check_box

I am sure this is a trivial problem for a rails guru!

all I want to do is display an appropriately cheched check_box in a
table, so:

instead of
<% for t in @patient.histories%>

  <tr>
    <td><%= t.ihd %></td>
       </tr>
<%end%>

I want something like:

<% for t in @patient.histories%>

  <tr>
  <td><%=check_box_tag"diabetes", t.ihd %></td>
       </tr>
<%end%>

(hope that makes sense!)
I have tried many permutations of the above and I can't make it work!
All ideas gratefully recieved!