Learn More
This article describes some of the important statistical properties of the commonly used permuted-block design, also known simply as blocked-randomization. Under a permutation model for statistical tests, proper analyses should employ tests that incorporate the blocking used in the randomization. These include the block-stratified Mantel-Haenszel chi-square(More)
The statistical properties of simple (complete) randomization, permuted-block (or simply blocked) randomization, and the urn adaptive biased-coin randomization are summarized. These procedures are contrasted to covariate adaptive procedures such as minimization and to response adaptive procedures such as the play-the-winner rule. General recommendations are(More)
Six-month regimens that include rifampin for the treatment of tuberculosis in patients without human immunodeficiency virus (HIV) infection are recommended because of low percentage of relapses. Whether a similar duration of therapy should be used to treat tuberculosis in HIV-infected patients is unclear. Six studies of patients with HIV-infection and 3 of(More)
Infection with human immunodeficiency virus (HIV) has been associated with increased rates of single- and multidrug-resistant (MDR) tuberculosis in the New York City area. In order to examine the relationship of HIV infection to drug-resistant tuberculosis in other selected regions of the United States, we established a registry of cases of culture-proven(More)
A double-blind, placebo-controlled trial was set up to compare clindamycin and pyrimethamine as prophylaxis for toxoplasmic encephalitis (TE) in HIV-infected patients at risk of the disorder. Interim analysis showed that clindamycin-treated patients were 4.4 (95% confidence interval 1.3-15.2) times more likely to experience an adverse effect that(More)
Many medical studies rely on the evaluation of large amounts of clinical data. Neither a trained technician nor a standard computer program can be used to perform the evaluation which requires clinical Judgement. We are currently doing research on the use of expert systems to reduce the tlme and expense of having a medlcal expert perform these subjective(More)
BACKGROUND The erosion of the early mortality advantage of elective endovascular aneurysm repair (EVAR) compared with open repair of abdominal aortic aneurysm remains without a satisfactory explanation. METHODS An individual-patient data meta-analysis of four multicentre randomized trials of EVAR versus open repair was conducted to a prespecified analysis(More)
Powerful new training algorithms developed for ar tificial neural networks hold th e promise of identifying regulari ties in t he t raining data an d generalizing over t he test data. T he backprop a-gatio n algorithm is one such t raining algorithm t ha t, with th e use of hidden units, can learn functions such as exclusive-or. These fun ctions can be(More)