The Minneapolis children's blood pressure study. Part 1: standards of measurement for children's blood pressure.

Among 9977 public school children 6 to 9 years of age who were screened in late winter and spring of 1978 in Minnesota, statistically significant effects of individual observers, room temperature, time of day, and season were found after adjusting for multiple variables. Systolic blood pressure (SBP) for all children was lower with warmer temperatures in the examination room, whereas diastolic blood pressure (DBP) was directly related to the room temperature, after adjustment for other factors significantly affecting the variability of blood pressure. Morning measurements were also lower than afternoon measurements for SBP but showed little difference for DBP. Problems of standardization for establishing blood pressure (BP) norms for children are discussed. (Hypertension 2 (suppl I): 1-18-1-24, 1980)