diff --git a/R/freq.R b/R/freq.R
index 36730c16..5fc966c9 100755
--- a/R/freq.R
+++ b/R/freq.R
@@ -251,6 +251,12 @@ frequency_tbl <- function(x,
       new_list <- list(0)
       for (i in 1:length(user_exprs)) {
         new_list[[i]] <- eval_tidy(user_exprs[[i]], data = x)
+        if (length(new_list[[i]]) == 1) {
+          if (is.character(new_list[[i]]) & new_list[[i]] %in% colnames(x)) {
+            # support septic_patients %>% freq("hospital_id")
+            new_list[[i]] <- x %>% pull(new_list[[i]])
+          }
+        }
         cols <- c(cols, as_label(user_exprs[[i]]))
       }
 
diff --git a/docs/index.html b/docs/index.html
index 8e236023..93b69ec0 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -232,13 +232,21 @@
 <div id="get-this-package" class="section level2">
 <h2 class="hasAnchor">
 <a href="#get-this-package" class="anchor"></a>Get this package</h2>
-<p>This package is available on the official R network (CRAN), which has a peer-reviewed submission process. Install this package in R with:</p>
+<div id="latest-released-version" class="section level4">
+<h4 class="hasAnchor">
+<a href="#latest-released-version" class="anchor"></a>Latest released version</h4>
+<p>This package is available <a href="https://cran.r-project.org/package=AMR">on the official R network (CRAN)</a>, which has a peer-reviewed submission process. Install this package in R with:</p>
 <div class="sourceCode" id="cb1"><pre class="sourceCode r"><code class="sourceCode r"><a class="sourceLine" id="cb1-1" data-line-number="1"><span class="kw"><a href="https://www.rdocumentation.org/packages/utils/topics/install.packages">install.packages</a></span>(<span class="st">"AMR"</span>)</a></code></pre></div>
 <p>It will be downloaded and installed automatically. For RStudio, click on the menu <em>Tools</em> &gt; <em>Install Packages…</em> and then type in “AMR” and press <kbd>Install</kbd>.</p>
+</div>
+<div id="latest-development-version" class="section level4">
+<h4 class="hasAnchor">
+<a href="#latest-development-version" class="anchor"></a>Latest development version</h4>
 <p>The latest and unpublished development version can be installed with (precaution: may be unstable):</p>
 <div class="sourceCode" id="cb2"><pre class="sourceCode r"><code class="sourceCode r"><a class="sourceLine" id="cb2-1" data-line-number="1"><span class="kw"><a href="https://www.rdocumentation.org/packages/utils/topics/install.packages">install.packages</a></span>(<span class="st">"devtools"</span>)</a>
 <a class="sourceLine" id="cb2-2" data-line-number="2">devtools<span class="op">::</span><span class="kw"><a href="https://www.rdocumentation.org/packages/devtools/topics/reexports">install_gitlab</a></span>(<span class="st">"msberends/AMR"</span>)</a></code></pre></div>
 </div>
+</div>
 <div id="get-started" class="section level2">
 <h2 class="hasAnchor">
 <a href="#get-started" class="anchor"></a>Get started</h2>
diff --git a/index.md b/index.md
index ea0434a3..13612a00 100644
--- a/index.md
+++ b/index.md
@@ -50,7 +50,9 @@ Developers
 
 ## Get this package
 
-This package is available on the official R network (CRAN), which has a peer-reviewed submission process. Install this package in R with:
+#### Latest released version
+
+This package is available [on the official R network (CRAN)](https://cran.r-project.org/package=AMR), which has a peer-reviewed submission process. Install this package in R with:
 
 ```r
 install.packages("AMR")
@@ -58,6 +60,7 @@ install.packages("AMR")
 
 It will be downloaded and installed automatically. For RStudio, click on the menu *Tools* > *Install Packages...* and then type in "AMR" and press <kbd>Install</kbd>.
 
+#### Latest development version
 
 The latest and unpublished development version can be installed with (precaution: may be unstable):
 ```r