The STDRATE Procedure

POPULATION Statement

POPULATION <options>;

The required POPULATION statement specifies the information in the study data set. You can specify the following options in the POPULATION statement:

EVENT=variable

specifies the variable for the number of events in the study data set.

GROUP <( group-options )> =variable

specifies the variable whose values identify the various populations. The GROUP= option is required when METHOD=MH and also applies when METHOD=DIRECT in the PROC STDRATE statement.

You can specify the following group-options:

EXPOSED=’group’

identifies the exposed group in the derivation of the attributable fraction. This option applies only when you specify METHOD=MH(AF). If you do not specify the EXPOSED= option, the first study population, as indicated by the ORDER= option, is treated as the exposed population.

ORDER=DATA | FORMATTED | INTERNAL

specifies the order in which the values of the variable are to be displayed. You can specify the following values for the ORDER= suboption:

DATA: sorts by the order in which the values appear in the input data set.
FORMATTED: sorts by their external formatted values.
INTERNAL: sorts by the unformatted values, which yields the same order that the SORT procedure does.

By default, ORDER=INTERNAL. For ORDER=FORMATTED and ORDER=INTERNAL, the sort order is machine-dependent.

POPEVENT=number

specifies the total number of events in the study data set. This option applies only when METHOD=INDIRECT is specified in the PROC STDRATE statement and the total number of events is not available in the study data set.

RATE <( MULT=c )> = variable

specifies the variable for the observed rate in the study data set. This option applies only when STAT=RATE is specified in the PROC STDRATE statement. The MULT=c suboption specifies a power of 10 constant c and requests that the rates per c population-time units be read from the data set. The default is the value of the MULT= suboption used in the STAT=RATE option in the PROC STDRATE statement.

RISK=variable

specifies the variable for the observed risk in the study data set. This option applies only when STAT=RISK is specified in the PROC STDRATE statement.

TOTAL=variable

specifies the variable for either the population-time (STAT=RATE) or the number of observations (STAT=RISK) in the study data set.