flow study

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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.

flow study

References in periodicals archive ?
If the access blood flow study was performed toward the end of a hemodialysis treatment, a high-flow access could be masked due to reductions in blood volume, cardiac output, and MAP.
For example, prior to surgical intervention (transurethral resection of the prostate [TURP]) on a patient with known BPH, who also presents with urinary retention and severe diabetic neuropathy, the pressure flow study can be performed to prove obstruction (structural problem) and rule out atonic or hypotonic bladder (functional problem).
The Intravesical prostatic protrusion is correlated with the severity of Bladder outlet obstruction due to BPH as assessed by symptoms score, QOL index, Uroflowmetry, cystoscopy and confirmed with Pressure Flow study.
The rainfall-induced overland flow study in 1998 used a pair of adjacent irrigation bays previously established for the purpose of monitoring nutrient exports on the Macalister Research Farm (38[degrees]0'S, 146[degrees]54'E) in the Macalister Irrigation District of south-eastern Australia.
She was informed of the uneventful overnight shift and of the plan for brain flow study at approximately 1000.
This is further discussed in the section on stick-slip flow study.
The flow study was being conducted in that particular interceptor because a major new development had been planned for the Uptown area that would add two mgd of flow to the line.
The load flow study is an analysis of system capability to supply energy to the connected load under steady state conditions.
Although the 1995 project may be described as a replay of the 1979 international news flow study (Sreberny-Mohammadi, Nordenstreng, Stevenson, and Ugboajah, 1985) in which Stevenson and Sreberny-Mohammadi were key collaborators, the emerging global news agenda, topography, and players remained uncharted after the cold war.
During the development of this project, the Federal Reserve Bank of Dallas initiated a cash flow study to establish the normal range of cash activities for each of the financial institutions that used that Reserve Bank's cash services.
Your comment brings to mind something in the FERF funds flow study ("The Funds Statement: Structure and Use," by Alan Seed, III).
Engineering, Manufacture, Inspection at supplier%s works, supply insurance, Transport, storage, Erection, Testing, Commissioning and provisional take over with associated power evacuation system Including grid connectivity approval from Tamil Nadu State Electricity Authorities, Load Flow Study, bay extensions, external transmission lines and right of way.