diff --git a/R/pool_D4.R b/R/pool_D4.R
index d6193fb..090ecbf 100644
--- a/R/pool_D4.R
+++ b/R/pool_D4.R
@@ -49,7 +49,7 @@ pool_D4 <- function(data,
 {
   m <- nimp
   data <-
-    filter(data, data[impvar] <= nimp)
+    filter(data, data[[impvar]] <= nimp)
   
   if(model_type=="binomial") family="binomial"
   if(model_type=="linear") family="gaussian"
diff --git a/R/psfmi_lm_bw.R b/R/psfmi_lm_bw.R
index 98f6385..c936f51 100644
--- a/R/psfmi_lm_bw.R
+++ b/R/psfmi_lm_bw.R
@@ -112,7 +112,7 @@ psfmi_lm_bw <- function(data, nimp, impvar, Outcome, P, p.crit, method, keep.P)
         }
         if(method=="D4"){
           data <-
-            filter(data, data[impvar] <= nimp)
+            filter(data, data[[impvar]] <= nimp)
           imp_list <-
             data %>% group_split(data[, impvar], .keep = FALSE) %>%
             mitools::imputationList(imp_list)
diff --git a/R/psfmi_lm_fw.R b/R/psfmi_lm_fw.R
index 48c5b07..43eed99 100644
--- a/R/psfmi_lm_fw.R
+++ b/R/psfmi_lm_fw.R
@@ -124,7 +124,7 @@ psfmi_lm_fw <- function(data, nimp, impvar, Outcome, P, p.crit, method, keep.P)
         }
         if(method=="D4"){
           data <-
-            filter(data, data[impvar] <= nimp)
+            filter(data, data[[impvar]] <= nimp)
           imp_list <-
             data %>% group_split(data[, impvar], .keep = FALSE) %>%
             mitools::imputationList(imp_list)
diff --git a/R/psfmi_lr_bw.R b/R/psfmi_lr_bw.R
index 6da2b92..478bcf1 100644
--- a/R/psfmi_lr_bw.R
+++ b/R/psfmi_lr_bw.R
@@ -123,7 +123,7 @@ psfmi_lr_bw <- function(data, nimp, impvar, Outcome, P, p.crit, method, keep.P)
         }
         if(method=="D4"){
           data <-
-            filter(data, data[impvar] <= nimp)
+            filter(data, data[[impvar]] <= nimp)
           imp_list <-
             data %>% group_split(data[, impvar], .keep = FALSE) %>%
             mitools::imputationList(imp_list)
@@ -162,7 +162,7 @@ psfmi_lr_bw <- function(data, nimp, impvar, Outcome, P, p.crit, method, keep.P)
         }
         if(method=="D3"){
           data <-
-            filter(data, data[impvar] <= nimp)
+            filter(data, data[[impvar]] <= nimp)
           imp_list <-
             data %>% group_split(data[, impvar], .keep = FALSE) %>%
             mitools::imputationList(imp_list)
diff --git a/R/psfmi_lr_fw.R b/R/psfmi_lr_fw.R
index 5a987ca..5890a19 100644
--- a/R/psfmi_lr_fw.R
+++ b/R/psfmi_lr_fw.R
@@ -129,7 +129,7 @@ psfmi_lr_fw <- function(data, nimp, impvar, Outcome, P, p.crit, method, keep.P)
         }
         if(method=="D4"){
           data <-
-            filter(data, data[impvar] <= nimp)
+            filter(data, data[[impvar]] <= nimp)
           imp_list <-
             data %>% group_split(data[, impvar], .keep = FALSE) %>%
             mitools::imputationList(imp_list)