I have this Radio button code,

PHP Code:
<td width="16%" align="right">Bus Stop  : &nbsp;</td>
      <td width="16%" align="center">
      <input type="radio" name="vh_3R9" value="1"
      <? echo ($item_details['vh_3R9']=='1') ? "checked":""?>>
      <span style="COLOR: rgb(96,191,0); FONT-WEIGHT: bold">Yes</span>
      <input type="radio" name="vh_3R9" value="0"
      <? echo ($item_details['vh_3R9']=='0') ? "checked":""?>>
      <span style="COLOR: rgb(255,0,0); FONT-WEIGHT: bold">No</span>
    </td>
that I wanting to change to a Check Box,

PHP Code:
<td width="16%" align="right">Bus Stop : &nbsp;</td>
    <td width="16%" align="left">
    <input type="checkbox" name="vh_3R9" value="1" 
    <? echo ($item_details['vh_3R9']==1) ? 'checked' ''?>/>
    </td>
yet it is not working correctly,

all help appreciated