V

V. Fidler

Centraal Bureau voor de Statistiek

Publishes on Sepsis Diagnosis and Treatment, Neonatal and fetal brain pathology, Statistical Methods in Clinical Trials. 146 papers and 8.8k citations.

146Publications
8.8kTotal Citations

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Urinary Albumin Excretion Predicts Cardiovascular and Noncardiovascular Mortality in General Population
Cited by 1.5kOpen Access

BACKGROUND: For the general population, the clinical relevance of an increased urinary albumin excretion rate is still debated. Therefore, we examined the relationship between urinary albumin excretion and all-cause mortality and mortality caused by cardiovascular (CV) disease and non-CV disease in the general population. METHODS AND RESULTS: In the period 1997 to 1998, all inhabitants of the city of Groningen, the Netherlands, aged between 28 and 75 years (n=85 421) were sent a postal questionnaire collecting information about risk factors for CV disease and CV morbidity and a vial to collect an early morning urine sample for measurement of urinary albumin concentration (UAC). The vital status of the cohort was subsequently obtained from the municipal register, and the cause of death was obtained from the Central Bureau of Statistics. Of these 85 421 subjects, 40 856 (47.8%) responded, and 40 548 could be included in the analysis. During a median follow-up period of 961 days (maximum 1139 days), 516 deaths with known cause were recorded. We found a positive dose-response relationship between increasing UAC and mortality. A higher UAC increased the risk of both CV and non-CV death after adjustment for other well-recognized CV risk factors, with the increase being significantly higher for CV mortality than for non-CV mortality (P=0.014). A 2-fold increase in UAC was associated with a relative risk of 1.29 for CV mortality (95% CI 1.18 to 1.40) and 1.12 (95% CI 1.04 to 1.21) for non-CV mortality. CONCLUSIONS: Urinary albumin excretion is a predictor of all-cause mortality in the general population. The excess risk was more attributable to death from CV causes, independent of the effects of other CV risk factors, and the relationship was already apparent at levels of albuminuria currently considered to be normal.

Preoperative Staging of Non–Small-Cell Lung Cancer with Positron-Emission Tomography
Remge M. Pieterman, John W.G. van Putten, J. J. Meuzelaar et al.|New England Journal of Medicine|2000
Cited by 1.1kOpen Access

BACKGROUND: Determining the stage of non-small-cell lung cancer often requires multiple preoperative tests and invasive procedures. Whole-body positron-emission tomography (PET) may simplify and improve the evaluation of patients with this tumor. METHODS: We prospectively compared the ability of a standard approach to staging (computed tomography [CT], ultrasonography, bone scanning, and, when indicated, needle biopsies) and one involving PET to detect metastases in mediastinal lymph nodes and at distant sites in 102 patients with resectable non-small-cell lung cancer. The presence of mediastinal metastatic disease was confirmed histopathologically. Distant metastases that were detected by PET were further evaluated by standard imaging tests and biopsies. Patients were followed postoperatively for six months by standard methods to detect occult metastases. Logistic-regression analysis was used to evaluate the ability of PET and CT to identify malignant mediastinal lymph nodes. RESULTS: The sensitivity and specificity of PET for the detection of mediastinal metastases were 91 percent (95 percent confidence interval, 81 to 100 percent) and 86 percent (95 percent confidence interval, 78 to 94 percent), respectively. The corresponding values for CT were 75 percent (95 percent confidence interval, 60 to 90 percent) and 66 percent (95 percent confidence interval, 55 to 77 percent). When the results of PET and CT were adjusted for each other, only PET results were positively correlated with the histopathological findings in mediastinal lymph nodes (P<0.001). PET identified distant metastases that had not been found by standard methods in 11 of 102 patients. The sensitivity and specificity of PET for the detection of both mediastinal and distant metastatic disease were 95 percent (95 percent confidence interval, 88 to 100 percent) and 83 percent (95 percent confidence interval, 74 to 92 percent), respectively. The use of PET to identify the stage of the disease resulted in a different stage from the one determined by standard methods in 62 patients: the stage was lowered in 20 and raised in 42. CONCLUSIONS: PET improves the rate of detection of local and distant metastases in patients with non-small-cell lung cancer.

Faecal calprotectin for screening of patients with suspected inflammatory bowel disease: diagnostic meta-analysis
Cited by 711Open Access

OBJECTIVE: To evaluate whether including a test for faecal calprotectin, a sensitive marker of intestinal inflammation, in the investigation of suspected inflammatory bowel disease reduces the number of unnecessary endoscopic procedures. DESIGN: Meta-analysis of diagnostic accuracy studies. DATA SOURCES: Studies published in Medline and Embase up to October 2009. Interventions reviewed Measurement of faecal calprotectin level (index test) compared with endoscopy and histopathology of segmental biopsy samples (reference standard). Inclusion criteria Studies that had collected data prospectively in patients with suspected inflammatory bowel disease and allowed for construction of a two by two table. For each study, sensitivity and specificity of faecal calprotectin were analysed as bivariate data to account for a possible negative correlation within studies. RESULTS: 13 studies were included: six in adults (n=670), seven in children and teenagers (n=371). Inflammatory bowel disease was confirmed by endoscopy in 32% (n=215) of the adults and 61% (n=226) of the children and teenagers. In the studies of adults, the pooled sensitivity and pooled specificity of calprotectin was 0.93 (95% confidence interval 0.85 to 0.97) and 0.96 (0.79 to 0.99) and in the studies of children and teenagers was 0.92 (0.84 to 0.96) and 0.76 (0.62 to 0.86). The lower specificity in the studies of children and teenagers was significantly different from that in the studies of adults (P=0.048). Screening by measuring faecal calprotectin levels would result in a 67% reduction in the number of adults requiring endoscopy. Three of 33 adults who undergo endoscopy will not have inflammatory bowel disease but may have a different condition for which endoscopy is inevitable. The downside of this screening strategy is delayed diagnosis in 6% of adults because of a false negative test result. In the population of children and teenagers, 65 instead of 100 would undergo endoscopy. Nine of them will not have inflammatory bowel disease, and diagnosis will be delayed in 8% of the affected children. CONCLUSION: Testing for faecal calprotectin is a useful screening tool for identifying patients who are most likely to need endoscopy for suspected inflammatory bowel disease. The discriminative power to safely exclude inflammatory bowel disease was significantly better in studies of adults than in studies of children.