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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 parameter) and to the parameters specified by hr_code.

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)

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

hr_code

HR parameter code

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

Permitted Values: character value

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: A variable of the input dataset or a function call

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.

Permitted Values: a condition

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.

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, "msec", "WEEK 2",
  "01-701-1015", "HR", "Heart Rate", 62.66, "beats/min", "WEEK 1",
  "01-701-1015", "RR", "RR Duration", 710, "msec", "WEEK 2",
  "01-701-1028", "HR", "Heart Rate", 85.45, "beats/min", "BASELINE",
  "01-701-1028", "QT", "QT Duration", 480, "msec", "WEEK 2",
  "01-701-1028", "QT", "QT Duration", 350, "msec", "WEEK 3",
  "01-701-1028", "HR", "Heart Rate", 56.54, "beats/min", "WEEK 3",
  "01-701-1028", "RR", "RR Duration", 842, "msec", "WEEK 2"
)

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