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Title: Liver Test Safety Panel Over Time, Baseline vs. On-study

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Title Liver Test Safety Panel Over Time, Baseline vs. On-study
Graph_Subgroup Labs Liver
Labs_Liver_Clinical_Question Baseline: 1. What are the changes and percent changes from baseline over time? ie are abnormal labl values a result of abnormal baseline or have values changed on study?,
Baseline: 2. Is there a temporal relationship between treatment and lab value?
Description This is a multi-panel, multi-laboratory parameter scatter plot of Liver Tests. The figure compares each subject’s normalized baseline value to their on-study or post-baseline lab value at 1 week, 3 months and 6 months. The x-axis represents the ‘times upper limit of normal’ (ULN) for the parameters graphed 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 of normal or below the upper limit of normal respectively. For instance, a value of 3 would be read as ‘3 times the upper limit of normal’. Upper limit of normal is calculated by dividing the standard result (variable ‘lbstresn’ in dataset) in numeric units by the standard high range limit (variable ‘lbstnrhi’ in dataset). Original units can be substituted if needed as the upper limit of normal is normalized (has no units). There are reference lines for the standard values of interest (2xULN, 1.5xULN and 1.0xULN for this example). The reference lines should be altered within the code to be appropriate for the specific parameters plotted. On the top section, the graph is paneled by the different liver function tests. The first y-axis is the on-study or post-baseline xuln value. It is important to note that similar scale for the xuln axes (both x and y) should be maintained. Also note the logarithmic scale of the axes. The secondary y-axis panels the graph by the visit.

One of the main clinical interpretations of this graphic is to determine if a population of subjects’ (i.e., specific treatment) lab values have increased (worsened in this case) since baseline. Utilizing the 45 degree reference line through each panel, an increase in lab parameter would be represented by any point above the 45 degree line. The farther the point moves toward the upper left quadrant, the larger the change from baseline. For this specific graphic, those patients with normal (<= 1 xuln) baseline values and post-baseline values of clinical concern (> 2 xuln) would appear in the top left box or quadrant.

*Please note that if it is possible to program the output so that each small panel is a square, that is more desirable (considering that the axes have similar units). This will aid in the interpretation.
Contributor/Email Robert Gordon (rgordon2@its.jnj.com)
Additional_Contributor_Info Created by Susan Schwartz from the SAS Institute
Background This graphic was created by Susan Schwartz at the SAS Institute and included in the following article. 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
Keywords Scatter plot, Liver Function Test, Panel, Baseline
References http://support.sas.com/resources/papers/proceedings09/174-2009.pdf
Datasets CDISC Datasets
CDISC_Data ADLBC
Data_Format Data set created within the code for this graphic. Additional code utilizes the CTSPedia lab dataset (ADLBC) as an additional example.
CLASSIFICATIONS

Graph_Type Scatterplot
Variable_Relationship Continuous versus Continuous
Data_Types Continuous
Special_Considerations Depending on the purpose of the graph, reference ranges will vary. The clinical researchers involved will know the appropriate ranges to use (normal range, toxicity grade, etc.) which often will depend on conventions used in the disease under study. It is important to specify these values and properly incorporate them into the code before producing a graphic for interpretation.
Code_Available Yes
Software Program SAS
Software

R-Code - Attachment

R-Code

SAS-Code - Attachment Gordon - Liver Panel - SAS Code
Stata-Code - Attachment

Stata-Code

Other Code - Attachment

Other Code

Disclaimer The views expressed within CTSpedia are those of the author and must not be taken to represent policy or guidance on the behalf of any organization or institution with which the author is affiliated.
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 Gordon_LiverTestSafety_200.png
Topic revision: r3 - 21 Jun 2012 - 11:04:03 - MaryBanach
 

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