/**
  * gets patients without start date
  *
  * @return
  */
 public List<Patient> getPatientsWithoutStartDate() {
   List<Patient> patientsWithoutStartDate = new ArrayList<Patient>();
   DataQualityService dqs = ((DataQualityService) Context.getService(DataQualityService.class));
   List<Integer> patientIds = dqs.getPatientsWithoutStartDate();
   for (Integer patientId : patientIds) {
     patientsWithoutStartDate.add(getPatientById(patientId));
   }
   return patientsWithoutStartDate;
 }