Retrospective control

Is Effexor more effective for depression than an SSRI Med Lett Drugs Ther 2004 46 15-16. Kirby D, Harrigan S, Ames D. Hyponatraemia in elderly psych iatric patients treated with selective serotonin reuptake inhibitors and venlafaxine a retrospective controlled study in an inpatient unit. Int 1 Geriatr Psychiatry 2002,17 231-237. 

In the international context there are already specimen banks serving biological, ecological, medical and other kinds of projects (15-20). The objectives of the BCAA put an emphasis on environmental chemistry and the establishment of baselines similar to the approaches followed by other ESBs, i.e., long-term storage of representative environmental specimens for future analyses, retrospective control and new research using parameters which are not being studied at present. Chemical characterization of specimens is also a major objective. 

Sheridan R, Montgemery AA, Fahey T. NSAID use and BP in treated hypertensives a retrospective controlled observational study. JHum Hypertens (2005) 19,445-50. 

There is little evidence relating to the pharmacoeconomic aspects of the use of quetiapine. In the UK, a retrospective audit of 20 patients (Lee et al, 1998), published only as a conference abstract, tentatively suggested decreased costs for those patients, largely through a reduction in hospital stay and resource use. Quetiapine may also improve quality of life (Hellewell et al, 1999). A large, randomized, controlled pharmacoeconomic evaluation is apparently under way (Drummond et al, 1998) and results are awaited. 

To be useful to those concerned with choices in the allocation of health and social care resources, the data for economic evaluations need to be timely, relevant, credible and accurate (Davies, 1998). As a minimum, the costs associated with the interventions should be estimated from activity data, which quantify resources used, and price or unit cost data. Often evidence from well-controlled prospective trials with high internal validity is required to establish whether differences in economic end points are directly attributable to the interventions. However, the economic evaluations of acetylcholinesterase inhibitors estimated costs from retrospective analysis of available datasets Qonsson et al, 1999b), analysis of published literature (e.g. Stewart et al, 1998) and expert opinion (e.g. O Brien et al, 1999 Neumann et al, 1999). This means that it is not clear whether differences in costs were due to the anticholinesterase inhibitors or to other factors such as availability of services in different areas, the living situation of the patient, or disease severity. 

A retrospective case-control study conducted in humans compared spontaneous abortion rates among women who had been exposed occupationally or nonoccupationally to trichloroethylene and other solvents to rates among women without solvent exposure (Windham et al. 1991). The authors observed approximately three times the risk of spontaneous abortion with exposure to trichloroethylene. This risk increased further when women with less than a half hour of exposure to trichloroethylene each week were excluded from the analysis. However, a consistent dose-response relationship was not observed, and most of the women were exposed to a variety of solvents, not just trichloroethylene. 

Reproductive Toxicity. Increased miscarriages were reported in one study of nurse-anesthetists exposed to trichloroethylene and other solvents (Corbett et al. 1974). A retrospective case-control study has should an approximate 3-fold increase in spontaneous abortion in women exposed to trichloroethylene and other solvents (Windham et al. 1991). Significant effects on sperm parameters were not observed in men occupationally exposed to trichloroethylene (Rasmussen et al. 1988). Adverse reproductive effects were not noted in humans that ingested water contaminated with trichloroethylene and other solvents (Byers et al. 

It must be remarked that terminology is not consistent and there are many widely used synon)ms. Quality control in this Chapter refers to practices best described as internal quality control. Quahty assessment is often referred to as external quality control, proficiency testing, interlaboratory comparisons, round robins or other terms. Internal Quality Control and External Quality Assessment are preferred because they best describe the objectives for which the RMs are being used, i.e. the immediate and active control of the results being reported from an analytical run or event, and an objective, retrospective assessment of the quality of those results. 

Develop policy-supporting SOPs on computer systems. These may include development, testing, maintenance and support, quality assurance, change control, source code management, system retirement, retrospective evaluation, evaluation of vendor-supplied systems, etc. 

In this section, we consider several syntheses of six illustrative compounds. We examine the retrosynthetic plans and discuss crucial bond-forming steps and the means of stereochemical control. In this discussion, we have the benefit of hindsight in being able to look at successfully completed syntheses. This retrospective analysis can serve to illustrate the issues that arise in planning a synthesis and provide examples of solutions that have been developed. The individual syntheses also provide many examples of the synthetic transformations presented in the previous chapters and of the use of protective groups in the synthesis of complex molecules. The syntheses shown... 

All data must, of course, be searchable, retrievable, and subject to acceptance or rejection based on both automated and retrospective QC analysis. Reports must be flexible in content yet easily assembled, intuitively understandable, and easily shared with appropriate security and yes, it would be nice if the reports themselves could become, like the assay protocols, version controlled, searchable documents residing in an appropriately indexed relational database. These are just the basic requirements. 

One response may be that it is possible to manage the red tide at the source of the bloom (8) or that there is no need to manage a red tide over vast areas, merely in localized ones that are of special interest. The point is moot until a suitable control agent is available. A considerable number of chemicals have been reviewed for possible red tide control substances, (9), and in retrospect this type of research is subject to ultimate failure because the first criterion of a successful control agent (chemical or biological) has not been considered. 

No information on the carcinogenic potential of polyalphaolefin hydraulic fluids was located. Studies designed to assess carcinogenicity in animals exposed via inhalation, oral, and dermal routes or a well-controlled cohort retrospective or prospective study would be useful for determining the carcinogenic potential of polyalphaolefin hydraulic fluids. 

Major drawback Dose, indication, timing may not be standardized and therefore could confound associations if prospective, then same drawback as clinical trial if retrospective, same drawback as case-control Prospective study requiring follow-up time until endpoints develop to measure response... 

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