Minoru Yamakado1, Kiyoshi Ichihara2, Yoshiyuki Matsumoto3, Yoshiki Ishikawa4, Kiminori Kato5, Yusuke Komatsubara3, Norihide Takaya6, Shohken Tomita7, Reo Kawano8, Keisuke Takada9, Kiyoaki Watanabe10. 1. Department of Nursing, Ashikaga Institute of Technology, 268-1 Ohmae-cho, Ashikaga, Tochigi 326-8558, Japan. 2. Department of Laboratory Sciences, Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube 755-8505, Japan. Electronic address: RXK03567@nifty.com. 3. National Federation of Health Insurance Societies, 1-24-4 Minamiaoyama, Minato-ku, Tokyo 107-8558, Japan. 4. Mizuho Health Insurance Society, Otemachi Medical Center, 1-5-5 Otemachi Chiyoda-ku, Tokyo 100-8176, Japan. 5. Department of Laboratory Medicine and Clinical Epidemiology for Prevention of Noncommunicable Diseases, Graduate School of Medical and Dental Sciences, Niigata University, 1-757 Asahimachi-dori, Chuo-ku, Niigata 951-8510, Japan. 6. Medical Corporation Doyukai, 1-15-10 Nishikata, Bunkyo-ku, Tokyo 113-0024, Japan. 7. Kansai Occupational Health Association, 3-1-1 Umeda, Kita-ku, Osaka 530-0001, Japan. 8. Department of Laboratory Sciences, Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube 755-8505, Japan; Clinical Research Center, Yamaguchi University Hospital, 1-1-1 Minamikogushi, Ube 755-8505, Japan. 9. Department of Laboratory Sciences, Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube 755-8505, Japan. 10. Tokyo Center for Laboratory Medicine, 6-3-17 Shimomeguro, Meguro-ku, Tokyo 153-0064, Japan.
Abstract
BACKGROUND: With nationwide standardization of laboratory tests among institutions for health screening in Japan, common reference intervals (RIs) were derived from records of 1,500,000 health check attendees. METHODS: Targets were 20 basic laboratory tests including body mass index (BMI) and systolic and diastolic blood pressures (SBP, DBP). Individuals fulfilling the following strict criteria were chosen: SBP<130, DBP<85mmHg, BMI<25kg/m(2), non-smoking, ethanol consumption<20g/day and under no mediation with no remarkable current/past illnesses. The latent abnormal values exclusion (LAVE) method was applied to ensure fully normal results. RIs were derived by parametric method using modified Box-Cox power transformation. RESULTS: Among all attendees, 23% fulfilled the criteria. Application of the LAVE method further reduced the dataset by 40%-50%. Age-related charts of test results differed greatly between genders in almost all tests. Comparison of derived RIs with clinical decision limits (CDLs) revealed that the upper limits of RIs differed from CDLs according to gender and age. CONCLUSIONS: Implementation of gender and age-specific RIs derived from individuals with fully normal health attributes will (1) enable appropriate interpretation of test results in health screening and (2) promote judicious application of CDLs for therapeutic intervention, taking into account gender, age and other health attributes.
BACKGROUND: With nationwide standardization of laboratory tests among institutions for health screening in Japan, common reference intervals (RIs) were derived from records of 1,500,000 health check attendees. METHODS: Targets were 20 basic laboratory tests including body mass index (BMI) and systolic and diastolic blood pressures (SBP, DBP). Individuals fulfilling the following strict criteria were chosen: SBP<130, DBP<85mmHg, BMI<25kg/m(2), non-smoking, ethanol consumption<20g/day and under no mediation with no remarkable current/past illnesses. The latent abnormal values exclusion (LAVE) method was applied to ensure fully normal results. RIs were derived by parametric method using modified Box-Cox power transformation. RESULTS: Among all attendees, 23% fulfilled the criteria. Application of the LAVE method further reduced the dataset by 40%-50%. Age-related charts of test results differed greatly between genders in almost all tests. Comparison of derived RIs with clinical decision limits (CDLs) revealed that the upper limits of RIs differed from CDLs according to gender and age. CONCLUSIONS: Implementation of gender and age-specific RIs derived from individuals with fully normal health attributes will (1) enable appropriate interpretation of test results in health screening and (2) promote judicious application of CDLs for therapeutic intervention, taking into account gender, age and other health attributes.
Authors: Abigail S A Bawua; Kiyoshi Ichihara; Rosemary Keatley; John Arko-Mensah; Yvonne Dei-Adomakoh; Patrick F Ayeh-Kumi; Rajiv Erasmus; Julius Fobil Journal: Int J Lab Hematol Date: 2020-09-03 Impact factor: 2.877