In step with the need to develop statistical procedures to manage small-size environmental samples, in this work we have used concentration values of benzene (C6H6), concurrently detected by seven outdoor and indoor monitoring stations over 12 000 minutes, in order to assess the representativeness of collected data and the impact of the pollutant on indoor environment. Clearly, the former issue...

OBJECTIVES In an attempt to elucidate if inducible nitric oxide expression (iNOS) is correlated with the level of inflammation in periapical cysts with accuracy, the goal of this study was to evaluate the expression of iNOS in these ones. METHODS 30 cases were included in this study being iNOS evaluated by means of immunohistochemistry. Statistical analysis was performed by Kruskal-Wallis non...

OBJECTIVES To test effectivity of a two-minute training consisting of a few key-points in ventilation using the self-inflating bag (SIB). STUDY DESIGN Experienced and inexperienced caregivers were asked to mask ventilate a leak free manikin using the SIB before and after the training. Mask leak and pressures were measured using respiratory function monitoring. Pressures above 35 cm H2O were c...

OBJECTIVE To examine spatial-temporal distribution and risk of suicide, as well as trends in suicide mortality rates, in the indigenous and non-indigenous population of the state of Mato Grosso do Sul, Brazil. METHODS Data were obtained from the Information Department of the Brazilian Unified Health System. Deaths recorded as voluntary self-inflicted injuries (ICD-10 codes X60.0 to X84.9) wer...

We consider the problem of testing for seasonal unit roots in monthly panel data. To this aim, we generalize the quarterly CHEGY test to the monthly case. This parametric test is contrasted with a new nonparametric test, which is the panel counterpart to the univariate RURS test that relies on counting extrema in time series. All methods are applied to an empirical data set on tourism in Austri...

Survival analysis is widely applied in many fields such as biology, medicine, and public health. A typical analysis of survival data involves the modeling of time-to-event data, such as the time until death. To find Survival probabilities of the given observations censored or not, use Kaplan-Meier methods of estimation. But this method gives survival probabilities at any specific time. So this ...

BACKGROUND Ensuring that all medical students achieve adequate clinical skills remains a challenge, yet the correct performance of clinical skills is critical for all fields of medicine. This study analyzes the influence of receiving feedback by teaching associates in the context of achieving and maintaining a level of expertise in complex head and skull examination. METHODS All third year st...

As the main part in terrestrial ecosystems, vegetation is the result of long-term effect by variety natural factors of a region. In the same climatic regions, the heterogeneity of natural conditions is small and the vegetation also has certain homogeneity. These provide us a appropriate selection to analyze the vegetation change according to unique phonological characteristics of different regi...

Results Overall, 26 individuals had prediabetes, 28 did not have prediabetes (22 had 1h-OGTT>fasting glycemia, 6 had 1h-OGTT≤fasting glycemia) and 5 had diabetes. The 1h-OGTT≤fasting glycemia and diabetes groups were excluded, and then a non-parametric test (Mann-Whitney U test) was used to analyze data. There were no statistical differences between 1h-OGTT>fasting glycemia and prediabetes grou...

Recurrent event time data are common in biomedical follow-up studies, in which a study subject may experience repeated occurrences of an event of interest. In this paper, we evaluate two popular nonparametric tests for recurrent event time data in terms of their relative efficiency. One is the log-rank test for classical survival data and the other a more recently developed nonparametric test b...