“An expert is one who knows more and more about less and less until he knows absolutely everything about nothing.”

MedCalc is a complete statistical program



MedCalc is the most user-friendly software forReceiver Operating Characteristic curve (ROC curves) analysis. The MedCalc ROC module includes comparison of up to 6 ROC curves.The software includes Bland & Altman plot,Passing and Bablok and Deming regression and many other procedures for method comparison studies and laboratory method evaluation.

Create ROC curves easily

MedCalc allows to perform ROC curve analysis easily and accurately. Our ROC curve analysis module includes:
  • Area under the curve (AUC) with standard error (SE) and 95% confidence interval (CI). The standard error can be calculated using 2 methods:
    • DeLong et al. (1988)
    • Hanley & McNeil (1982)
    The Confidence Interval for the AUC can be calculated using the following methods:
    • Binomial exact confidence interval
    • AUC ± 1.96 its Standard Error.
  • Calculate optimal criterion value taking into account costs: option to calculate the optimal criterion value taking into account the disease prevalence and cost of false and true positive and negative decisions (Zweig & Campbell, 1993).
  • Calculation of Youden index.
  • ROC curve graph with 95% Confidence Bounds.
  • Plot of sensitivity and specificity versus criterion values.
  • Interval likelihood ratios.
  • Sample size calculation for area under ROC curve and comparison of ROC curves.
MedCalc creates a list of sensitivity, specificity, likelihood ratios, and positive and negative predictive values for all possible threshold values.
Threshold values can be selected in an interactive dot diagram with automatic calculation of corresponding sensitivity and specificity.

Advanced options

MedCalc offers the following unique advanced options:
  • Estimation of sensitivity and specificity at fixed specificity and sensitivity: an option to compile a table with estimation of sensitivity and specificity (with a BCa bootstrapped 95% confidence interval) for a fixed and prespecified specificity and sensitivity of 80%, 90%, 95% and 97.5% (Zhou et al., 2002).
  • Bootstrap Youden index confidence interval: an option to calculate a BCa bootstrapped 95% confidence interval (Efron & Tibshirani, 1994) for the Youden index and its associated criterion value.
These options require bootstrapping which is a computationally intensive and sometimes time consuming technique.

Comparison of ROC curves

  • MedCalc can compare up to 6 ROC curves with the method of DeLong et al. (1988) or Hanley & McNeil (1983). The software gives the difference between the areas under the ROC curves, with standard error, 95% confidence interval and P-value.

Graphs





Method comparison, method evaluation and agreement

Method comparison & evaluation

MedCalc contains the following statistical procedures specifically for Method comparison & evaluation:

Agreement & responsiveness

For analyzing agreement and responsiveness, MedCalc offers:

ROC curve analysis

MedCalc is the most commonly used software for ROC curve analysis in biomedical literature. See:ROC curve analysis features of MedCalc and MedCalc manual: ROC curve analysis.

Reference interval

MedCalc calculates reference intervals using the Normal distribution, a non-parametrical percentile method, and optionally a robust method as described in the CLSI Guidelines C28-A3.See MedCalc manual: Reference interval

Control chart

The control chart is a graph used to study how processes or measurements change over time with data plotted in time order. Rules are applied (Westgard et al., 1981) to automatically SIGNALwhen the process is out of control.See MedCalc manual: Control chart

Youden plot

The Youden plot is a graphical method to analyse inter-laboratory data, where all laboratories have analysed 2 samples. The plot visualises within-laboratory variability as well as between-laboratory variability.MedCalc draws the original Youden plot and common variations, including an adaptation for non-comparable samples.See MedCalc manual: Youden plot

MedCalc compatibility

MedCalc is compatible with all 32-bit and 64-bit Windows versions starting with WINDOWS XP(with Service Pack 3).
It has obtained the official “Compatible with” Windows Vista, WINDOWS 7 and Windows 8 logo from Microsoft.
Software with the Compatible with Windows logo is certified to be virus free, to install and uninstall cleanly, and to integrate seamlessly in Windows.
                                                
  
       
For technical details about Windows certification, see Certification requirements for Windows desktop apps (Microsoft site).

System requirements

  • PC with WINDOWS XP, Windows Server 2003, Windows Vista, Windows 7 or Windows 8 (32-bit and 64-bit versions).
  • 512 Mb of memory.
  • 20 Mb free space on the hard disk.

Software Accessibility

MedCalc Software is committed to providing high-quality products and services that are both useful and accessible to all potential users, including individuals with disabilities.
Amongst others, MedCalc provides:
  • an option for large dialogs: make text and buttons indialogs larger and easier to read.To enable large dialogs in MedCalc, you start MedCalc and select Options in the Tools menu. In the left panel, click General and next select the option Large dialogs in the right panel.
  • support for high resolution displays (high DPI support): make text and icons larger without adjusting your monitor resolution by changing the DPI (dots per inch) scale.To enable Windows high DPI you click Control Panel, and type display into search box. Then click Display, and select a preset size or enter a customize size. The change takes place the next time you log into Windows.
  • support for high contrast display settings. High Contrast is a feature that heightens the color contrast of some text and images on your computer screen, making those items more distinct and easier to identify.To enable high contrast in Windows:
    • Open Appearance Settings by clicking the Start button and then clicking Control Panel. In the search box, type window color, and then click Change window colors and metrics.
    • Under Basic and High Contrast Themes, click the high-contrast color scheme that you want to use.

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Hi,I,m Basim from Canada I,m physician and I,m interested in clinical research feild and web development.you are more welcome in our professional website.all contact forwarded to basimibrahim772@yahoo.com.


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