cross-sectional study

study

[stud´e] a careful examination of a phenomenon; see also design.cohort study prospective study.cross-sectional study one employing a single point of data collection for each participant or system being studied. It is used for examining phenomena expected to remain static through the period of interest. It contrasts with a longitudinal s.electrophysiological s's (EPS) studies from within the heart of its electrical activation and response to electrical stimuli and certain drugs. In general they include intravenous and/or intra-arterial placement of one or more electrode catheters at sites in the atria, ventricles, or coronary sinus, and sometimes the pulmonary artery or aorta. They record activity or stimulate the heart at various rates and cadences and are aids in the evaluation of electrophysiologic properties such as automaticity, conduction, and refractoriness. They also initiate and terminate tachycardias, map the sequence of activation, and aid in evaluation of patients for various forms of therapy and for the response to therapy. During these studies catheter ablation procedures, such as radio frequency ablation and electrical ablation, may be performed.flow study uroflowmetry.longitudinal study one in which participants, processes, or systems are studied over time, with data being collected at multiple intervals. The two main types are prospective studies and retrospective studies. It contrasts with a cross-sectional s.pilot study a smaller version of a proposed research study, conducted to refine the methodology of the later one. It should be as similar to the proposed study as possible, using similar subjects, the same setting, and the same techniques of data collection and analysis.prospective study an epidemiologic study in which the groups of individuals (cohorts) are selected on the bases of factors that are to be examined for possible effects on some outcome. For example, the effect of exposure to a specific risk factor on the eventual development of a particular disease can be studied. The cohorts are then followed over a period of time to determine the incidence rates of the outcomes being studied as they relate to the original factors in question. Called also cohort study.

The term prospective usually implies a cohort selected in the present and followed into the future, but this method can also be applied to existing longitudinal historical data, such as insurance or medical records. A cohort is identified and classified as to exposure to the risk factor at some date in the past and followed up to the present to determine incidence rates. This is called a historical prospective study, prospective study of past data, or retrospective cohort study.retrospective study an epidemiologic study in which participating individuals are classified as either having some outcome (cases) or lacking it (controls); the outcome may be a specific disease, and the persons' histories are examined for specific factors that might be associated with that outcome. Cases and controls are often matched with respect to certain demographic or other variables but need not be. As compared to prospective studies, retrospective studies suffer from drawbacks: certain important statistics cannot be measured, and large biases may be introduced both in the selection of controls and in the recall of past exposure to risk factors. The advantage of the retrospective study is its small scale, usually short time for completion, and its applicability to rare diseases, which would require study of very large cohorts in prospective studies. See also prospective s.urinary flow study uroflowmetry.voiding pressure study simultaneous measurement of bladder contraction, urinary flow, and sphincter electromyogram.

cross-sec·tion·al stud·y

1. a study in which groups of individuals of different types are composed into one large sample and studied at only a single timepoint (for example, a survey in which all members of a given population, regardless of age, religion, gender, or geographic location, are sampled for a given characteristic or finding in one day). 2. analysis of (an) anatomic or other structure(s) by means of a series of planar sections or radiographic images through the structure(s) and the surrounding environment. Synonym(s): synchronic study

cross-sec·tion·al stud·y

(kraws'sek'shŭn-ăl stŭd'ē) A study in which groups of individuals of different types are composed into one large sample and studied at only a single point in time (e.g., a survey in which all voters, regardless of age, religion, gender, or geographic location, are sampled in 1 day).
Synonym(s): synchronic study.

cross-sec·tion·al stud·y

(kraws'sek-shŭn-ăl stŭd'ē) 1. Study in which groups of individuals of different types are composed into one large sample and studied at only a single timepoint. 2. Analysis of anatomic or other structure(s) by series of planar sections or radiographic images through the structure(s) and surrounding environment.

单词	cross-sectional study
释义	DictionarySeestudy cross-sectional study cross-sectional study [¦krȯs ¦sek·shən·əl ′stəd·ē] (psychology) The study of groups of individuals differing on the basis of specified criteria (for example, age) at the same point in time. cross-sectional study a method of examining a varied population at one point in time in order to gather data about people at different life stages, or in different circumstances. This method contrasts with LONGITUDINAL STUDIES which investigate groups over a time period, in order to observe the developmental process, the influence of changing circumstances. The advantage of cross-sectional study is that it is quicker, not dependent on changing resources or research teams, and reduces extraneous variables resulting from the passage of time. The disadvantage is that no account of change can be given. cross-sectional study study [stud´e] a careful examination of a phenomenon; see also design.cohort study prospective study.cross-sectional study one employing a single point of data collection for each participant or system being studied. It is used for examining phenomena expected to remain static through the period of interest. It contrasts with a longitudinal s.electrophysiological s's (EPS) studies from within the heart of its electrical activation and response to electrical stimuli and certain drugs. In general they include intravenous and/or intra-arterial placement of one or more electrode catheters at sites in the atria, ventricles, or coronary sinus, and sometimes the pulmonary artery or aorta. They record activity or stimulate the heart at various rates and cadences and are aids in the evaluation of electrophysiologic properties such as automaticity, conduction, and refractoriness. They also initiate and terminate tachycardias, map the sequence of activation, and aid in evaluation of patients for various forms of therapy and for the response to therapy. During these studies catheter ablation procedures, such as radio frequency ablation and electrical ablation, may be performed.flow study uroflowmetry.longitudinal study one in which participants, processes, or systems are studied over time, with data being collected at multiple intervals. The two main types are prospective studies and retrospective studies. It contrasts with a cross-sectional s.pilot study a smaller version of a proposed research study, conducted to refine the methodology of the later one. It should be as similar to the proposed study as possible, using similar subjects, the same setting, and the same techniques of data collection and analysis.prospective study an epidemiologic study in which the groups of individuals (cohorts) are selected on the bases of factors that are to be examined for possible effects on some outcome. For example, the effect of exposure to a specific risk factor on the eventual development of a particular disease can be studied. The cohorts are then followed over a period of time to determine the incidence rates of the outcomes being studied as they relate to the original factors in question. Called also cohort study. The term prospective usually implies a cohort selected in the present and followed into the future, but this method can also be applied to existing longitudinal historical data, such as insurance or medical records. A cohort is identified and classified as to exposure to the risk factor at some date in the past and followed up to the present to determine incidence rates. This is called a historical prospective study, prospective study of past data, or retrospective cohort study.retrospective study an epidemiologic study in which participating individuals are classified as either having some outcome (cases) or lacking it (controls); the outcome may be a specific disease, and the persons' histories are examined for specific factors that might be associated with that outcome. Cases and controls are often matched with respect to certain demographic or other variables but need not be. As compared to prospective studies, retrospective studies suffer from drawbacks: certain important statistics cannot be measured, and large biases may be introduced both in the selection of controls and in the recall of past exposure to risk factors. The advantage of the retrospective study is its small scale, usually short time for completion, and its applicability to rare diseases, which would require study of very large cohorts in prospective studies. See also prospective s.urinary flow study uroflowmetry.voiding pressure study simultaneous measurement of bladder contraction, urinary flow, and sphincter electromyogram. cross-sec·tion·al stud·y 1. a study in which groups of individuals of different types are composed into one large sample and studied at only a single timepoint (for example, a survey in which all members of a given population, regardless of age, religion, gender, or geographic location, are sampled for a given characteristic or finding in one day). 2. analysis of (an) anatomic or other structure(s) by means of a series of planar sections or radiographic images through the structure(s) and the surrounding environment. Synonym(s): synchronic study cross-sec·tion·al stud·y (kraws'sek'shŭn-ăl stŭd'ē) A study in which groups of individuals of different types are composed into one large sample and studied at only a single point in time (e.g., a survey in which all voters, regardless of age, religion, gender, or geographic location, are sampled in 1 day). Synonym(s): synchronic study. cross-sec·tion·al stud·y (kraws'sek-shŭn-ăl stŭd'ē) 1. Study in which groups of individuals of different types are composed into one large sample and studied at only a single timepoint. 2. Analysis of anatomic or other structure(s) by series of planar sections or radiographic images through the structure(s) and surrounding environment. FinancialSeeCross-sectional analysisSee COMSEC Subordinate Switch See CSS
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