Population modeling data set description

Data set structure

The data set structure contains for each subject measurements, dose regimen, covariates etc … i.e. all collected information. The data must be in the long format, i.e each line corresponds to one individual and one time point. Different type of information (dose, observation, covariate, etc) are recorded in different columns, which must be tagged with a column type (see below). The column types are very similar and compatible with the structure used by the Nonmem software (the differences are listed here).

 

Description of line-types

Depending on the information it contains, each line will be considered as (with exception of the header line):

  • dose-line: line that contains information about the dose’s regimen (and possibly also about covariates and regression variables)
  • response-line: line that contains an observation (and possibly also about covariates and regression variables)
  • both dose and response-line: line that contains information about both the dose regimen and an observation (and possibly also about covariates and regression variables)

The EVENT ID column-type can be used to enforce each line to be a dose or response line. Without EVENT ID column, the content of the AMOUNT, OBSERVATION and IGNORED OBSERVATION columns are used to assign lines as dose lines, response lines or both. A table summarizing all cases can be found here.

Changes with respect to the MonolixSuite2016R1 version:

In the MonolixSuite2016R1, a line could not be both a dose-line and a response-line. Two lines were necessary to define a dose information and a measure occurring at the same time. In particular, in the MonolixSuite2018R1 version, if there is a non null dose and a value in the response-column, we consider it as both dose and response. It was formerly considered as a response.

 

Description of column-types

The first line of the data set must be a header line, defining the names of the columns. The columns names are completely free. In the MonolixSuite applications, when defining the data, the user will be asked to assign each column to a column-type (see here for an example of this step). The column type will indicate to the application how to interpret the information in that column. The available column types are given below:

Column-types used for all types of lines:

Column-types used for response-lines:

Column-types used for dose-lines: