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Adds a Parameter for Derived RR (an ECG measurement)

Source: R/derive_param_rr.R
derive_param_rr.Rd

Adds a record for derived RR based on heart rate for each by group (e.g., subject and visit) where the source parameters are available.

Note: This is a wrapper function for the more generic derive_param_computed().

The analysis value of the new parameter is derived as $$\frac{60000}{HR}$$

Usage 

derive_param_rr(
  dataset,
  by_vars,
  set_values_to = exprs(PARAMCD = "RRR"),
  hr_code = "HR",
  get_unit_expr,
  filter = NULL
)

Arguments

dataset

Input dataset

The variables specified by the by_vars argument are expected to be in the dataset. PARAMCD, and AVAL are expected as well.

The variable specified by by_vars and PARAMCD must be a unique key of the input dataset after restricting it by the filter condition (filter argument) and to the parameters specified by hr_code.

Default value

none

by_vars

Grouping variables

For each group defined by by_vars an observation is added to the output dataset. Only variables specified in by_vars will be populated in the newly created records.

Permitted values

list of variables created by exprs(), e.g., exprs(USUBJID, VISIT)

Default value

none

set_values_to

Variables to be set

The specified variables are set to the specified values for the new observations. For example exprs(PARAMCD = "MAP") defines the parameter code for the new parameter.

Permitted values

List of variable-value pairs

Default value

exprs(PARAMCD = "MAP")

hr_code

HR parameter code

The observations where PARAMCD equals the specified value are considered as the heart rate assessments.

Permitted values

character value

Default value

"HR"

get_unit_expr

An expression providing the unit of the parameter

The result is used to check the units of the input parameters.

Permitted values

An expression which is evaluable in the input dataset and results in a character value

Default value

none

filter

Filter condition

The specified condition is applied to the input dataset before deriving the new parameter, i.e., only observations fulfilling the condition are taken into account.

Comparing derived numeric variables to fixed values, e.g., PCHG <= -90, may give unexpected results due to floating point representation. For details and solutions see the "Floating Point Comparisons" section in vignette("concepts_conventions").

Permitted values

an unquoted condition, e.g., AVISIT == "BASELINE"

Default value

NULL

Value

The input dataset with the new parameter added. Note, a variable will only be populated in the new parameter rows if it is specified in by_vars.

See also

compute_rr()

BDS-Findings Functions for adding Parameters/Records: default_qtc_paramcd(), derive_basetype_records(), derive_expected_records(), derive_extreme_event(), derive_extreme_records(), derive_locf_records(), derive_param_bmi(), derive_param_bsa(), derive_param_computed(), derive_param_doseint(), derive_param_exist_flag(), derive_param_exposure(), derive_param_framingham(), derive_param_map(), derive_param_qtc(), derive_param_wbc_abs(), derive_summary_records()

Examples 

library(tibble)

adeg <- tribble(
  ~USUBJID, ~PARAMCD, ~PARAM, ~AVAL, ~AVALU, ~VISIT,
  "01-701-1015", "HR", "Heart Rate", 70.14, "beats/min", "BASELINE",
  "01-701-1015", "QT", "QT Duration", 370, "ms", "WEEK 2",
  "01-701-1015", "HR", "Heart Rate", 62.66, "beats/min", "WEEK 1",
  "01-701-1015", "RR", "RR Duration", 710, "ms", "WEEK 2",
  "01-701-1028", "HR", "Heart Rate", 85.45, "beats/min", "BASELINE",
  "01-701-1028", "QT", "QT Duration", 480, "ms", "WEEK 2",
  "01-701-1028", "QT", "QT Duration", 350, "ms", "WEEK 3",
  "01-701-1028", "HR", "Heart Rate", 56.54, "beats/min", "WEEK 3",
  "01-701-1028", "RR", "RR Duration", 842, "ms", "WEEK 2"
)

derive_param_rr(
  adeg,
  by_vars = exprs(USUBJID, VISIT),
  set_values_to = exprs(
    PARAMCD = "RRR",
    PARAM = "RR Duration Rederived (ms)",
    AVALU = "ms"
  ),
  get_unit_expr = AVALU
)
#> # A tibble: 13 × 6
#>    USUBJID     PARAMCD PARAM                        AVAL AVALU     VISIT   
#>    <chr>       <chr>   <chr>                       <dbl> <chr>     <chr>   
#>  1 01-701-1015 HR      Heart Rate                   70.1 beats/min BASELINE
#>  2 01-701-1015 QT      QT Duration                 370   ms        WEEK 2  
#>  3 01-701-1015 HR      Heart Rate                   62.7 beats/min WEEK 1  
#>  4 01-701-1015 RR      RR Duration                 710   ms        WEEK 2  
#>  5 01-701-1028 HR      Heart Rate                   85.4 beats/min BASELINE
#>  6 01-701-1028 QT      QT Duration                 480   ms        WEEK 2  
#>  7 01-701-1028 QT      QT Duration                 350   ms        WEEK 3  
#>  8 01-701-1028 HR      Heart Rate                   56.5 beats/min WEEK 3  
#>  9 01-701-1028 RR      RR Duration                 842   ms        WEEK 2  
#> 10 01-701-1015 RRR     RR Duration Rederived (ms)  855.  ms        BASELINE
#> 11 01-701-1015 RRR     RR Duration Rederived (ms)  958.  ms        WEEK 1  
#> 12 01-701-1028 RRR     RR Duration Rederived (ms)  702.  ms        BASELINE
#> 13 01-701-1028 RRR     RR Duration Rederived (ms) 1061.  ms        WEEK 3