Nederlands tijdschrift voor geneeskunde
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Ned Tijdschr Geneeskd · Dec 2002
Review[Sequential analysis in clinical and epidemiological research].
In clinical trials and epidemiological studies, interim analyses are usually performed for ethical or economical reasons, although efficiency aspects can also be a reason. The analysis is referred to as group-sequential analysis or continuous-sequential analysis, dependent on the number of interim analyses performed. Repeated testing of cumulative data requires an adjustment to the significance level or type I error alpha of a statistical test. On average a (group-)sequential analysis of a clinical or epidemiological study requires less patients than the analysis of a fixed-sample study.
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Ned Tijdschr Geneeskd · Dec 2002
Case Reports[Methemoglobinemia due to ingestion of isobutyl nitrite ('poppers')].
Two male students, aged 20 and 21 years, developed central cyanosis shortly after drinking 5 ml of 'poppers' (isobutyl nitrite). They presented with methaemoglobinaemia and were hospitalised. After treatment with oxygen and intravenous fluids they could be discharged in good health the following day. ⋯ Overdose can result in methaemoglobinaemia: the presence of oxidized haemoglobin which is unable to transport oxygen. Depending on the serum level of methaemoglobin this may result in central cyanosis, unconsciousness, coma and even death. Patients with high methaemoglobin levels should be treated with i.v. methylene blue.