Reference Interval for Body Mass Index, And Vital Signs for Infants, Children, Adolescents, Adults and Geriatric Population of Taita-Taveta County, Kenya

Vital signs including temperature, pulse and respiratory rate, blood pressure, peripheral oxygen saturation, pain, level of consciousness and urine output are used to assess changes in a patient’s condition, and early signs of clinical deterioration so that treatment can be initiated to correct the associated disease. They are affected by factors such as age, sex, dietary habits, lifestyle, geographical location, socioeconomic status, health status, medications, ethnicity, genetics, and environment. The aim of this study was to establish 95% reference intervals for three vital signs for Taita-Taveta County Kenyan population. This cross-sectional study was conducted in the Department of Clinical Chemistry, Moi Subcounty Hospital, Taita-Taveta County, Voi, Kenya between May 2015 and December 2017 and involved 191 males and 317 females for vital signs study, and 125 males and 127 females for BMI study. The age of the referents population was 1-95 years. Vital signs were measured using automatic Mindray monitor and BMI was measured by weighing (kg) each referent individual and taking their height (in metres). Reference intervals were developed using EP28A3c guidelines. Mann-Whitney U test was used to develop reference intervals between males and females, and ANOVA and post-ANOVA test was used to compare the effect of age. Data was analyzed using SPSS software version 20. The developed reference intervals for BMI and the vital signs for Taita-Taveta County Kenyan population were different from those reported in medical literature; thus supporting the need for every clinical chemistry laboratory to develop their own reference intervals using their own population.