def to_model
      mps = preconditions.collect(&:to_model)
      HQMF::PopulationCriteria.new(id, hqmf_id, type, mps, title, aggregator, comments)
    end
def to_model
      mps = preconditions.collect(&:to_model)
      HQMF::PopulationCriteria.new(id, hqmf_id, type, mps, title, aggregator, comments)
    end
Generates this classes hqmf-model equivalent