Expose df in pool()

NEWS.md

@@ -1,5 +1,9 @@
 # rbmi (development version)
 
+## New Features
+- Expose `df` in the pooled output of `pool_internal_rubin()`
+- Add the `median(dfs)` fallback for varying d.f. (MMRM case)
+
 ## Bug Fixes
 * Added en-GB spell-check and a corresponding test to the package
 * Fixed numerous spelling errors and standardised nomenclature for missing not

R/pool.R

@@ -280,12 +280,7 @@ pool_internal.rubin <- function(results, conf.level, alternative, type, D) {
     dfs <- results$df
     alpha <- 1 - conf.level
 
-    v_com <- unique(dfs)
-
-    assert_that(
-        length(v_com) == 1,
-        msg = "Degrees of freedom should be consistent across all samples"
-    )
+    v_com <- if (length(unique(dfs)) == 1) unique(dfs) else median(dfs)
 
     res_rubin <- rubin_rules(
         ests = ests,
@@ -302,6 +297,7 @@ pool_internal.rubin <- function(results, conf.level, alternative, type, D) {
         pfun = pt,
         df = res_rubin$df
     )
+    ret$df <- res_rubin$df
 
     return(ret)
 }