[Method of dietary nutritional status assessment and its application in cohort study of nutritional epidemiology].

Minimizing the burden on study subjects and assessing the general dietary nutritional status as accurately as possible are the basis of a nutritional epidemiological cohort study in the general population. While introducing the main dietary nutrition assessment methods, this paper manly describes the basic contents and principles for the development of food frequency questionnaire, and briefly illustrates the problems and solutions for the development of area specific food frequency questionnaires by taking the example of Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) cohort study. Finally, discusses preliminarily the necessity and possibility of developing a national food frequency questionnaire.

[Characteristic analysis among MSM-users of the "Online HIV Acquisition Risk Assessment System" in Guangzhou].

Objective: To analyze the characteristics of levels related to the risk through self-evaluation system, among MSM users in Guangzhou, between 2015 and 2017. Methods: Between 2015 and 2017, data was collected from the users of a self-evaluation system network related to HIV infection, based on the previous 'HIV health risk appraisal model'. Information on risk factors was collected to calculate the scores and levels of risks and to estimate the incidence of HIV. Taking the reference of R value on risks as (R=0.9-1.1) in general population. The ones with very low risk, with low risk, moderate risk, high risk and very high risk were set as R≤0.5, 0.52.0, respectively. The scores of modifiable risk factors were compared with different subgroups of MSM. Results: A total of 4 601 MSM were involved in this study, with the following features presented as: aged 16-64 (28.38±7.11) years, proportions of residence from Guangzhou, Guangdong province or other provinces as 38.6%(1 776/4 601)、35.4%(1 629/4 601) and 26.0%(1 197/4 601), 59.6%(2 742/4 601) received bachelor or above degrees. 81.3%(3 741/4 601) of them claimed as having homosexual orientation. R values of risk level on very low risk, low risk level, moderate risk, high risk and very high risk appeared as 12.9%(594/4 601), 50.9%(2 342/4 601), 17.0%(783/4 601), 14.8%(682/4 601) and 4.3%(200/4 601), respectively. Scores of modifiable risk factors decreased year by year (P<0.05), among MSM in this study. In either of the groups that experiencing insertive or receptive sex, the ones with heterosexual orientation presented the highest scores of modifiable risk factors (P<0.05). Conclusions: The risk levels on HIV infections called for special attention among the users of the self-evaluation network system. Among the MSM that carrying either insertive or receptive sex role, the ones with heterosexual orientation had the highest risk levels and scores of modifiable risk factors in Guangzhou. Further study should be explored to better understand the causes of related risks.