Step 4: Obtain aggregated data on temporal symmetry

Introduction

In this vignette we will explore the functionality and arguments of summariseTemporalSymmetry() function. This function uses cdm$intersect introduced in the previous vignettes to produce aggregated statistics containing the frequency for different time gaps between the initiation of the marker and the initiation of the index (marker_date $-$index_date) and can be used to then help visulise the asymmetry between the index and marker cohorts. The work of this function is best illustrated via an example.

Recall that in the previous vignette, we’ve used cdm$aspirin and cdm$acetaminophen to generate cdm$intersect.

Obtaining temporal symmetry

summariseTemporalSymmetry(cohort = cdm$intersect, days = 30) |> 
  dplyr::glimpse()
#> Rows: 23
#> Columns: 13
#> $ result_id        <int> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,…
#> $ cdm_name         <chr> "GiBleed", "GiBleed", "GiBleed", "GiBleed", "GiBleed"…
#> $ group_name       <chr> "index_name &&& marker_name", "index_name &&& marker_…
#> $ group_level      <chr> "aspirin &&& amoxicillin", "aspirin &&& amoxicillin",…
#> $ strata_name      <chr> "overall", "overall", "overall", "overall", "overall"…
#> $ strata_level     <chr> "overall", "overall", "overall", "overall", "overall"…
#> $ variable_name    <chr> "temporal_symmetry", "temporal_symmetry", "temporal_s…
#> $ variable_level   <chr> "-390", "-360", "-330", "-300", "-270", "-240", "-180…
#> $ estimate_name    <chr> "count", "count", "count", "count", "count", "count",…
#> $ estimate_type    <chr> "integer", "integer", "integer", "integer", "integer"…
#> $ estimate_value   <chr> "1", "2", "1", "1", "2", "2", "3", "7", "2", "5", "4"…
#> $ additional_name  <chr> "overall", "overall", "overall", "overall", "overall"…
#> $ additional_level <chr> "overall", "overall", "overall", "overall", "overall"…

The default of the difference of two initiations is measured in 30 days. The estimate value is an aggregate count of how many individuals having the index happening after marker and having the marker happening after index in 30 day bins.

Modify days

Recall the default for the days is 30, one could also change this to other numerical numbers such as 7, 60, 90 days for example.

summariseTemporalSymmetry(cohort = cdm$intersect,
                          days = 60) |> 
  dplyr::glimpse()
#> Rows: 13
#> Columns: 13
#> $ result_id        <int> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
#> $ cdm_name         <chr> "GiBleed", "GiBleed", "GiBleed", "GiBleed", "GiBleed"…
#> $ group_name       <chr> "index_name &&& marker_name", "index_name &&& marker_…
#> $ group_level      <chr> "aspirin &&& amoxicillin", "aspirin &&& amoxicillin",…
#> $ strata_name      <chr> "overall", "overall", "overall", "overall", "overall"…
#> $ strata_level     <chr> "overall", "overall", "overall", "overall", "overall"…
#> $ variable_name    <chr> "temporal_symmetry", "temporal_symmetry", "temporal_s…
#> $ variable_level   <chr> "-420", "-360", "-300", "-240", "-180", "-120", "-60"…
#> $ estimate_name    <chr> "count", "count", "count", "count", "count", "count",…
#> $ estimate_type    <chr> "integer", "integer", "integer", "integer", "integer"…
#> $ estimate_value   <chr> "1", "3", "3", "2", "10", "7", "4", "5", "5", "4", "8…
#> $ additional_name  <chr> "overall", "overall", "overall", "overall", "overall"…
#> $ additional_level <chr> "overall", "overall", "overall", "overall", "overall"…

We will use the output from this function to then visulise the asymmetry between the index and marker in the next steps of the vignette.