.

Age Factors↗

PubMed2001

Quality control of the physical and technical aspects of mammography in the Norwegian breast-screening programme.

The aim of this study was to establish a system for quality control of technical and physical aspects of mammography in the national Norwegian breast-screening programme, and to evaluate test results obtained during the 4-year pilot project period. Quality control (QC) procedures for the X-ray unit, film and processing, cassettes and screens, view boxes, and image quality were described in two QC manuals. Frequent and relatively simple tests were performed by radiographers on-site and results reported semi-annually to an inspection group established at the Norwegian Radiation Protection Authority (NRPA). Tests requiring special equipment were performed prior to start of screening (first status controls), then annually by the NRPA group, which also assembled and analysed the data from the first 4 years. The analyses were done mainly with reference to stated standard or guidance levels and the degree of deviation from such values. Results for tests of i.a. focal spot size, exposure time, radiation output, mean absorbed glandular dose, reference optical density, sensitometry, and AEC performance are presented. The standard of the equipment tested was in general high. Although some deviations from optimal performance were seen throughout the project, the equipment mostly performed well within the stated limiting values.

Aged↗