confidence interval

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the space between two objects or parts; the lapse of time between two events.
AA interval the interval between two consecutive atrial stimuli.
atrioventricular interval (AV interval)
2. in dual chamber pacing, the length of time between the sensed or paced atrial event and the next sensed or paced ventricular event, measured in milliseconds; called also atrioventricular or AV delay.
cardioarterial interval the time between the apical beat and arterial pulsation.
confidence interval an estimated statistical interval for a parameter, giving a range of values that may contain the parameter and the degree of confidence that it is in fact there.
coupling interval the distance between two linked events in the cardiac cycle.
His-ventricular (H-V) interval an interval of the electrogram of the bundle of His, measured from the earliest onset of the His potential to the onset of ventricular activation as recorded on eight of the intracardiac bipolar His bundle leads or any of the multiple surface ECG leads; it reflects conduction time through the His-Purkinje system.
lucid interval
1. a brief period of remission of symptoms in a psychosis.
2. a brief return to consciousness after loss of consciousness in head injury.
PA interval the interval from the onset of the P wave on the standard electrocardiogram (or from the atrial deflection on the high right atrial ECG) to the A wave on the His bundle ECG; it represents intra-atrial conduction time.
postsphygmic interval the short period (0.08 second) of ventricular diastole, after the sphygmic period, and lasting until the atrioventricular valves open.
P–R interval in electrocardiography, the time between the onset of the P wave (atrial activity) and the QRS complex (ventricular activity).
presphygmic interval the first phase of ventricular systole, being the period (0.04–0.06 second) immediately after closure of the atrioventricular valves and lasting until the semilunar valves open.
QRST interval (Q–T interval) in the electrocardiogram, the length of time between ventricular depolarization (the Q wave) and repolarization (the T wave); it begins with the onset of the QRS complex and ends with the end of the T wave.
VA interval [ventricular-atrial interval] the interval between a ventricular stimulus and the succeeding atrial stimulus; it is equal to the AA interval minus the atrioventricular interval.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

con·fi·dence in·ter·val (CI),

a range of values for a variable of interest, constructed so that this range has a specified probability of including the true value of the variable.
Farlex Partner Medical Dictionary © Farlex 2012

confidence interval

A measure of the precision of an estimated value, which corresponds to a range of values consistent with the data that have a high probability (± 95%) of encompassing the "true" value. The confidence interval is expressed in the same units as the estimate. Wider confidence intervals indicate lower precision; narrower intervals indicate greater precision.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

confidence interval

Statistics A range of values for a variable of interest–eg, a rate, constructed so that the range has a specified probability of including the true value of the variable. See Confidence limits.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

con·fi·dence in·ter·val

(CI) (konfi-dĕns in'tĕr-văl)
Range of values for a variable of interest, constructed so that this range has a specified probability of including the true value of the variable.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

confidence interval (CI)

A statistical term that quantifies uncertainty. In a clinical trial, the 95% confidence interval (the interval usually employed) for any relevant variable is the range of values within which we can be 95% sure that the true value lies for the entire population of people from which those patients participating in the trial are taken. The greater the number of patients on which the confidence interval is based the narrower it becomes.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
In the above instance, the small sample sizes and the relatively large standard deviation produce confidence intervals for both the mean and the median with great breadth.
In Sections 1 and 2, Smithson establishes the rationale for considering confidence intervals. Section 3 explores issues of central confidence intervals; Section 4 explains noncentral confidence intervals and their computations for standardized effect sizes; Section 5 explores confidence intervals in analyses of variance and regression statistics; Section 6 explores confidence intervals for categorical data analysis; Section 7 explores significance tests and power analysis; and Section 8 provides concluding remarks.
So long as the taxpayer uses the lower limit of the confidence interval described above when claiming deductions or credits based on a sample, the IRS will not challenge the sampling procedures.
But if we increase the sample size to 100 apples and 100 oranges, our confidence intervals decrease, and we can now tell apples do have lower values than oranges (FIGURE 2).
As a surrogate model Gaussian Process modeling is employed to find approximate solution values together with their confidence intervals. As GP-DEMO works on the same principles as DEMO, the quality of its results is expected to be similar to the results of DEMO, but with fewer exact solution evaluations.
For example, 95% confidence level means that if many samples of the same size are collected and the confidences intervals are computed then, in the long run, about 95% of these confidence intervals would contain the true mean.
Consequently, it is important to supplement a squared multiple correlation point estimate with a confidence interval for the population squared multiple correlation.
Study-specific relative risks with 95% confidence intervals were pooled using a random effects model.
Compute fuzzy confidence intervals of [[??].sub.R] = [[([[??].sub.R]).sup.L.sub.[alpha]], [([[??].sub.R]).sup.U.sub.[alpha]]] for [alpha] [member of] [0, 1], the lower fuzzy confidence interval [L([[??].sup.L.sub.[alpha]]), U([[??].sup.L.sub.[alpha]])], and the upper fuzzy confidence interval [L([[??].sup.U.sub.[alpha]]), U([[??].sup.L.sub.[alpha]])].
Therefore, it is becoming advisable to provide, in addition to the statistical test and the p-value, other statistical measures, such as the effect size, confidence intervals around the statistical test, and even statistical confidence intervals for effect size (APA, 2010; Bailar and Mosteller, 1988; Belia, Fidler, Williams and Cumming, 2005; Cohen, 1994; Cumming, 2008, 2009; Cumming and Fidler, 2009; Cumming and Finch, 2001, 2005; Wilkinson and the Task Force on Statistical Inference, 1999; Wolfe and Hanley, 2002) or robust estimations of the confidence intervals of the robust effect size (Algina, Keselman and Penfield, 2005; Keselman, Algina, Lix, Wilcox and Deering, 2008).
We used Cox proportional hazards models to estimate hazard ratios and 95% confidence intervals for the association of baseline and follow-up measurements of serum glucose and insulin with breast cancer risk.