private VPlanLeaf createLeafWithOrdinalTransformer(SampleAggregationMode aggregationMode) {
VPlanLeaf leaf = new VPlanLeaf();
// create simple transformer
OrdinalTransformer ordinalTrans = new OrdinalTransformer();
Map<String, TargetValueObject> mapping = new HashMap<String, TargetValueObject>();
TargetValueObject tv0 = new TargetValueObject();
TargetValueObject tv1 = new TargetValueObject();
tv0.setValue(5);
tv1.setValue(1);
mapping.put("Y", tv0);
mapping.put("N", tv1);
ordinalTrans.setMapping(mapping);
leaf.setTransformer(ordinalTrans);
// set scale
OrdinalScale ordinalScale = new OrdinalScale();
ordinalScale.setRestriction("Yes/No");