
LEFTCENSORED  LC=variablename
LEFTCENSORED  LC=number

specifies the leftcensoring variable or a global leftcensoring limit.
You can use the variablename argument to specify a data set variable that contains the leftcensoring limit. If the value of this variable is missing,
then PROC SEVERITY assumes that such observations are not leftcensored.
Alternatively, you can use the number argument to specify a leftcensoring limit value that applies to all the observations in the data set. This limit must be
a nonzero positive number.
By the definition of leftcensoring, an exact value of the response is not known when it is less than or equal to the leftcensoring
limit. If you specify the response variable and the value of that variable is less than or equal to the value of the leftcensoring
limit for some observations, then PROC SEVERITY treats such observations as leftcensored and the value of the response variable
is ignored. If you specify the response variable and the value of that variable is greater than the value of the leftcensoring
limit for some observations, then PROC SEVERITY assumes that such observations are not leftcensored and the value of the
leftcensoring limit is ignored.
If you specify both rightcensoring and leftcensoring limits, then the leftcensoring limit must be greater than or equal
to the rightcensoring limit. If both limits are identical, then the observation is assumed to be uncensored.
For more information about leftcensoring, see the section Censoring and Truncation.

LEFTTRUNCATED  LT=variablename <(lefttruncationoption)>
LEFTTRUNCATED  LT=number <(lefttruncationoption)>

specifies the lefttruncation variable or a global lefttruncation threshold.
You can use the variablename argument to specify a data set variable that contains the lefttruncation threshold. If the value of this variable is missing
or 0 for some observations, then PROC SEVERITY assumes that such observations are not lefttruncated.
Alternatively, you can use the number argument to specify a lefttruncation threshold that applies to all the observations in the data set. This threshold must
be a nonzero positive number.
It is assumed that the response variable contains the observed values. By the definition of lefttruncation, you can observe
only a value that is greater than the lefttruncation threshold. If a response variable value is less than or equal to the
lefttruncation threshold, a warning is printed to the SAS log, and the observation is ignored. For more information about
lefttruncation, see the section Censoring and Truncation.
You can specify the following lefttruncationoption for an alternative interpretation of the lefttruncation threshold:

PROBOBSERVED  POBS=number

specifies the probability of observability, which is defined as the probability that the underlying severity event is observed
(and recorded) for the specified leftthreshold value.
The specified number must lie in the (0.0, 1.0] interval. A value of 1.0 is equivalent to specifying that there is no lefttruncation, because
it means that no severity events can occur with a value less than or equal to the threshold. If you specify value of 1.0,
PROC SEVERITY prints a warning to the SAS log and proceeds by assuming that LEFTTRUNCATED= option is not specified.
For more information, see the section Probability of Observability.

RIGHTCENSORED  RC=variablename
RIGHTCENSORED  RC=number

specifies the rightcensoring variable or a global rightcensoring limit.
You can use the variablename argument to specify a data set variable that contains the rightcensoring limit. If the value of this variable is missing,
then PROC SEVERITY assumes that such observations are not rightcensored.
Alternatively, you can use the number argument to specify a rightcensoring limit value that applies to all the observations in the data set. This limit must be
a nonzero positive number.
By the definition of rightcensoring, an exact value of the response is not known when it is greater than or equal to the
rightcensoring limit. If you specify the response variable and the value of that variable is greater than or equal to the
value of the rightcensoring limit for some observations, then PROC SEVERITY treats such observations as rightcensored and
the value of the response variable is ignored. If you specify the response variable and the value of that variable is less
than the value of the rightcensoring limit for some observations, then PROC SEVERITY assumes that such observations are not
rightcensored and the value of the rightcensoring limit is ignored.
If you specify both rightcensoring and leftcensoring limits, then the leftcensoring limit must be greater than or equal
to the rightcensoring limit. If both limits are identical, then the observation is assumed to be uncensored.
For more information about rightcensoring, see the section Censoring and Truncation.

RIGHTTRUNCATED  RT=variablename
RIGHTTRUNCATED  RT=number

specifies the righttruncation variable or a global righttruncation threshold.
You can use the variablename argument to specify a data set variable that contains the righttruncation threshold. If the value of this variable is missing
for some observations, then PROC SEVERITY assumes that such observations are not righttruncated.
Alternatively, you can use the number argument to specify a righttruncation threshold that applies to all the observations in the data set. This threshold must
be a nonzero positive number.
It is assumed that the response variable contains the observed values. By the definition of righttruncation, you can observe
only a value that is less than or equal to the righttruncation threshold. If a response variable value is greater than the
righttruncation threshold, a warning is printed to the SAS log, and the observation is ignored. For more information about
righttruncation, see the section Censoring and Truncation.