background: medical error is defined as an adverse event caused by medical management, which can be prevented. the aim of this study was to investigate the accuracy of diagnosis of oral and maxillofacial diseases made by health care practitioners. methods: a descriptive cross sectional study was done between apr. 2009 and mar.2010. 372 patients with oral and maxillofacial lesions who had referr...

BACKGROUND Effective community-partnered and patient-centered outcomes research needs to address community priorities. However, optimal sampling methods to engage stakeholders from hard-to-reach, vulnerable communities to generate research priorities have not been identified. METHODS In two similar rural, largely Hispanic communities, a community advisory board guided recruitment of stakehold...

In this paper, we are concerned with random sampling of an n dimensional integral point on an (n−1) dimensional simplex according to a multivariate discrete distribution. We employ sampling via Markov chain and propose two “hit-and-run” chains, one is for approximate sampling and the other is for perfect sampling. We introduce an idea of alternating inequalities and show that a logarithmic sepa...

Referral of retronasal odors to the mouth is a fundamental phenomenon of flavor perception. A previous study from this laboratory provided evidence that, contrary to prior speculation, taste rather than touch was the primary factor in retronasal odor referral. The present study further investigated this question by studying the role of congruency between taste and odor on retronasal odor referr...

BACKGROUND Malaria case management is a key strategy for malaria control. Effective coverage of parasite-based malaria diagnosis (PMD) remains limited in malaria endemic countries. This study assessed the health system's capacity to absorb PMD at primary health care facilities in Uganda. METHODS In a cross sectional survey, using multi-stage cluster sampling, lower level health facilities (LL...

Importance sampling, particularly sequential and adaptive importance sampling, have emerged as competitive simulation techniques to Markov–chain Monte–Carlo techniques. We compare importance sampling and the Metropolis algorithm as two ways of changing the output of a Markov chain to get a different stationary distribution.

We analyze the convergence to stationarity of a simple nonreversible Markov chain that serves as a model for several nonreversible Markov chain sampling methods that are used in practice. Our theoretical and numerical results show that nonreversibility can indeed lead to improvements over the diffusive behavior of simple Markov chain sampling schemes. The analysis uses both probabilistic techni...

The difficulty in accessing hard-to-reach populations as men who have sex with men presents a dilemma for HIV surveillance as their omission from surveillance systems leaves significant gaps in our understanding of HIV/AIDS epidemics. Several methods for recruiting difficult-to-access populations and collecting data on trends of HIV prevalence and behavioural factors for surveillance and resear...