You can loop through all the check boxes with a condition inside the loop to check if the check box is true.
var checkBoxVariables = [];
checkBoxVariables[0] = 'check_box_variable_1';
checkBoxVariables[1] = 'check_box_variable_2';
checkBoxVariables[2] = 'check_box_variable_3';
checkBoxVariables[3] = 'check_box_variable_4';
var checkBoxLabels = [];
checkBoxLabels[0] = 'check_box_label_1';
checkBoxLabels[1] = 'check_box_label_2';
checkBoxLabels[2] = 'check_box_label_3';
checkBoxLabels[3] = 'check_box_label_4';
for(var i=0; i<checkBoxVariables.length; i++) {
if(producer[checkBoxVariables[i]] == 'true') {
current.description += '\n' + checkBoxLabels[i];
}
}
