Appropriate data sources are the cornerstone of pharmacoepidemiological research.Based on the Guide on Methodological Standards in Pharmacoepidemiology in China(2nd edition),hereinafter referred to as"the Guideline(2nd edition)",this article provides an in-depth interpretation of the classification and selection of data sources in pharmacoepidemiological research.It begins with a brief overview of the evolution of data sources in pharmacoepidemiological studies,followed by a detailed analysis of the definitions,applicable scopes,conditions of use,and strengthens and limitations of primary and secondary data sources.It further introduces the characteristics of common data sources and relevant classic domestic and international databases.Subsequently,integrating aspects of the Guideline(2nd edition),including research questions,study design,study population,sample size,exposure or intervention,outcomes,and covariates,the article discusses the criteria and strategies for choosing data sources in pharmacoepidemiological research.Ultimately,a data source selection methodology is established based on clear classification,guided by research questions,tailored to research methods,and supported by data quality,aiming to promote the development of high-quality pharmacoepidemiological research in China.

Appropriate data sources are the cornerstone of pharmacoepidemiological research.Based on the Guide on Methodological Standards in Pharmacoepidemiology in China(2nd edition),hereinafter referred to as"the Guideline(2nd edition)",this article provides an in-depth interpretation of the classification and selection of data sources in pharmacoepidemiological research.It begins with a brief overview of the evolution of data sources in pharmacoepidemiological studies,followed by a detailed analysis of the definitions,applicable scopes,conditions of use,and strengthens and limitations of primary and secondary data sources.It further introduces the characteristics of common data sources and relevant classic domestic and international databases.Subsequently,integrating aspects of the Guideline(2nd edition),including research questions,study design,study population,sample size,exposure or intervention,outcomes,and covariates,the article discusses the criteria and strategies for choosing data sources in pharmacoepidemiological research.Ultimately,a data source selection methodology is established based on clear classification,guided by research questions,tailored to research methods,and supported by data quality,aiming to promote the development of high-quality pharmacoepidemiological research in China.

Established in 2017, the Screening Cohort for Asian Nomadic descendants in China (Scan-China) has benefited over 180,000 members of a multi-ethnic population, particularly individuals of Mongolian descent compared with the general population (Han ethnicity), in the Inner Mongolia Autonomous Region, China. This cohort study aims to evaluate the effectiveness of cancer screening and serve as a real-world data platform for cancer studies. The 6 most prevalent cancers in China are considered—namely, breast, lung, colorectal, gastric, liver and esophageal cancer. After baseline cancer risk assessments and screening tests, both active and passive follow-up (based on the healthcare insurance database, cancer registry, the front page of hospital medical records, and death certificates) will be conducted to trace participants’ onset and progression of cancers and other prevalent chronic diseases. Scan-China has preliminarily found a disproportionately lower screening participation rate and higher incidence/mortality rates of esophageal and breast cancer among the Mongolian population than among their Han counterparts. Further research will explore the cancer burden, natural history, treatment patterns, and risk factors of the target cancers.

Objective: To identify post-marketing active surveillance systems for vaccine safety around the world and understand their features and mechanisms, in order to provide guidance for vaccine administration activities in China. Methods: Following the steps of scoping review, literature about active surveillance system for vaccine safety and published by 30 June 2018 were identified by searching electronic databases, including PubMed, Scopus, and Cochrane Library. Grey literature were also sought by exploring relevant websites. Identified literature were screened according to eligibility criteria, and informative data from included literature were then charted. Framework Synthesis and Thematic Analysis were performed to integrate the charted data. Results: 97 pieces of literature were included for review, and 11 active surveillance systems for vaccine safety were identified, mostly located in developed countries. These systems were constructed by 3 types of organizations: administration departments, academic or research institutions, and health care providers. Their data sources included immunization registries, electronic medical records, claims data, case reports of adverse events following immunization electronic questionnaires, and epidemiologic study data. According to their operation procedures, these systems were grouped into 4 modes of active surveillance: Data Linkage, Investigator Network, Automatic Follow-up System, Studies Consortium. Conclusion Practice of active surveillance for vaccine safety greatly varies across countries, with different conditions and advantages. It is suggested that developing countries should choose suitable mode of active surveillance considering their local situations.

Objective To identify post?marketing active surveillance systems for vaccine safety around the world and understand their features and mechanisms, in order to provide guidance for vaccine administration activities in China. Methods Following the steps of scoping review, literature about active surveillance system for vaccine safety and published by 30 June 2018 were identified by searching electronic databases, including PubMed, Scopus, and Cochrane Library. Grey literature were also sought by exploring relevant websites. Identified literature were screened according to eligibility criteria, and informative data from included literature were then charted. Framework Synthesis and Thematic Analysis were performed to integrate the charted data. Results 97 pieces of literature were included for review, and 11 active surveillance systems for vaccine safety were identified, mostly located in developed countries. These systems were constructed by 3 types of organizations: administration departments, academic or research institutions, and health care providers. Their data sources included immunization registries, electronic medical records, claims data, case reports of adverse events following immunization electronic questionnaires, and epidemiologic study data. According to their operation procedures, these systems were grouped into 4 modes of active surveillance: Data Linkage, Investigator Network, Automatic Follow?up System, Studies Consortium. Conclusion Practice of active surveillance for vaccine safety greatly varies across countries, with different conditions and advantages. It is suggested that developing countries should choose suitable mode of active surveillance considering their local situations.

Objective To identify post?marketing active surveillance systems for vaccine safety around the world and understand their features and mechanisms, in order to provide guidance for vaccine administration activities in China. Methods Following the steps of scoping review, literature about active surveillance system for vaccine safety and published by 30 June 2018 were identified by searching electronic databases, including PubMed, Scopus, and Cochrane Library. Grey literature were also sought by exploring relevant websites. Identified literature were screened according to eligibility criteria, and informative data from included literature were then charted. Framework Synthesis and Thematic Analysis were performed to integrate the charted data. Results 97 pieces of literature were included for review, and 11 active surveillance systems for vaccine safety were identified, mostly located in developed countries. These systems were constructed by 3 types of organizations: administration departments, academic or research institutions, and health care providers. Their data sources included immunization registries, electronic medical records, claims data, case reports of adverse events following immunization electronic questionnaires, and epidemiologic study data. According to their operation procedures, these systems were grouped into 4 modes of active surveillance: Data Linkage, Investigator Network, Automatic Follow?up System, Studies Consortium. Conclusion Practice of active surveillance for vaccine safety greatly varies across countries, with different conditions and advantages. It is suggested that developing countries should choose suitable mode of active surveillance considering their local situations.

Objective To examine the associations between season of birth and factors as age at menarche,age at menopause and reproductive span.Methods A total of 285 186 female from the China Kadoorie Biobank,with complete data on critical variables and had menarche at 9-18 years old,were included.A total of 132 373 female with natural menopause were included for the analysis on age at menopause and reproductive span.Multiple linear regression models were used to assess the associations of birth season and the age at menarche,menopause,and reproductive span.Subgroup analyses were performed on birth cohorts and urban/rural residence.Results Compared with the Spring-born (March,April,and May),participants who were born in Summer (June,July,and August),Autumn (September,October,and November),and Winter (December,January,and February)appeared late on both age at menarche and menopause.Multivariable-adjusted coefficients (95％ CI)appeared as 0.14 (95％CI:0.13-0.16),0.26(95％CI:0.24-0.27),0.10 (95％CI:0.08-0.12) for age at menarche respectively and 0.14 (95％CI:0.08-0.20),0.18 (95％CI:0.12-0.24),0.09 (95％CI:0.03-0.16) for age at menopause respectively.No statistically significant association was found between the season of birth and reproductive span.The association was consistent between urban and rural residents and across the birth cohorts.Conclusions female born in spring showed both earlier age on both menarche and menopause,compared to the ones born in other seasons.Our findings suggested that exposures in early life with some degree of seasonal variation might influence the development of female reproductive system.