ABSTRACT
OBJECTIVE：To p rovide reference for th e development and application of the pediatric quality of life inventory （PedsQL）. METHODS ：Using“PedsQL”as keyword ，retrieved from foreign databases as Medline ，ScienceDirect，Cochrane Library，ISI Web of Science ，SpringerLink and Embase ，Chinese databases as CNKI ，Wanfang database ，VIP and SinoMed ， research literatures about the application of PedsQL at home and abroad were collected during Jan. 1999-Dec. 2019. RESULTS & CONCLUSIONS：A total of 2 117 literatures were included ，including 1 836 foreign literatures and 281 domestic literatures （242 in Chinese，39 in English ）. The number of published literatures was increasing year by year. PedsQL had a wide range of applications and divided into 4 main areas according to purpose ，including analysis of health influencing factors （63 items），assessment of diseases burden （1 720 items），evaluation of intervention measures （285 items），theoretical study of other scales （49 items）. The application of PedsQL in clinical trials had made fast progress ，but there were still some problems in China ，such as improper selection and use of the scale ，less application in pediatric clinical practice ，and insufficient evaluation of intervention measures. It is suggested that future researcher should consider both universality and disease specificity ，self-administered and parental surrogate version of PedsQL when selecting tools ，and apply PedsQL to perform routine clinical health-related quality of life screening to optimize the utilization efficiency of pediatric health 一 resources，and construct PedsQL mapping function based on Chinese population preference to realize the economic evaluation of drug intervention measures.
ABSTRACT
OBJECTIVE：To pro vide reference for reducing the error of Markov model in pharmacoeconomic evaluation. METHODS：Referring to foreign literatures ，the errors in Markov model were explained. The commonly used correction methods were introduced ：half-cycle correction ，trapezoidal rule ，Simpson’s 1/3 rule，Simpson’s 3/8 method and life table method and their implementation in Excel and TreeAge software. RESULTS & CONCLUSIONS ：The error of Markov model was caused by the discretization process and could be corrected by the within-cycle correction methods. Half-cycle correction ，was the most commonly used correction method and could be corrected by adding half of the results of the first cycle and subtracting half of the results of the last cycle. By trapezoidal rule ，the interval was represented by the mean value of the first end point value of the interval ，and the area of right trapezoid was the cummulative result. Simpson’s 1/3 rule and Simpson ’s 3/8 rule took another point in the interval on the basis of trapezoidal correction and the continuous curve where these three points were represented the whole curve. By life table method ，the person-years of survival was the product of the group distance of the age group and the mean value of the number of survivors of the age group and the next age group ，and the total person-years of survival was the sum of person-years of survival of each age group. In Excel ，the fuction was set according to the method principle to realize the correction ；in Tree Age software，the function expression of Init Rwd ，Inor Rwd and Final Rwd were set to realize the correction. When using Markov model for pharmacoeconomic evaluation ，if the selection of periodic correction method is based on the ease of modeling and the universality of application ，the trapezoid rule method is recommended ；based on the accuracy of results ，it is suggested to use Simpson’s 1/3 method，so as to improve the accuracy of Markov model.