Surveys validity

The survey consisted of 74 yes/no questions written by the Minnesota team. These had been culled from a larger group of questions through validation studies by Bailey s group during the development of the survey. Valid questions were retained, invalid questions were dropped. As far as we could determine, however, no question-by-question validation studies had been carried out since the initial development of the survey in about 1980. 

The methodology and the pigging tool has been tested and validated during a demonstration survey conducted on the Danish 107 kilometre 20 oil pipeline running from the West Coast of... 

The survey in the present section shows quite clearly that it is not possible to assign a fixed value of a to a given adsorptive, which will remain valid for its adsorption on ail adsorbents. As demonstrated in Section 2.7, nitrogen and argon would seem to provide the best approximation to a constant effective molecular area, with = 16-2 A and a, (Ar) = 16-6 A. ... 

The marketing information primarily identifies either problems or opportunities. Problems will relate to your existing products and services and should indicate why there has been a decline in sales or an increase in returns. In order to solve these problems a search for possible causes should be conducted and one valid method for doing this is to use the Cause and Effect Diagram. Opportunities will relate to future products and services and should indicate unsatisfied wants. There are three ways of collecting such data by observation, survey, and experiment. 

What is needed is an alternative approach which permits development of valid cause and effect relationships. This strategy, one involving intensive surveys, is referred to here as mechanistic. The Willamette River, Oregon, USA, is used as a case study to illustrate quantitative, semi-quantitative and qualitative approaches to mechanistic assessment of river water quality using, respectively, dissolved oxygen depletion, erosion/deposition and potentially toxic trace elements as examples. 

In this phase of the risk assessment, the validity and reliability of conclusions and advice to risk managers depend on the quality, reliability, and relevance of available exposure data. Therefore it is necessary to (1) critically review the facts from food composition tables and the reasons for differences reported by and within countries, (2) consider the way foods are categorized and thus made comparable (or not) in food consumption surveys, and (3) explore how to refine assessments as more information becomes available. ... 

Ilyukhin, S.V., Haley, T.A., and Singh, R.K., A survey of control system validation practices in the food industry, Food Control, 12, 297, 2001. 

AO AC Technical Division on RMs United States Department of Defense United States Food and Drug Administration US Geological Survey United States Pharmacopoeia Valid Analytical Measurement, UK World Health Organization... 

This section provides a short introductory survey of an area of science which is not only mathematically exacting, but also of fundamental importance for certain aspects of biogenesis. Thermodynamics, a sub-discipline of physics, deals not only with heat and dynamics , but formulated more generally, thermodynamics is concerned with energy and entropy and deals with theorems which are valid across almost all areas of physics. 

It is inappropriate in this survey to attempt to summarise in a short space the results of all the above treatments, but virtually all the calculations indicate that in M(Cp)2 species the 7r(ej) metal-ligand interaction is dominant in the metal to ring bonding. However, debate has largely been concentrated on two points, in the first place the extent of the validity (or otherwise) of Koopmans theorem, and, further, the question of the correct energetic ordering (5 < o < n or o < 5 < n) of the mainly metal tf-type orbitals. 

Methods which can be used to determine the size and shape of polysaccharides have been reviewed.107 (A critical survey of these has recently been given by Sadron108 and by Ogston.109) Special problems exist in the case of the undegraded starch components. In view of the branched nature of amylopectin and the large size of the amylose molecule, chemical methods of estimating size are inadequate, and it is questionable whether results are valid.38 The free components may also aggregate in aqueous solution. Study of derivatives is therefore more convenient, and the preparation of these is an essential preliminary to estimations of molecular size. 

Separating the data transformation into three distinct steps enforces a completely modular software design. In practice, the data transformation is executed via command shell scripts, using freely available software for both the XSLT transformation and XSD validation. The raw data contained in the 39 surveys in the New Brunswick compilation are exported into 7,000 individual KML files, which can be viewed online at http //gdr.nrcan.gc.ca/geochem. 

Although in most applications no assessment is made unless a component fails prematurely, many respondents to the survey mentioned above reported that they examine and analyse polymer components taken out of service at the end of their service lives. In this way they could establish directly whether the components were still fit for use, and could feed this back to validate the process of life prediction at the design stage. Such information is generally retained within a company, but it was gratifying to learn that this practice is more common than was thought. 

Nonetheless, like most other aspects of odour control, there remain unanswered questions. Chief among these is the relationship between odour potential of a sludge, and the actual level of nuisance found during, say, application to land. Elucidating this relationship requires fairly extensive surveys, because of the variability of weather conditions. Paradoxically, such surveys would depend for their validity on the air sampling methods used the very source of inaccuracy that the Odom Potential test was developed to circumvent. 

A validation protocol adapted from the experiences during the method development defines the scope of the validation study (goal of the study, regulating guidelines, key method parameters, etc.). To investigate the adequate method performance, these features (e.g., range of analyte concentration), together with a statement of any fitness-for-purpose criteria, have to be specified in the validation protocol. A basic check has to provide that the reasonable assumptions about the principles of the method are not seriously flawed. In this process, sources of error in analysis have to be listed (Table 4) and their effects have to be checked. The validation should, as far as possible, be conducted to provide a realistic survey of the number... 

Level 1 sampling provides a single set of samples acquired to represent the average composition of each stream. This sample set is separated, either in the field or in the laboratory, into solid, liquid, and gas-phase components. Each fraction is evaluated with survey techniques which define its basic physical, chemical, and biological characteristics. The survey methods selected are compatible with a very broad spectrum of materials and have sufficient sensitivity to ensure a high probability of detecting environmental problems. Analytical techniques and instrumentation have been kept as simple as possible in order to provide an effective level of information at minimum cost. Each individual piece of data developed adds a relevant point to the overall evaluation. Conversely, since the information from a given analysis is limited, all the tests must be performed to provide a valid assessment of the sample. 

So, ICSR are reports of genuine, general clinical concerns about a drug and suspected reaction. All must be treated as valid , in fact they should be labelled clinical concerns rather than spontaneous reports (a term that has long use) because the label is descriptively more explicit. Other reasons for reporting such as medico-legal considerations and current awareness of a particular drug problem were identified, but were of much less frequent concern to the international reporters surveyed. 

---