Comparative study on validation of electronic sphygmomanometers and mercury sphygmomanometers in Chinese children and adolescents

Objective To assess the accuracy of electronic sphygmomanometers ( ES ) in Chinese children and adoles- cents by comparing the blood pressure ( BP ) results obtained using ES and mercury sphygmomanometers ( MS ) . Methods A total of 1695children and adolescents aged 3-17 were recruited by using stratified cluster sampling method from both urban and suburban areas in Beijing in 2010. The population of each age group was at least 100 , evenly composed of boys and girls. Their living behaviors were investigated by questionnaires.The height , body weight and waist circumference were measured. ES ( Omron HEM-759P ) and MS were used to measure BP twice , respectively , and two instruments were used by turns. BP and pulse were recorded.Korotkoff K1 was recorded as systolic BP measured by MS ( mSBP ), K 4 and K 5 as diastolic BP by MS ( mDBP4and mDBP5 ), respectively.Systol-ic BP and diastolic BP measured by ES were recorded as eSBP and eDBP.The results from the two measurement methods were compared and the consistency was tested by Bland-Altman. Results A total of 1695children and ad- olescence at the age of three to seventeen was enrolled in the investigation , and each age group had almost the same population. The ratio of boys to girls was 0.99.Though the measurement results of both eSBP and mSBP of each age group were different from each other , most of eSBP results were higher than those of mSBP. Between ES andMS , the percentages of systolic pressure difference-values ( D-values ) modulus which were no more than 5 , 10and 15mm Hg were 54.2% , 82.9% , and 100% , respectively. When estimated by MS Korotcoff Ⅳ ( K 4 ), the per-centages of modulus which were no more than 5 , 10 , and 15mm Hg of diastolic pressure D-values measured by ES and MS were respectively 42.3% , 70.4%and 87.2% , respectively.When estimated by MS Korotcoff Ⅴ ( K 5 ), the percentages were 46.1% , 70.6%and 84.8%. After the adjustment of gender and age , the partial correlation coef-ficients of the systolic pressure between ES and MS , the diastolic pressure between eSBP and K 4 , and the diastolic pressure between mSBP and K 5 were respectively 0.716 , 0.448 , and 0.353 , respectively ( P0.01 ) .The analysis of Bland-Altman plots showed that the limit of 95% consistency of D-value between MS and ES , eSBP and K 4 , as well as mSBP and K 5 were respectively -13.5-19.6 , -22.5-15.1 , and -20.3-28.4mm Hg , respectively. Conclusion The measurement results of ES are higher than those of MS , but both of them are relatively stable and consistent. ES can be used in field survey for children and adolescents'blood pressure.