The Chinese version of the EQ-5D demonstrated acceptable construct validity and fair to moderate levels of test-retest reliability in an urban general population in China.

BackgroundChildhood obesity is a growing public health concern in China. It not only compromises physical health, but also has negative impacts on psychosocial well-being. As obesity rates increase, finding out what the perceptions of Chinese youth are regarding their weight is important for intervention planning and evaluation. However, there is a paucity of available obesity-specific instruments for children and adolescents in China and youth weight-specific quality of life (QOL) has been little reported. This study aimed to evaluate the measurement properties of the Chinese version of the Youth Quality of Life Instrument – Weight Module (YQOL-W).MethodsThe Chinese version of the YQOL-W was administered to 840 youth aged 11–18 from nine schools. Measurement properties including measurement model, reliability, validity and burden were evaluated.ResultsConfirmatory factor analysis showed that a three-factor model had acceptable model fit. The instrument had robust internal consistency reliability with Cronbach's α ranging from 0.84 to 0.96 and acceptable test-retest reliability with the intraclass correlation coefficients (ICCs) all higher than 0.7. The standard error of measurement (SEM) values for the Self, Social and Environment factors and total score were 10.352, 9.526, 12.086 and 8.425, respectively. The small real differences (SRDs) for the Self, Social and Environment factors and total score were 28.675, 26.387, 33.478, and 23.337, respectively. The Pearson's correlation coefficients between the YQOL-W and the PedsQL4.0 General Core Scales were stronger between comparable dimensions than those between less comparable dimensions, demonstrating convergent and discriminant evidence of construct validity. Significant differences were found in subscale and total scores across weight status, age and genders (P<0.01), supporting the known-groups validity of the instrument.ConclusionThe Chinese version of the YQOL-W has acceptable measurement properties and can be used to assess the weight-specific QOL of children and adolescents in China.

Targeted interventions designed to promote QOL and healthy weight control behaviors among youth may help to decrease the prevalence of smoking.

ObjectiveTo evaluate the quality of life (QOL) of overweight and obese middle or high school students and identify relevant factors influencing their QOL scores.Methods716 students were recruited from 6 middle or high schools in Hangzhou, China. The Chinese version of the Youth Quality of Life Instrument–Weight Module (YQOL-W) was self administered. The YQOL-W scores were compared among different BMI groups, gender, educational status, annual household income, parental education and recruitment community using t test or one-way analysis of variance. The independent association of these variables with QOL among overweight and obese students was examined using multivariable linear regression modeling.ResultsOverweight and obese students reported lower total scores, self, social and environment scores than their normal weight peers (all P<0.001). The QOL of overweight and obese middle and high school students was associated with BMI value, gender, educational status, parental education, and recruitment community. Girls had lower total scores, self, social and environment domain scores than boys (all P<0.001); high school students had lower total and three domain scores than middle school students (all P<0.05). Students whose fathers had higher education reported higher total scores, self and social scores than students with less educated fathers (all P<0.05). Students whose mothers had higher education reported higher environment scores than students with less educated mothers (P = 0.01). Students from migrant communities reported significantly lower total scores, self and social scores than those from rural communities (all P<0.05), but comparable scores with those from urban communities (P>0.05). Students from migrant communities reported comparable environment scores with those from rural and urban communities (P>0.05).ConclusionsOverweight and obesity have negative effects on students’ quality of life. Therefore weight specific QOL could be included in weight reduction interventions as a relevant outcome.

In parallel hybrid hydraulic excavator (PHHE) with super capacitor, the throttle position of the diesel engine is changed with the variation of the capacitor’s state of charge (SOC) of the super capacitor. When the throttle position is switched, the rotational speed of the diesel engine cannot be able to increase or decrease to the target speed rapidly enough, and it may fluctuate in large range under given conditions. Under the assumption that the loading torque of the diesel engine is invariant at the switch instant, the response of the rotational speed appears to be in different forms, which are not admitted for the normal work of PHHE. In this paper, switch types are divided into eight state-switch modes, in terms of the loading type and the amplitude of variation of the throttle position. And the paper mainly aims to the smooth transition of the rotational speed during the switched process of PHHE by the dynamic compensation of the electric motor. Experimental results show that the dynamic compensation of the electric motor can improve the dynamic behavior when PHHE is under state-switch modes.