Prepare data from tretspef+los_group results for displaying as summary table

Usage

compile_principal_los_data(
  results,
  measure,
  pod_lookup = get_principal_pods(),
  sites = NULL
)

results: A named list containing NHP results tables
measure: Either "admissions" or "beddays". The measure to focus on for the output table
pod_lookup: A tibble, or a function that returns a tibble, containing columns named activity_type_label, pod and pod_label. This provides friendly labels for POD variables in the data. pod is the key column used for joining to data tables.
sites: Either NULL (the default) or a vector of site codes to filter to. NULL means don't filter; include all sites present in the data

A filtered and sorted tibble of principal projections of results, by point of delivery and grouped length of stay