1. Department of Pediatrics, Graduate School of Medical Science Kyoto Prefectural University of Medicine Kyoto Japan
2. Department of Pediatrics Hananoki Medical Welfare Center Kyoto Japan
3. Department of Pediatric Cardiovascular Surgery, Graduate School of Medical Science Kyoto Prefectural University of Medicine Kyoto Japan
4. Department of Neonatology Japanese Red Cross Kyoto Daiichi Hospital Kyoto Japan
5. Department of Pediatrics National Hospital Organization Maizuru Medical Center Kyoto Japan
6. Department of Biostatistics, Graduate School of Medical Science Kyoto Prefectural University of Medicine Kyoto Japan