Opis: Churchill Livingstone, str 378, stan db+ (podniszczona lekko okładka, zakurzona, nieaktualne pieczątki) ISBN (36) Preface In many scientific disciplines, a pattern can be seen that represents the evolution of the discipline into a mature science. This pattern consists of four principal parts: observation, measurement, mathematical modeling, and prediction. It is obvious that any study of nature begins with observation, but the precision, reliability, and reproducibility of such observations improve dramatically when they can be quantified. Such quantification is, of course, essential for the application of mathematical methods that provide the means for specifying precisely the relationship between variables and giving information not available by direct observation. Such important information is obtained through the development of mathematical models, which are able to describe accurately the phenomenon being studied. The availability of such models makes possible the ultimate objective of all scientific inquiry, namely, the ability to predict the future. In the field of obstetrical ultrasonography, we have seen this pattern emerge over the last 20 years. As a result, powerful new methods have been developed for determining fetal age, estimating fetal weight, evaluating fetal growth, and characterizing fetal dynamics. These methods, based primarily on statistics, provide the obstetrician with an ever-growing ability to monitor fetal development, detect abnormalities, and make better management decisions. Those of us interested in this aspect of obstetrical ultrasonography, however, realize that the strong mathematical orientation of these new methods poses a significant problem for many clinicians. In addition, numerous studies on specific subjects have been done differently and are presented in ways that do not encourage comparisons. In such circumstances, it is difficult to (1) have adequate access to the available information, (2) understand how the data were collected and analyzed, (3) determine if a given subject has been studied appropriately, (4) identify reliable information for use in specific clinical situations, and (5) follow new developments. This book was written to help the reader with these problems. In this book the reader will find the information needed to become well versed in the use of quantitative methods in obstetrical ultrasonography. For those in need of a more extensive statistical background, we have provided a discussion of the principal statistical methods used in this field in a form that emphasizes concept over algebra (Chapters 9-18). The basic principles involved in the measurement process and in validating a quantitative study are discussed in Chapters 1 and 2. In the major applications of quantitative methods in obstetrical ultrasonography, the available literature has been extensively evaluated (Appendices 1-5) and various topics have been summarized (Chapters 3-8). Mathematical models for dating, growth curve generation, and weight estimation are provided together with tables of normal values. In many instances (particularly growth studies), the results of many investigations are presented in tabular form for easy comparison of the data. The chapter on the detection of abnormal growth (Chapter 7) presents the results of different investigations in a standard statistical form so that the collective experience in this area can be seen for the first time. For each of the topics discussed, the respective author has tried to present an overview of the current status of the area and what new directions might be profitably explored. We feel that with the information provided, the reader will be prepared to recognize or conduct a valid quantitative study, select the proper methods and normative data for clinical use, and incorporate new developments as they appear. Achieving these objectives is essential if the benefits of the quantitative approach are to be made available to our patients.
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