Monbouton.checked = marequeteDevrait fonctionner.
$q_PM = mysql_query("SELECT * FROM prejudicemateriel WHERE id_prejMat = '".$id."' ") or die(mysql_error());
$row_PM = mysql_fetch_assoc($q_PM);
echo '<table width="200" border="0">
<tr>
<td> <input type="radio"
name="nomduradio"
value="valueduradio"
<?php if($row_PM["pejudiceMateriels1"] == 1) { echo "checked=checked";} ?>
/></td>
</tr>
</table>';
echo '<table width="200" border="0">'; while ($row_PM = mysql_fetch_assoc($q_PM);) { echo '<tr><td>'; if($row_PM["pejudiceMateriels1"] == 1) { $chkd = "checked=checked"; }else{ $chkd = ""; } echo '<input type="radio" name="nomduradio" value="valueduradio" '.$chkd.'/>'; echo '</td></tr>'; } echo '</table>';