Incident data indicators

The fact that the model connecting error types with their causes may change as a result of gaining further experience with the data collection system means that the informahon gathered on the PIFs in a situation may also change. For example, if incident data indicates the neglect of safety procedures because of production pressures, then the questions relating to this area wUl need to be extended. 

Flame dynamics is intimately related to combustion instability and noise radiation. In this chapter, relationships between these different processes are described by making use of systematic experiments in which laminar flames respond to incident perturbations. The response to incoming disturbances is examined and expressions of the radiated pressure are compared with the measurements of heat release rate in the flame. The data indicate that flame dynamics determines the radiation of sound from flames. Links between combustion noise and combustion instabilities are drawn on this basis. These two aspects, usually treated separately, appear as manifestations of the same dynamical process. 

CHD is the leading cause of death among women in the United States. Retrospective data indicated that HRT was associated with a decrease in risk of CHD by 30% to 50%.21 However, the results of recent RCTs demonstrate that HRT does not prevent or treat CHD in women and that it actually may cause an increase in CHD events. The HERS, published in 1998, was the first RCT conducted in women with established CHD. This trial demonstrated an increased incidence of CHD events within the first year of treatment with HRT and an increased risk of venous thromboembolism (VTE) and gallbladder disease. There was a trend of decreasing incidence... 

Breast cancer is the most common cancer in women in the United States. Observational data indicated an association between HRT and breast cancer risk. The WHI was the first RCT to demonstrate an increased risk of invasive breast cancer among women taking HRT. In fact, the trial was stopped early owing to an increased incidence of breast cancer in women taking HRT (0.38%) compared with placebo (0.3%) (HR 1.26, 95% Cl 1-1.59). This translates into an NNTH of 1250 and 8 more cases of invasive breast cancer for every... 

S. pneumoniae, N. meningitidis, and H. influenzae type b dramatically. Prior to the availability of Hib conjugate vaccines, Hib meningitis or other invasive disease was documented in 1 in 200 children by the age of 5 years.5 Widespread use of the Hib vaccine has reduced the incidence of invasive Hib disease by 99% and has shifted the age distribution of bacterial meningitis to older age groups (from 15 months in 1986 to 25 years in 1995).1,6 Recent data indicate that routine use of the 7-valent... 

Acrylonitrile alone has little tendency to produce duodenal ulcers in animals, but pretreatment with phenobarbital or Aroclor results in a marked increase in the incidence of such ulcers (Szabo et al. 1983, 1984). Although the mechanism of the ulcerogenic effect is not obvious, these data indicate that agents which enhanced mixed-function oxidase activity may also increase the toxicity of acrylonitrile. 

The package insert provides preliminary data indicating a higher incidence of thromboembolic events with the patch. The benefits of increased compliance must be weighed against the risk of increased estrogen exposure and possibly more thromboembolic events. 

In spite of its current popularity in the pharmaceutical industry, the use of two control groups is opposed by some statisticians on the grounds that a significant difference between the two groups may indicate that the study was compromised by excessive, uncontrolled variation. Haseman et al. (1986), however, analyzed tumor incidence data from 18 color additives tested in rats and mice and found that the frequency of significant pairwise differences between the two concurrent control groups did not exceed that which would be expected by chance alone. 

In the first set of experiments, the water vessels had rusted bottoms. Of the 21 tests, 14 produced explosions, but no correlation of explosion probability could be deduced. It was reported that, in all tests, molten aluminum reached the bottom of the vessel. High-speed movies showed that the entire explosion sequence between the first visible disturbance in the system to a full-scale chemical reaction was very rapid (on the order of 600 /Ltsec). Note that the word chemical was used in the quote. Lemmon suggests that chemical reactions play a key role in the explosion phenomenon, particularly for violent incidents. The proof that chemical reactions are important stems from the finding that strong explosions produced light and, also, limited spectrographic data indicated local temperatures in excess of 3000 K. The emphasis on chemical reactions was not stressed in the work of other investigators. 

The data in Table 12.5 are the result of a pooling of results from a number of different products that were spot-checked for a number of different residues (drugs, antibiotics, sulfonamides, pesticides, antimicrobials). As can be seen from these limited data, the number of samples is quite small in total but can be reflective of the residue status of various products. Overall, the data indicate a very low incidence of both antibiotic and sulfonamide residues in the imported products. 

The Secret to Measuring Process Safety Performance Combine Process Incident Data with Leading Indicators, Steve Arendt... 

A third type of dose response relationship has been proposed, which is increasingly gaining acceptance, and this is the hormetic kind. This kind of dose response, for which there is experimental evidence, involves opposite effects at low doses, giving rise to a U-shaped or J-shaped curve (Fig. 2.11). That is, there may be positive or stimulatory beneficial effects at low doses. For example, some data indicate that at low doses of dioxin, the incidence of certain cancers in animals exposed is less than occurs in controls. Another example is alcohol (ethanol), for which there is evidence from a number of studies that low to moderate intake in man leads to lower levels of cardiovascular disease. Of course, high levels of intake of alcohol are well established to cause liver cirrhosis, various cancers, and also damage to the cardiovascular system. 

Several studies (e.g., Newhouse and Berry 1976 Nicholson et al. 1982 Peto et al. 1982) indicate that the risk of mesothelioma from a given level of exposure to asbestos depends primarily upon the time elapsed since exposure (latency), with risk increasing exponentially with time after a lag period of about 10 years. Based on this, EPA (1986a) fit exposure-incidence data from four studies (Finkelstein 1983 Peto 1980 Peto et al. 1982 Seidman 1984) to the following equation ... 

Oxidation of the styrene moiety and changes in the nitrogen environment in benzotriazole took place in 94. Available data confirm that the surface photooxidation of polymers containing aromatic moieties can differ from that of the bulk material [86]. This is due to the higher partial pressure of oxygen and incident photon flux in the surface area. Transmission IR data indicate that the quenching capabilities of benzotriazole moieties in the copolymer 94 are not active in inhibiting surface oxidation. 

During the past 30 years numerous studies have assessed the potential role of vitamin C in the treatment or prevention of the common cold. During this time, articles have been published which both support [61-64], and refute [65-68] any positive benefit for vitamin C in the common cold. These differences arise mainly from the fact that investigators have employed different study protocols, which makes inter-study comparisons difficult. Moreover, the use of vitamin C had become an emotive issue and this has led to the publication of a number of articles with considerable bias (both for and against) its use as a treatment for the common cold. However, careful retrospective analysis of these data indicates that supplementation with gram amounts of vitamin C may indeed decrease the severity of cold symptoms, although the incidence of infection appears to be changed little. 

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