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Title Line Plot
Graph Displayed class
Graph Subgroup General Principles
Classification-Graph Type Line Plot
Code Added Yes
Date Original
Original Date 26.08.2011
Modified Date

Contributor/Email fabrice.bancken@novartis.com
Contributor1 Modification/Email

Contributor2 Modification/Email

Contributor3 Modification/Email

Disclaimer The opinions expressed in this document are those of the author and may not represent the opinions of the U.S. Food and Drug Administration or other authors.
Type of Data Categorical and Continuous
Description and Purpose The line plot displays either summary data (e.g., mean and 95 CI limits)or a subject's individual measurements (otherwise known as subject's profile) summary data at a series of time points.

In both cases, the X axis typically represents time, and therefore must be a quantitative axis, in the sense that the distance on the graph between 2 time points should be proportional to the time difference between those timepoints

For summary data,, the Y axis represents the summary results at the time point under consideration which - in most cases - are represented by a symbol and (vertical) error bar.

For subject's profiles, a symbol located at (x,y) represents the result y(laboratory result, vital signs, etc) for the subject under consideration at the time point x. (Example 4)

Connecting lines: The symbols representing points estimates may be connected with lines to outline trends over time.

Special features:

Margin : A margin can be drawn in the plot to hold a particular result. For example, when depicting the change from baseline at each time point during a study [based on available data at the timepoint], one may want to have a margin or side panel in which sensitivity analysis results are shown (LOCF, or other estimate obtained with more sophisticated techniques accounting for missing data). (see Example 1)

A good practice also to display the number of subjects who contributed to the summary data at timepoint Xi (i=1, ...n) (see Example 1). This can be displayed using text or using a bottom small side panel holding another lien plott (see Example 2)
Datasets Other
Data * figure8_data.sas7bdat: Data used for summary line plot example
Example1Title Grouped Line Plot for summary data (with margin / side panel)
Example1Description This example is a grouped (2 groups) line plot. The groups are distinguished by using different colors, line patterns and symbols). Symbols represent the point estimates and lines are joining those together.
This example also illustrates the use of a side panel (right side), which can provide another point of reference, against which one can benchmark the over-time evolution (left panel). In this case, it represents the result at the 'endpoint'.

The number of observations used to compute the point estimate is provided in the bottom part of the plot, both for the over-time part and for the endpoint. One can readily see that the endpoint is not solely using available data at Week 12, but is probably using algorithms to account for missing data (e.g., LOCF imputation).

The example uses two colors with different luminosities, therefore will print with different grayscale levels on a B/W printer.
Example1Image
Click on figure for enlarged image
Example2Title Grouped Line Plot for summary statistics with number observations depicted as a side line plot
Example2Description This example is a grouped (2 groups) line plot. The groups are distinguished by using different colors, line patterns and symbols). Symbols represent the point estimates and lines are joining those together.
This example also illustrates the use of a side panel (bottom side), to represent GRAPHICALLY the number of observations used to compute the point estimate and variability, over time.

The example uses two colors with different luminosities, therefore will print with different grayscale levels on a B/W printer.
Example2Image
Click on figure for enlarged image
Example3Title Grouped Line Plot for Summary Statistics
Example3Description This example is a grouped (2 groups) line plot. The groups are distinguished by using different colors, line patterns and symbols). Symbols represent the point estimates and lines are joining those together.
This example also illustrates the use of a side panel (bottom side), to depict as text the number of observations used to compute the point estimate and variability, over time.

The example uses two colors with different luminosities, therefore will print with different grayscale levels on a B/W printer.
Example3Image
Click on figure for enlarged image
Example4Title Subject's profile of multiple lab parameters (Author: Susan Schwarz)
Example4Description This is a multi-panel, grouped line plot. The grouping variable here is the type of lab parameter. Each panel represents an individual subject. The x-axis represents the study day that the lab was measured and it is important to keep this scale consistent across each panel and to keep the scale appropriately spaced (1 unit represents the same difference across the scale). The y-axis represents the lab value divided by the upper limit of normal for the specific patient. The value is read as ‘times upper limit of normal’ where a value of 1 would mean that the result was normal. Any value above or below 1 would be considered above the upper limit or normal or below the upper limit of normal respectively. The tan shaded area represents those values that are < 1 time the upper limit of normal. This shaded band can easily be altered within the code.
Note that if grayscale is used, adjustment to the shading may be necessary.
Example4Image Figure_6_200.PNG
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References Schwartz, Susan. 2009 “Clinical Trial Reporting Using SAS/GRAPH® SG Procedures.” Proceedings of the SAS Global Forum 2009 Conference. Cary, NC: SAS Institute Inc. Available at http://support.sas.com/resources/papers/proceedings09/174-2009.pdf.
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Software Program SAS
Software

Graphical Parameters

CodeExample1 - Attachment lgplot_example01.sas
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CodeExample2 - Attachment lgplot_example02.sas
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CodeExample3 - Attachment* lgplot_example03.sas
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CodeExample4 - Attachment* lgplot_example04.sas
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Keywords longitudinal line confidence interval
Disclaimer The opinions expressed in this document are those of the author and may not represent the opinions of the U.S. Food and Drug Administration or other authors.
Permission Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF ERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT OLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Reference Image Example01rep.png
Topic attachments
I Attachment Action Size Date Who Comment
pngpng Example01.png manage 40.1 K 13 Sep 2011 - 08:47 FabriceBancken Example 1 of line plot
pngpng Example01rep.png manage 13.2 K 07 Oct 2011 - 10:00 FabriceBancken Representative example of line plot
pngpng Example01small.png manage 22.4 K 13 Sep 2011 - 08:52 FabriceBancken Example 1 of line plot (small)
pngpng Example02.png manage 44.1 K 13 Sep 2011 - 15:31 MaryBanach Example 02 of line plot
pngpng Example02small.png manage 25.8 K 13 Sep 2011 - 08:58 FabriceBancken Example 2 of line plot (small)
pngpng Example03.png manage 38.9 K 13 Sep 2011 - 15:31 MaryBanach Example 3 of line plot
pngpng Example03small.png manage 22.6 K 13 Sep 2011 - 09:01 FabriceBancken Example 3 of line plot (small)
Topic revision: r12 - 19 Jun 2012 - 13:44:45 - MaryBanach
 

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