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The hypothesis that proximity to the Sun causes variation of decay constants at permille level has been tested and disproved. Repeated activity measurements of mono-radionuclide sources were performed over periods from 200 days up to four decades at 14 laboratories across the globe. Residuals from the exponential nuclear decay curves were inspected for annual oscillations. Systematic deviations from a purely exponential decay curve differ from one data set to another and are attributable to instabilities in the instrumentation and measurement conditions. The most stable activity measurements of alpha, beta-minus, electron capture, and beta-plus decaying sources set an upper limit of 0.0006% to 0.008% to the amplitude of annual oscillations in the decay rate. Oscillations in phase with Earth's orbital distance to the Sun could not be observed within a 10-6 to 10-5 range of precision. There are also no apparent modulations over periods of weeks or months. Consequently, there is no indication of a natural impediment against sub-permille accuracy in half-life determinations, renormalisation of activity to a distant reference date, application of nuclear dating for archaeology, geo- and cosmochronology, nor in establishing the SI unit becquerel and seeking international equivalence of activity standards.
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PURPOSE: This article provides an overview of the implications for patients' health status and care needs when assessments are performed by nurses not licensed or competent to perform this task. The Waterlow scale (Judy Waterlow, The Nook, Stroke Road, Henlade, TAUNTON, TA3 5LX) scenario is used as a practice example to illustrate this case. ORGANIZATIONAL CONSTRUCT: The international nursing regulatory bodies, in South Africa called the South African Nursing Council, set the scope of practice wherein nurses are allowed to practice. Different categories of nurses are allowed to practice according to specified competencies, in alignment with their scope of practice. METHODS: A retrospective quantitative study was utilized. A checklist was used to perform an audit on a random sample of 157 out of an accessible population of 849 patient files. Data were gathered in May 2012, and the analysis was done using frequencies and percentages for categorical data. Reliability and validity were ensured, and all ethical principles were adhered to. FINDINGS: Eighty percent of risk assessments were performed by nurses not licensed or enrolled to perform this task unsupervised. Areas such as tissue malnutrition, neurological deficits, and medication were inaccurately scored, resulting in 50% of the Waterlow risk-assessment scales, as an example, being incorrectly interpreted. This has implications for quality nursing care and might put the patient and the institution at risk. CONCLUSIONS: Lower-category nurses and student nurses should be allowed to perform only tasks within their scope of practice for which they are licensed or enrolled. Nurses with limited formal theoretical training are not adequately prepared to perform tasks unsupervised, even in the current global nursing shortage scenario. CLINICAL RELEVANCE: To optimize and ensure safe and quality patient care, risk assessments should be done by a registered professional nurse, who will then coordinate the nursing care of the patient with the assistance of the lower category of nurses.
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Competencia Clínica/normas , Atención de Enfermería/normas , Pautas de la Práctica en Enfermería , Calidad de la Atención de Salud , Necesidades y Demandas de Servicios de Salud , Humanos , Investigación en Evaluación de Enfermería , Seguridad del Paciente , Pautas de la Práctica en Enfermería/legislación & jurisprudencia , Estudios Retrospectivos , Medición de Riesgo , SudáfricaRESUMEN
This article evaluates the performance of 10 large scale upflow anaerobic sludge blanket (UASB) sewage treatment plants (STP) located in semi-tropical areas, 7 plants were located in Brazil, 2 in India and 1 in the Middle East. In addition to the UASB, essential functional units of the STP which potentially impact on the UASB are also evaluated. Most grit removal systems were performing adequately, however in one plant very little grit was being removed. This could have serious implications for the performance of the plant as in a relatively short period of time the reactors could become full of grit. The performance results obtained in this study (COD, BOD and TSS removal efficiencies) are compared to the results of recent literature publications and also to the results of some early pilot and full scale studies. The results found here are broadly similar to those result reported in the recent literature but show a lower performance in comparison with the early pilot scale plants. Factors such as improper design, poor operating procedures, insufficient maintenance and the presence of high sulphate concentrations have been identified as the main reasons for the lower performance.
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Aguas del Alcantarillado , Contaminantes del Agua/análisis , Anaerobiosis , Medio Oriente , Proyectos PilotoRESUMEN
At the National Metrology Institute of South Africa (NMISA) absolute activity measurements of γ-emitting radionuclides are maintained for longevity on a secondary standard ionization chamber. Because the ionization chamber has lower gas pressure than that normally produced by the manufacturer, this paper focuses attention on explaining a normalization scheme devised to allow NMISA to make use of the manufacturer's supplied radionuclide calibration factors when necessary. The applicability of the procedure is justified through analysis of some results from a comprehensive simulation of the chamber undertaken in an independent study. Comparisons of the derived normalized calibration factors against those obtained through measurement at NMISA are made for a variety of radionuclides.
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BACKGROUND: The diagnosis of atopic dermatitis (AD) is made using evaluated clinical criteria. Management of AD must consider the symptomatic variability of the disease. METHODS: EADV eczema task force developed its guideline for atopic dermatitis diagnosis and treatment based on literature review and repeated consenting group discussions. RESULTS AND DISCUSSION: Basic therapy relies on hydrating topical treatment and avoidance of specific and unspecific provocation factors. Anti-inflammatory treatment based on topical glucocorticosteroids and topical calcineurin antagonists is used for exacerbation management and more recently for proactive therapy in selected cases. Topical corticosteroids remain the mainstay of therapy, but the topical calcineurin inhibitors, tacrolimus and pimecrolimus are preferred in certain locations. Systemic anti-inflammatory treatment is an option for severe refractory cases. Microbial colonization and superinfection may induce disease exacerbation and can justify additional antimicrobial/antiseptic treatment. Systemic antihistamines (H1) can relieve pruritus, but do not have sufficient effect on eczema. Adjuvant therapy includes UV irradiation preferably of UVA1 wavelength or UVB 311 nm. Dietary recommendations should be specific and given only in diagnosed individual food allergy. Allergen-specific immunotherapy to aeroallergens may be useful in selected cases. Stress-induced exacerbations may make psychosomatic counselling recommendable. 'Eczema school' educational programmes have been proven to be helpful.
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Dermatitis Atópica/diagnóstico , Dermatitis Atópica/terapia , Dermatología , Eccema/diagnóstico , Eccema/terapia , Publicaciones Periódicas como Asunto , Guías de Práctica Clínica como Asunto/normas , Antibacterianos/uso terapéutico , Fármacos Dermatológicos/uso terapéutico , Diagnóstico Diferencial , Antagonistas de los Receptores Histamínicos/uso terapéutico , Humanos , Fototerapia/métodosRESUMEN
BACKGROUND: Multislice computed tomographic angiography (MCTA) has become the method of choice to screen for arterial injury in penetrating cervical trauma (PCT). There is, however, limited knowledge on its accuracy in terms of digestive tract injury (DTI). Currently, our unit liberally employs both computed tomographic angiography (CTA) and contrast swallow for platysma breaching penetrating neck injuries. This study aimed to determine the accuracy of specific computed tomography findings in the diagnosis of DTI after PCT. METHODS: This was a retrospective review of all consecutive patients with PCT who had undergone MCTA that presented at a single, tertiary, high-volume trauma centre from January 2013 until December 2015. Blinded radiological review of 140 MCTA investigations (33 in the injury group and 107 in the control group) was performed in order to calculate the diagnostic accuracy of trajectory, air, and conventional MCTA signs in the diagnosis of DTI after PCT. RESULTS: Over the study period, 906 patients presenting with PCT had undergone MCTA and a total of 33 patients (3.6%) had confirmed DTI on aggregate gold standard of diagnosis. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of MCTA for detecting DTI was 100%, 65.4%, 47.1%, and 100%, respectively. No injuries were missed on MCTA. CONCLUSION: Our findings suggest that DTI can be safely excluded by means of careful assessment of specific signs on CTA in patients presenting after PCT, obviating the need for further investigation.
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Angiografía , Heridas Penetrantes , Tracto Gastrointestinal , Humanos , Estudios Retrospectivos , Sensibilidad y Especificidad , Heridas Penetrantes/diagnóstico por imagenRESUMEN
The absolute activity of 18F was determined using 4πß-γ liquid scintillation coincidence counting using beta-efficiency extrapolation. An ionization chamber factor was determined for use during a SIRTI comparison, for which results are presented. A non-extrapolation method based on a detection efficiency analysis was also employed using an adaptation of the double-phototube coincidence efficiency for a threshold above the second monopeak. Results and uncertainty budgets for the two methods are presented and discussed.
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BACKGROUND: In South Africa, 42.0% of adult females and 13.5% of adult males are classified as obese, the highest recorded numbers in Sub-Saharan Africa. Metabolic surgery has been proven to be a safe and effective treatment, yet due to demand on government resources has only been performed to a limited extent in public hospitals. The aim of this study was to describe the safety and efficacy of performing metabolic surgery at a single academic hospital in South Africa. METHOD: This was a single centre retrospective review of 57 metabolic surgery procedures performed from October 2011 to September 2017 at Tygerberg Hospital, Cape Town, South Africa. The primary outcome was safety including mortality and adverse events. Secondary outcomes included effect of surgery on weight and diabetes resolution. RESULTS: A total of 57 patients underwent laparoscopic metabolic surgery, of which 44 (83.0%) were female with a mean age (standard deviation) of 42.8 (8.0) years. Fifty-six patients (98%) underwent Roux-and-Y gastric bypass and one (2%) had a sleeve gastrectomy performed. There were no mortalities and overall morbidity was 14.0%, with 3 (5.3%) classified as major and 5 (8.8%) as minor. The follow-up rate at 1 year was 100%. Mean preoperative body mass index (BMI) was 58.8 kg/m2, and comorbidities included hypertension (59.6%), Type 2 Diabetes (42.1%), and dyslipidaemia (36.8%). There were no conversions to open surgery and at one year the mean (95% confidence interval) percentage excess body mass index loss was 50.4% (44.0-56.8%). CONCLUSION: Metabolic surgery can be performed safely in the public sector in South Africa, with short-term safety and efficacy outcomes comparable to international reports. Larger scale studies are needed to determine long-term outcomes and cost-effectiveness.
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Cirugía Bariátrica , Obesidad Mórbida/cirugía , Adulto , Índice de Masa Corporal , Comorbilidad , Femenino , Humanos , Masculino , Obesidad Mórbida/epidemiología , Sudáfrica/epidemiologíaRESUMEN
Erlotinib is a small molecule tyrosine kinase inhibitor that is used as an anticancer agent. Most patients develop a pustular facial dermatitis within the first week of treatment. Pyogenic granulomas of the nail folds are another typical adverse event occurring in about 10-15% of cases. We report on a patient who developed a generalized dermatitis characterized by neutrophilic spongiosis. Neutrophilic inflammation has been observed in several drugs that interfere with EGFR signaling, suggesting a class effect. The present case may be yet another manifestation of this particular reaction pattern.
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Antineoplásicos/efectos adversos , Dermatitis/etiología , Erupciones por Medicamentos/etiología , Inhibidores de Proteínas Quinasas/efectos adversos , Quinazolinas/efectos adversos , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/secundario , Dermatitis/patología , Erupciones por Medicamentos/patología , Receptores ErbB/antagonistas & inhibidores , Clorhidrato de Erlotinib , Femenino , Humanos , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Persona de Mediana Edad , Neutrófilos , Piel/patologíaRESUMEN
Sirolimus is an immunosuppressive macrolide with antineoplasic properties that is increasingly used in posttransplantation immunosuppression. The treatment is frequently associated with cutaneous side effects such as sirolimus-associated acneiform facial dermatitis, which has been observed in up to 50% of treated patients. We report a 51-year-old female with liver transplantation who developed inflammatory papules and nodules on the face and the upper chest 3 weeks after the initiation of sirolimus therapy. Sequential biopsies revealed lymphocytic infiltration of the dermis with a peculiar pattern of sebotropism, while older lesions showed acquired reactive perforating collagenosis. The lesions were responsive to hydroxychloroquine treatment despite continued sirolimus treatment.
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Erupciones Acneiformes/inducido químicamente , Enfermedades del Colágeno/inducido químicamente , Erupciones por Medicamentos/etiología , Inmunosupresores/efectos adversos , Sirolimus/efectos adversos , Erupciones Acneiformes/tratamiento farmacológico , Erupciones Acneiformes/patología , Antiinflamatorios/uso terapéutico , Colágeno/análisis , Enfermedades del Colágeno/tratamiento farmacológico , Enfermedades del Colágeno/patología , Femenino , Humanos , Hidroxicloroquina/uso terapéutico , Trasplante de Hígado , Persona de Mediana Edad , Glándulas Sebáceas/patología , Sebo/química , Sirolimus/farmacocinética , Piel/patologíaRESUMEN
The radionuclides 99mTc and 57Co were standardized via absolute liquid scintillation counting techniques. We provide the first technical report on the absolute standardization of 99mTc using 4π(LS)e-γ coincidence counting. The low detection efficiency of low-energy conversion electrons translates into a large efficiency extrapolation range. A simulation indicated that the γ-ray interacting with the liquid scintillator introduces curvature to the count rate vs. efficiency relationship, the approximation of the functional form used for extrapolation providing the main measurement uncertainty for 99mTc. A detection efficiency analysis for both radionuclides is presented. Results from the standardizations, and SIRTI and SIR comparison exercises are reported.
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The 14-year follow-up mortality results from the randomized breast cancer screening trial of the Health Insurance Plan of Greater New York (HIP) were analyzed with respect to the problem of age-specific screening effects. Mortality reduction was measured in three different ways and appears to be homogeneous across age groups. This finding challenges the widespread opinion that the results of the HIP study support the conclusion that breast cancer screening is not effective below age 50.
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Neoplasias de la Mama/mortalidad , Tamizaje Masivo , Adulto , Factores de Edad , Neoplasias de la Mama/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , New YorkRESUMEN
Telomerase activation plays a crucial role in the immortalization of human cells and carcinogenesis; however, the temporal and pathophysiological aspects of the activation in vivo are poorly understood. We found telomerase activity not only in malignant tumors (91%) but also in most benign (60%) and premalignant (89%) skin tumors. This suggests the involvement of telomerase activation in a crucial biological step of human skin carcinogenesis. Because UV light is a major factor in skin carcinogenesis, we further examined telomerase activity in normal skin samples and in normal skin samples adjacent to benign, premalignant, and malignant skin lesions. Data for chronically sun-exposed body sites were compared with those for covered sites. Among normal skin samples, 39% (26 of 67) had telomerase activity, and this activity was unrelated to neighboring lesions but strongly associated with the level of sun exposure. Fifty-four % (21 of 39) of normal skin samples from chronically sun-exposed sites were telomerase-positive, compared with only 12% (3 of 26) of samples from covered sites. When we examined telomerase activity and CC to TT mutations at codons 247/8 of the p53 gene (which are considered to be UV specific) in the same normal skin samples, only 43% (7 of 16) of telomerase-positive normal skin samples at sun-exposed sites contained the p53 mutations, whereas all (7 of 7) of the samples with UV-specific p53 mutations showed telomerase activity (P = 0.019). These data suggest that telomerase activation is involved at an early stage of human skin carcinogenesis and that activation may precede the acquisition of UV-associated p53 mutations in the skin. Telomerase activity was also found in plucked hair follicles and enzymatically separated epidermis, which may be associated with the presence of stem cells in the skin.
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Neoplasias Inducidas por Radiación/etiología , Neoplasias Cutáneas/etiología , Piel/efectos de la radiación , Telomerasa/metabolismo , Activación Enzimática/efectos de la radiación , Femenino , Genes p53 , Folículo Piloso/enzimología , Humanos , Masculino , Mutación , Neoplasias Inducidas por Radiación/enzimología , Lesiones Precancerosas/enzimología , Piel/enzimología , Neoplasias Cutáneas/enzimología , Luz Solar , Rayos UltravioletaRESUMEN
This paper reports on absolute activity measurements of iron-59 made at the National Metrology Institute of South Africa (NMISA) via 4π(LS)ß-γ coincidence counting. The exercise formed part of an Asia Pacific Metrology Program (APMP) regional key comparison. Source data were analysed by the extrapolation technique for a number of gamma-ray window settings. In addition, a feasibility study was undertaken on a second technique; a non-extrapolation method based on a detection efficiency analysis. The reported activity concentration of the (59)Fe solution was determined with a relative uncertainty of 0.28% (k=1), the uncertainty being due mainly to the rate vs. efficiency fitting process. The result from the non-extrapolation method was lower than that given by extrapolation by 0.33%, within two standard deviations. Possible reasons for the small discrepancy are discussed.
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Atopic dermatitis (AD) is a chronic disease frequent in childhood. The treatment is based on regular moisturizing of the skin, information to the parents on the chronic course with recurrent flares, topical anti-infectious therapy for superinfections and colonization of the skin by staphylococcus aureus, and topical steroids. The immuno-modulatory macrolides (tacrolimus and pimecrolimus) represent a new alternative to topical steroids. These molecules are well tolerated, but theirs effects on the long-term are unknown. A food allergy may be responsible for a AD flare in up to a third of the cases, but the presence of an allergy should be demonstrated before the prescription of an elimination diet. AD is often the first manifestation of atopy: the physician should be aware of the future occurence of respiratory symptoms.
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Dermatitis Atópica/terapia , Corticoesteroides/uso terapéutico , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/etiología , Emolientes/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Padres/psicología , Cooperación del Paciente , PronósticoRESUMEN
Mutations in the p53 tumor suppressor gene are a common finding in many human malignancies. These mutations have been shown to inactivate the p53 protein and sometimes confer an oncogenic potential to the mutated gene. Type and pattern of p53 mutations may give clues to the tumor etiology, for example, ultraviolet-induced CC-->TT and C-->T transitions. Genomic DNA of 16 primary cutaneous melanomas of the superficial and nodular subtype and six melanoma metastases were screened for the presence of mutations in exons 5 to 8 of the p53 tumor suppressor gene, using the polymerase chain reaction and single-strand conformation polymorphism analysis, followed by direct DNA sequencing. We detected no mutations in any of the primary and metastatic melanomas in exons 5 to 8 of the p53 tumor suppressor gene. This indicates that, in contrast to skin carcinomas, p53 mutations are not operative in the evolution of human melanoma.
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Genes p53 , Melanoma/genética , Mutación , Neoplasias Cutáneas/genética , Secuencia de Bases , Carcinoma de Células Escamosas/genética , Exones , Humanos , Datos de Secuencia Molecular , Metástasis de la Neoplasia/genética , Reacción en Cadena de la Polimerasa , Análisis de Secuencia , Rayos UltravioletaRESUMEN
The cases of two young male siblings independently developing unilateral Wilms' tumors and brain tumors are reported. The renal tumors were resected; the first child was treated with chemotherapy and the second child was given additional radiotherapy. Five years after treatment, both children developed a second primary neuroectodermal tumor. All four tumors showed a high proliferative activity, and rapidly progressing disease led to the death of the first child. Histopathological and molecular studies were carried out on all four neoplasms. No functionally relevant mutation was found in selected exons of the p53, K-ras and WT1 gene loci of tumor and germ line DNA. Since additional family members had developed brain tumors and carcinomas, this peculiar association of neoplasms may be due to germ line mutation of a hitherto unidentified oncogene acting in a recessive or weakly dominant fashion.
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Neoplasias Encefálicas/genética , Glioma/genética , Neoplasias Renales/genética , Neoplasias Primarias Secundarias/genética , Tumor de Wilms/genética , Secuencia de Bases , Neoplasias Encefálicas/patología , Preescolar , Genes del Tumor de Wilms/genética , Genes p53/genética , Genes ras/genética , Glioma/patología , Humanos , Inmunohistoquímica , Neoplasias Renales/patología , Imagen por Resonancia Magnética , Masculino , Datos de Secuencia Molecular , Neoplasias Primarias Secundarias/patología , Linaje , Reacción en Cadena de la Polimerasa , Tumor de Wilms/patologíaRESUMEN
This report describes clinical, neuropathological and molecular genetic findings in a Swiss family with four brain tumours in only two generations. The neoplasms observed covered a wide range of biologic behaviour, from a slowly growing lesion already apparent at birth, to anaplastic astrocytoma in a young adult and glioblastomas at the age of less than 10 years. The only non-neural neoplasms in this family were a case of leukemia and an adrenocortical carcinoma. A germline deletion of codon 236 of the p53 tumour suppressor gene was identified as an underlying cause and detected in all affected family members. This mutation has not previously been reported as germline transmission or in sporadic tumours. The unusual accumulation of CNS tumours may be due to a certain organ-specific effect of this particular p53 mutation or it may reflect the specific genetic back-ground of this family.
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Neoplasias Encefálicas/genética , Genes p53 , Mutación de Línea Germinal , Eliminación de Secuencia , Adulto , Anciano , Secuencia de Bases , Neoplasias Encefálicas/patología , Niño , Preescolar , Codón , Femenino , Humanos , Inmunohistoquímica , Masculino , Datos de Secuencia Molecular , Linaje , Reacción en Cadena de la PolimerasaRESUMEN
BACKGROUND: Peripheral and tissue eosinophilia are associated with a group of idiopathic inflammatory syndromes. The idiopathic hypereosinophilic syndrome represents a spectrum of disorders characterized by prolonged eosinophilia of an undetectable cause and significant organ dysfunction. The pathogenic role of the eosinophil in these conditions is attested to by evidence of eosinophil activation and degranulation at sites of tissue injury. Recently, an overlapping range of idiopathic eosinophilic muscle disease with an overall good prognosis has been described. RESULTS: We describe a patient with a syndrome of idiopathic myositis with eosinophilia and eosinophilic cellulitislike cutaneous manifestations. Histopathological studies of the skin and muscle revealed eosinophilic infiltration. Elevated serum levels of eosinophilic cationic protein and interleukin-5 paralleling disease activity were detected. CONCLUSIONS: This patient demonstrates clinical and laboratory features of eosinophilic myositis with eosinophilic cellulitislike skin lesions. The elevated serum levels of interleukin-5 and eosinophilic cationic protein may be responsible for the eosinophilia and tissue injury, respectively. With the advances in our understanding of cytokine-dependent regulatory mechanisms governing the eosinophil reaction, more targeted ways of manipulating eosinophilia as well as the entry and activation of eosinophils within specific tissues can be expected.
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Proteínas Sanguíneas/análisis , Eosinófilos , Síndrome Hipereosinofílico/sangre , Interleucina-5/sangre , Miositis/sangre , Ribonucleasas , Enfermedades de la Piel/sangre , Adulto , Proteínas en los Gránulos del Eosinófilo , Femenino , HumanosRESUMEN
A mass screening programme for cervical cancer is in progress in three pilot regions in The Netherlands. All women living in these regions aged 35-53 are invited to undergo screening at three-year intervals. The MISCAN simulation model was developed for the analysis and optimization of screening programmes. In this paper the model-based approach to evaluation is first outlined and then illustrated by analysing data from the first two screening rounds in the pilot regions. This analysis resulted in a rather restricted range of data-compatible assumptions for the mean duration of preclinical disease (14-19 yr) and the frequency of spontaneous regression of preinvasive lesions (45-65%), as well as a rather wide sensitivity range for the Pap smear (50-90%). These preliminary findings are compared with those of a previous MISCAN analysis of cervical cancer screening in British Columbia. On the basis of an assumed 18-yr duration, 50% regression and 70% sensitivity, a number of screening policies relating to the same age ranges but with different intervals are compared. Both the analysis and the policy comparisons are preliminary, but the findings are nevertheless reasonable and consistent with those of previous studies. A more complete MISCAN-based analysis of the Dutch screening programme and subsequent optimization of screening policies will be possible when further results become available and a cost-effectiveness analysis procedure has been incorporated into the MISCAN programme.