| One of the best things about computers
is how they handle repetitive tasks. Show the computer how to
do something once, and it will do it a million times without the slightest
complaint. In FlowJo's Layout Editor, you
can create a layout based on graphs and statistics from one of your
samples. With a single click, you can ask it to produce the same
layout from all of the rest of your samples. Or any subset
that makes sense for your experiment.
There are a couple of terms that we use in this
explanation that are important to get clear from the start.
They are attribute and value. The keywords in an FCS
file are organized in attribute-value pairs. The attribute
is a the keyword that is found in most files. The second is
the value of that keyword in any given file. For example,
most files will contain, in their header, a $Date attribute, and
a value containing the date on which that sample was collected.
When we talk about iteration attribute we mean the attribute that
is changed for each frame of the stack that is generated, for instance
the date of the collection.
In advanced reporting, there is an additional feature
known as the discriminator. This field is the mechanism for
finding the correct sample, when more than one sample are collected
with the same iteration value. This is described in more detail
at the bottom of this page.
Generally, you would select a keyword that groups
sets of tubes into distinct units--for example, choosing a keyword
that connotes patient ID, tissue type, or experimental condition.
Then you can place multiple graphs from different tubes (from different
FCS files!) into the same layout and still generate a batch output.
For example, if you set the iteration attribute
to be the keyword "$Cells", where you have a Patient ID
entered into the $Cells keyword, then FlowJo will examine all of
the tubes in the current workspace, and generate a list of the unique
values of $Cells. These are then displayed in the "Iteration"
popup menu. By selecting any of these values from this menu,
FlowJo will change the current layout view to show graphs &
statistics drawn only from tubes with that value of the Iterator.
(By setting this popup menu to "Off", you are telling
FlowJo to use all of the original graphs that dragged and dropped
into the layout). This is the way in which you can build template
reports which select graphs and statistics from different tubes
and put them all on the same page, but retain the ability to batch
the outputs.
The most common case remains that where the iteration
attribute is the sample (by which we generally mean the tube run
through the cytometer, as opposed to the sample taken from the subject).
Iterating in the Layout Editor
The first thing to be aware of is what is the currently
active group in the Workspace window. This will be the selected
item in the top half of the window. This is important to know
because the current group will determine the set of samples, from
which the layout will be constructed.
Next you should look at the popup menu in the layout.
In most cases, you'll probably be iterating by sample, and the popup
will appear like this:
Changing the Iteration Value
There are several ways to change the iteration value.
You can use the popup menu in the layout editor window to show the
layout for any value in the current group. Alternately you
can use the up and down arrows to move to the previous or next values.
Setting the Iteration Attribute
If you want to edit the iteration attribute, then
select the command from the Layout menu called Iteration Options
This will bring up the following dialog box:

Iterate by Sample: FlowJo Batch processes through
each data file in the order that they are listed in the Workspace
window.
E.g., using one sample as an example, create a layout
of the graphs, statistics, lines, and boxes that you wish to see
in the report. When you click the Batch button, FlowJo goes through
each sample in the selected group and gathers the information (graphs
etc.) from each sample and creates a report.
Iterate by Panel: FlowJo Batch processes by Patient.
E.g., If you have three patients stained with a
Panel of stains (5 tubes stained with different reagents) you may
wish to make a report for each Patient that combines graphs and
statistics from different tubes. Using one Patient as an example,
create a layout of the graphs, statistics, lines, and boxes that
you wish to see in the report. The layout for this patient can be
composed of graphs and statistics from different tubes (data files).
Under Iteration Options dialog, click on the "Iterate by Panel"
option and select the number of tube in the Panel (for this example
= 5). When you click the Batch button, FlowJo goes through the tubes
from each patient in the selected group and gathers the information
(graphs etc.) from the correct tube from that patient and creates
a report.
Iterate by Keyword: FlowJo Batch processes by Iterator and Discriminator
keywords.
E.g., The Iterate by Keyword option provides the
ability to specify one or more discriminator keywords. These fields
provide the value that must stay constant, while the iteration attribute
changes through each of its successive values. For example, if you
have a ten mouse study, and for each mouse you collect three different
tissue types, then there would be thirty tubes in the experiment.
You want to produce a ten page report, showing the graphs and statistics
for each mouse, one per page. You've acquired the data such that
the mouse identifier is stored in the FCS file's $SMNO (sample
number) field, and the tissue type information is stored in the
$CELLS field. Set the field $SMNO to be the iteration attribute,
and the keyword $CELLS to be the discriminator.
Multiple sample Iteration
The Iteration Options also provide the ability to
specify one or more discriminator keywords. These fields
provide the value that must stay constant, while the iteration attribute
changes through each of its successive values. For example, if you
have a ten mouse study, and for each mouse you collect three different
tissue types, then there would be thirty tubes in the experiment.
You want to produce a ten page report, showing the graphs and statistics
for each mouse, one per page. You've acquired the data such that
the mouse identifier is stored in the FCS file's $SMNO (sample number)
field, and the tissue type information is stored in the $CELLS field.
Set the field $SMNO to be the iteration attribute, and the keyword
$CELLS to be the discriminator.
More than one discriminator can be defined if desired.
By selecting additional keywords in the popup menu, the string of
discriminators will be extended. To start over, choose the second
item in the menu, marked Select None. This empties the list. |