Main program (using properly setup object):

$moduleObject->findBestEvidence( $variable );

Module:
package Module;

sub new {
	my $class = shift;
	my $self = {
		'param' => "value",
	};
	bless($self, $class);
	return $self;
}
sub findBestEvidence {
      my $var = shift;
      $stew = "Whatever";
}
1;


Undefined subroutine &Module::findBestEvidence ....