id_attributes(
strategy_id,
n_strategies,
patient_id,
n_patients,
state_id = NULL,
n_states = NULL,
transition_id = NULL,
n_transitions = NULL,
time_id = NULL,
time_intervals = NULL,
n_times = NULL,
sample = NULL,
n_samples = NULL,
grp_id = NULL,
patient_wt = NULL
)

## Arguments

strategy_id |
A numeric vector of integers denoting the treatment strategy. |

n_strategies |
A scalar denoting the number of unique treatment strategies. |

patient_id |
A numeric vector of integers denoting the patient. |

n_patients |
A scalar denoting the number of unique patients. |

state_id |
A numeric vector of integers denoting the health state. |

n_states |
A scalar denoting the number of unique health states. |

transition_id |
A numeric vector denoting the
health state transition. This is only used for state transition models. |

n_transitions |
A scalar denoting the number of unique transitions. |

time_id |
A numeric vector of integers denoting a unique time interval. |

time_intervals |
A `data.table` denoting unique time intervals. Must
contain the columns `time_id` , `time_start` , and `time_stop` .
`time_start` is the starting time of an interval and `time_stop` is
the stopping time of an interval. Following the survival package,
time intervals are closed on the right and
open on the left (except in the final interval where `time_stop` is equal to
infinity). |

n_times |
A scalar denoting the number of time intervals. Equal to the
number of rows in `time_intervals` . |

sample |
A numeric vector of integer denoting the sample from the posterior
distribution of the parameters. |

n_samples |
A scalar denoting the number of samples. |

grp_id |
An optional numeric vector of integers denoting the subgroup. |

patient_wt |
An optional numeric vector denoting the weight to apply to each patient
within a subgroup. |

## Details

When using the ID variables to index input_mats, the sorting order
should be the same as specified in `expand.hesim_data()`

; that is,
observations must be sorted by prioritizing: (i) `strategy_id`

, (ii) `patient_id`

,
(iii) the health-related ID variable (either `state_id`

or `transition_id`

),
and (iv) `time_id`

. When using ID variables are used to index transformed parameter
objects and `sample`

is used for indexing, then observations must be sorted by
prioritizing: (i) `sample`

, (ii) `strategy_id`

, (iii) `patient_id`

,
(iv) the health-related ID variable, and (v) `time_id`

.

## See also