Comparison of two automatic blood pressure recorders and the mercury sphygomomanometer.

The Physiometrics automatic blood pressure recorder was compared with the mercury sphygmomanometer in 2200 children aged 5-14 years, each reexamined after 3 and 5 years; the Physiometrics recorder produced higher intrachild correlations. In trials we could transfer what were essentially Physiometrics readings into levels similar to mercury sphygmomanometric readings by filtering out the infrasonic frequency band. The Physiometrics USM-105 was compared with its successor, the Physiometrics SR-2, on 378 children aged 10-17 years. The SR-2 measured lower than the USM-105: 4.1 mm Hg systolic and 8.5 mm Hg diastolic; differences were larger in the younger children. Both in mean levels and correlations, SR-2 readings were closer to the mercury sphygmomanometer's than were USM-105 readings, except or diastolic SR-2 readings, which were farther below the mercury sphygomomanometer 4th-phase readings than the USM-105. However, the SR-2 readings are likely closer to the true diastolic pressure in children 13 years and older, although we did not measure pressures intraarterially. Disc readings for systolic pressures showed coefficients of correlation averaging 0.96 among (n = 168) and 0.98 within (n = 40) readers for both models, but diastolic readings showed marked improvement form USM-105 (0.73, 0.81) to SR-2 (0.91, 0.97). In many of the parameters observed, SR-2 constitutes an improvement over USM-105. Automatic recorders offer certain advantages for measuring blood pressure in large-scale epidemiologic studies.

Variability of total cholesterol concentrations in serum by repeated measurements in a large pediatric population--limitations of quality controls for laboratory analyses.

We evaluated the variability in total cholesterol concentrations in serum in a large population of children over a period of time, to help us discern the limitations in reliability of current clinical laboratory methods for its analysis. We analyzed sera from a population of approximately 4000 children over a four-year period, quality-control sera, pooled sera, and surveillance samples from the Centers for Disease Control over a seven-year period, with a Technicon AutoAnalyzer II. Two methods of correction were suggested to adjust deviations in yearly serum total cholesterol means: yearly screening data were corrected on the basis of monthly variability in pooled-serum determinations and on the basis of deviations from values suggested by the Centers for Disease Control. Both correction methods were insufficient. These changes occur very slowly, and unless there is close monitoring and frequent comparison with a known standard, changes in laboratory results still can occur.

Type A coronary-prone behavior pattern and cardiovascular risk factor variables in children and adolescents: the Bogalusa Heart Study.

The relationship between Total score from the Hunter-Wolf A-B Self-Rating Scale for children (and derived Factors) and several cardiovascular risk factor variables was observed in children ages 10-17 in a biracial community. After analysis, effects of age, weight and height were removed from the Total A-B score, each Factor score, and risk factor variable. Differences in risk factor variables were observed in relation to A-B, race and sex. For each sex-race group, the four Factor scores and Total score were ranked into quintiles. Children in the upper quintile referred to as Type A children and those in the lower quintile, Type B. For Factor 1, which describes eagerness and energy in children (Eagergy), significant mean differences were found for serum total, beta- and pre-beta-lipoprotein cholesterol and triglycerides. In each instance, children classified as Type A exhibited approximately 10 mg/dl higher readings, except for pre-beta-lipoprotein cholesterol in which a 2 mg/dl difference was noted. Two significant second order interactions were found for systolic and diastolic blood pressure. Black boys who scored in the A direction had higher systolic blood pressures, while Type A girls had higher diastolic blood pressures than their Type B counterparts (p less than 0.05). For Factor IV, which is related to feeling hurried, there was an approximate 10 mg/dl difference in serum total and beta-lipoprotein cholesterol in the direction opposite to that predicted. Although the relationships between A-B coronary behavior pattern and risk factor variables in children are of low magnitude, the relationships are being observed in the direction that might be predicted. Measurement of Type A in children requires further refinement in concept identification and valid measurement.

The interaction of cigarette smoking, oral contraceptive use, and cardiovascular risk factor variables in children: the Bogalusa Heart Study.

Two separate surveys were conducted in a total biracial population of children ages 8-17 years to determine the effects of cigarette smoking and oral contraceptive use on blood pressure and serum lipids and lipoproteins. Information regarding smoking habits and oral contraceptive use was obtained from detailed questionnaires. For White boys and White and Black girls, a small but statistically significant decrease in diastolic blood pressure levels for cigarette smokers when compared to non-smokers was noted. A significant increase among cigarette smokers in beta-lipoprotein cholesterol, pre-beta-lipoprotein cholesterol, and triglycerides as well as a decrease in alpha-lipoprotein cholesterol was noted, especially for White girls. This change in lipoprotein levels for cigarette smokers was noted in both surveys. Oral contraceptive users had higher total cholesterol and beta-lipoprotein cholesterol and lower alpha-lipoprotein cholesterol than nonusers. After adjusting for oral-contraceptive use, particularly among White girls, cigarette smokers still demonstrated high pre-beta-lipoprotein cholesterol and lower alpha-lipoprotein cholesterol levels than non-smokers. These results suggest that the lipid and lipoprotein response to cigarette smoking and oral contraceptive use is to increase cardiovascular risk.

Factor analytic study of the Piers-Harris Children's Self-Concept Scale.

A factor analysis of the Piers-Harris Self-Concept Scale was conducted with a biracial u sample of children over a wide age range. The Scale was completed by 348 10-17 year old students in a rural community. Seven factors of 10 had sufficient item loadings to be interpretable. Six matched those found in the manual and an additional factor was found relating to Aggression. Race, sex, and age relationships are also reported for these seven factors.

Validation of a measure of type A behavior pattern in children: Bogalusa heart study.

A self-administered rating scale was developed to assess type A behavior in children. It contains 24 items (7-point scale) thought to reflect the major components of type A behavior. The scale was judged to be reliable and yielded the following factors: eagergy (eagerness-energy), restlessness-aggression, leadership, and alienation. 6 tasks were designed (reading, eating, walking, competition, time estimation, and crossing out number) to validate this new measure. A total of 160 predominantly middle-class public school fifth- and sixth-grade children participated in the following factorial design: 2 (classification-type A and type B) X 2 (condition-control and experimental) X 2 (sex-male and female) X 2 (race-white and black). Type A children performed in a more accelerated or intense manner than did type B children on 5 of the 6 tasks (only females exhibited rapid time estimation) as predicted. Also, children performed in a more accelerated or intense manner if they task instructions emphasized speed or intensity for 3 of the tasks (reading, crossing out number, and walking measures). Sex and race differences are also reported. Partial support is provided for the validity and reliability of this new measure.