diff --git a/R/data_to_wide.R b/R/data_to_wide.R
index b88f17303..208612bac 100644
--- a/R/data_to_wide.R
+++ b/R/data_to_wide.R
@@ -17,6 +17,8 @@
 #' @param names_from The name of the column in the original data whose values
 #' will be used for naming the new columns created in the widened data. Each
 #' unique value in this column will become the name of one of these new columns.
+#' In case `names_prefix` is provided, column names will be concatenated with
+#' the string given in `names_prefix`.
 #' @param names_prefix String added to the start of every variable name. This is
 #'  particularly useful if `names_from` is a numeric vector and you want to create
 #'  syntactic variable names.
@@ -44,8 +46,8 @@
 #' single row, with each measurement stored in a separate column. Thus, the
 #' necessary information for `data_to_wide()` is:
 #'
-#' - The name of the column that identifies the groups or repeated measurements
-#'   (`by`).
+#' - The name of the column(s) that identify the groups or repeated measurements
+#'   (`by`, resp. its alias `id_cols`).
 #' - The name of the column whose _values_ will become the new column names
 #'   (`names_from`). Since these values may not necessarily reflect appropriate
 #'   column names, you can use `names_prefix` to add a prefix to each newly
@@ -53,7 +55,7 @@
 #' - The name of the column that contains the values (`values_from`) for the
 #'   new columns that are created by `names_from`.
 #'
-#' In other words: Repeated measurements, as indicated by `by`, that are
+#' In other words: repeated measurements, as indicated by `by`, that are
 #' saved into the column `values_from` will be spread into new columns, which
 #' will be named after the values in `names_from`. See also 'Examples'.
 #'
diff --git a/man/data_to_wide.Rd b/man/data_to_wide.Rd
index 80e094929..435ce649f 100644
--- a/man/data_to_wide.Rd
+++ b/man/data_to_wide.Rd
@@ -51,7 +51,9 @@ the values used to fill the new columns created in the widened data.}
 
 \item{names_from}{The name of the column in the original data whose values
 will be used for naming the new columns created in the widened data. Each
-unique value in this column will become the name of one of these new columns.}
+unique value in this column will become the name of one of these new columns.
+In case \code{names_prefix} is provided, column names will be concatenated with
+the string given in \code{names_prefix}.}
 
 \item{names_sep}{If \code{names_from} or \code{values_from} contains multiple variables,
 this will be used to join their values together into a single string to use
@@ -89,8 +91,8 @@ stored in multiple rows. The wide format stores the same information in a
 single row, with each measurement stored in a separate column. Thus, the
 necessary information for \code{data_to_wide()} is:
 \itemize{
-\item The name of the column that identifies the groups or repeated measurements
-(\code{by}).
+\item The name of the column(s) that identify the groups or repeated measurements
+(\code{by}, resp. its alias \code{id_cols}).
 \item The name of the column whose \emph{values} will become the new column names
 (\code{names_from}). Since these values may not necessarily reflect appropriate
 column names, you can use \code{names_prefix} to add a prefix to each newly
@@ -99,7 +101,7 @@ created column name.
 new columns that are created by \code{names_from}.
 }
 
-In other words: Repeated measurements, as indicated by \code{by}, that are
+In other words: repeated measurements, as indicated by \code{by}, that are
 saved into the column \code{values_from} will be spread into new columns, which
 will be named after the values in \code{names_from}. See also 'Examples'.
 }