Real world study (RWS), a further verification and supplement for explanatory randomized controlled trial to evaluate the effectiveness of intervention measures in real clinical environment, has increasingly become the focus in the field of research on medical and health care services. However, some people mistakenly equate real world study with observational research, and argue that intervention and randomization cannot be carried out in real world study. In fact, both observational and experimental design are the basic designs in real world study, while the latter usually refers to pragmatic randomized controlled trial and registry-based randomized controlled trial. Other nonrandomized controlled and adaptive designs can also be adopted in the RWS.
Clinical Studies as Topic ; Humans ; Registries ; Research Design

Objective: To analyze the characteristics of super-antigen (SAg) of group A Streptococcus pyogenes (GAS), isolated from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. Methods: Throat swab specimens from patients with scarlet fever or pharyngeal infections were collected and tested for GAS. Eleven currently known SAg genes including SpeA, speC, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa were tested by real-time PCR while M protein genes (emm genes) were amplified and sequenced by PCR. Results: A total of 377 GAS were isolated from 6 801 throat swab specimens, with the positive rate as 5.5%. There were obvious changes noticed among speC, speG, speH and speK in three years. A total of 45 SAg genes profiles were observed, according to the SAgs inclusion. There were significant differences appeared in the frequencies among two of the highest SAg genes profiles between emm1 and emm12 strains (χ(2)=38.196, P<0.001; χ(2)=72.310, P<0.001). There also appeared significant differences in the frequencies of speA, speH, speI and speJ between emm1 and emm12 strains (χ(2)=146.154, P<0.001; χ(2)=52.31, P<0.001; χ(2)=58.43, P<0.001; χ(2)=144.70, P<0.001). Conclusions: Obvious changes were noticed among SAg genes including speC, speG, speH and speK from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. SAg genes including speA, speH, speI and speJ appeared to be associated with the emm 1 and emm 12 strains. More kinds of SAg genes profiles were isolated form GAS but with no significant differences seen in the main SAg genes profiles, during the epidemic period.
Antigens, Bacterial/genetics* ; Bacterial Outer Membrane Proteins ; Bacterial Proteins ; Beijing/epidemiology* ; China/epidemiology* ; Exotoxins ; Female ; Humans ; Membrane Proteins ; Pharyngitis/microbiology* ; Pharynx/microbiology* ; Pregnancy ; Pregnancy Complications, Infectious/microbiology* ; Real-Time Polymerase Chain Reaction ; Scarlet Fever/microbiology* ; Streptococcal Infections ; Streptococcus pyogenes/isolation & purification* ; Superantigens/genetics*

Objective: To analyze the genetic characterization of norovirus isolated in an outbreak of gastroenteritis in Jiangsu province. Methods: Extracted viral RNA from the swab samples of cases of acute gastroenteritis outbreak in Jiangsu province on December 16-27, 2016 was reversely transcribed to cDNA, and partial RNA-dependent RNA polymerase sequence and complete capsid sequence (VP1) were amplified by RT-PCR. Amplification products were sequenced for the analysis of genetic characteristics. Results: Based on sequence alignment, the variant shared a high level of identity with the strain GⅡ.g isolated in Spain and Finland (98.7%) in the RNA-dependent RNA polymerase region, and with the strain GⅡ.1 isolated in American (99.4%) in the VP1. The recombination was determined by using software Simplot, and the breakpoint of recombination was located in the ORF1/2 overlap region at position 5 106 of VP1. The result of amino acids alignment in capsid region showed that there were no mutations in the amino acids of the predicted epitopes and receptor binding site Ⅰ-Ⅲ, but a unique amino acid change was detected at position 132 (N-S). Conclusion: The norovirus isolated in the outbreak of gastroenteritis in Jiangsu province was a rare recombinant norovirus variant GⅡ.g-GⅡ.1.
Caliciviridae Infections/epidemiology* ; Capsid Proteins ; Disease Outbreaks ; Gastroenteritis/epidemiology* ; Genotype ; Humans ; Norovirus/isolation & purification* ; Phylogeny ; RNA, Viral/genetics* ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA

Objective: To evaluate the frailty status and understand the relationship between the incidence of fall and frailty status in the elderly in Beijing. Methods: A cross-sectional study was conducted in old people aged ≥60 years in Longtan community of Dongcheng district in Beijing from November 2015 to January 2016. The information about any fall during the past year and frailty status of the elderly were collected with a standardized structured questionnaire in face-to-face interviews. The frailty status of elderly people was assessed with frailty index (FI) method. Logistic regression analysis was used to explore the relationship between fall and frailty status among the elderly. Results: Among 1 557 old people surveyed, the incidence of fall was 17.8% (277/1 557) during the past year. The incidence of fall in women (21.0%, 192/277) was statistically higher than that in men (13.3%, 85/277) (χ(2)=15.288, P=0.000). The median (quartile) value of FI of the elderly surveyed was 0.09 (0.08); and women had a higher FI median value than men [0.10 (0.08) versus 0.08 (0.07)](Z=5.376, P=0.000). The median FI value (quartile range) of 277 old people with history of fall in previous year was 0.12 (0.11), which was higher than the median FI value of 0.08 (0.07) of 1 280 old people without fall history (Z=7.501, P=0.000). Logistic regression analysis showed that higher FI value was associated with more risks for fall; and FI value showed the greatest impact on the incidence and frequency of fall (OR=1.093, 2.234) compared with other related factors of fall, such as age and gender. Conclusion: Frailty status has a greater impact on both incidence and frequency of fall compared with other factors in elderly people in Beijing; more attention should be paid to weak and old adults in the prevention of fall.
Accidental Falls/statistics & numerical data* ; Adult ; Aged ; Beijing ; Cross-Sectional Studies ; Female ; Frail Elderly ; Frailty ; Geriatric Assessment ; Humans ; Incidence ; Male ; Urban Population

Objective: To estimate the prevalence of HIV/HCV co-infection and explore the influence factors and their interaction on HIV/HCV co-infection of patient's access to methadone maintenance treatment (MMT). Methods: A face to face interviews were conducted among 750 patients at two MMT clinics in Guangxi Zhuang Autonomous Region. The questionnaires information included demographic characteristics, HIV and HCV infection status, history of drug abuse, urine test for morphine, high risk sex behaviors, needle sharing, dropped out etc. Methods of χ(2) test one-way, multivariate logistic regression and interactions were used to analyze the related factors of HIV/HCV co-infection. Results: The study subjects included 750 participants, 18.31% (127/691) of patients were co-infected with HIV and HCV. The HIV/HCV co-infection rate in patients who shared needles with others or dropped out of treatment was 35.84% (81/226) and 19.88% (64/322) respectively, which were higher than those who have never shared needles or dropped out (9.89%, 46/465 and 17.07%, 63/369). Logistic regression analysis results showed that after adjusted for confounding factors, patients who shared needles (OR=4.50, 95%CI: 2.72-7.43) and dropped out of treatment (OR=1.71, 95%CI: 1.04-2.80) were more likely to be infected with HIV/HCV. Interaction analysis showed that sharing needles and dropping out of treatment exist additive effect on co-infection of HIV and HCV (RERI=4.21, AP=0.44, SI=1.95). Conclusions: Needle sharing and dropping out of treatment are associated with HIV/HCV co-infection. Health education, psychological counseling and other measures should be taken to reduce needle sharing and dropping out of MMT.
China/epidemiology* ; Coinfection/epidemiology* ; Female ; HIV Infections/epidemiology* ; Hepatitis C/diagnosis* ; Humans ; Logistic Models ; Male ; Methadone/therapeutic use* ; Morphine ; Needle Sharing ; Opiate Substitution Treatment ; Prevalence ; Risk Factors ; Sexual Behavior ; Substance Abuse, Intravenous/drug therapy* ; Substance-Related Disorders

OBJECTIVES: To establish multiplex system of 16 miniSTR loci, and explore its application value for the degraded materials in forensic medicine. METHODS: The multiplex system of 16 miniSTR loci was established using a six-dye fluorescence labeling technology and its application value in forensic medicine was assessed. RESULTS: A six-dye fluorescence labeling miniSTR amplification kit was developed, which enabled 15 autosomal STR loci, Amelogenin locus and DYS391 to be typed simultaneously. This method showed good specificity and could provide stable and accurate typing results with a sensitivity of 50 pg. This system also provided a good test result for the normal biological sample of actual cases. CONCLUSIONS The multiplex system of 16 miniSTR loci has application value for degraded and trace materials with the advantages of high sensitivity and database compatibility, which can be used for forensic casework.
Amelogenin ; DNA Fingerprinting ; DNA Primers ; Forensic Medicine/methods* ; Microsatellite Repeats/genetics* ; Polymerase Chain Reaction

Objective: To identify related factors associated with unprotected anal intercourse (UAI) among HIV-positive men who have sex with men (MSM) in the context of knowing their HIV infection status. Methods: HIV positive MSM who known that they had been infected with HIV for more than 6 months and accepted follow up services were recruited by convenience sampling method in Chengdu 2015. Semi-structured questionnaire was used to collect their information, such as demographic characteristics, antiviral therapy and sexual behavior characteristics etc. Logistic regression model was used for univariate and multivariate analyses. Results: A total of 330 HIV- positive MSM were recruited, 201 eligible MSM were interviewed. The prevalence of UAI in recent six months was 18.41% (37/201). The results of multivariate logistic regression analysis revealed that the number of anal intercourse with male ≥3 in last month (OR=6.22, 95%CI: 1.88-20.56), low education level (OR=7.29, 95%CI: 1.36-39.16), married, divorced or widowed status (OR=4.65, 95%CI: 1.13-19.17), homosexual cohabitation (OR=3.32, 95%CI: 1.01-10.95) were the risk factors related with UAI among the HIV-positive MSM. Conclusion: Frequent homosexual anal intercourse, low education level, married, divorced or widowed status and homosexual cohabitation might be the risk factors related with UAI in HIV-positive MSM in Chengdu.
HIV ; HIV Infections/transmission* ; Homosexuality, Male ; Humans ; Male ; Risk-Taking ; Sexual Behavior ; Sexual Partners ; Sexual and Gender Minorities ; Unsafe Sex

Objective: To understand the genotype of the Yersinia (Y.) pestis strains isolated from Heqing county, Yunnan province in 2017 and provide evidence for the prevention and control of plague in this area. Methods: Ten Y. pestis strains isolated from Heqing were typed by the detections of different region (DFR) and clustered regularly interspaced short palindromic repeats (CRISPRs) as well as multiple-locus variable-number tandem repeat analysis (MLVA). And the results were compared with those of the 93 Y. pestis strains from the adjacent plague foci of Heqing obtained from the established database for clustering analysis. Results: The results showed that Heqing strains had the same type of DFR (Genomovar 05) and CRISPRs (Cluster Ca7, Type 22) with isolates from the plague focus in Lijiang. Heqing strains and Lijiang strains were in the same cluster in MST and only VNTR loci N2117 and M23 of Heqing strains were different from that of Lijiang strains. Conclusion: The Y. pestis strains isolated from Heqing in 2017 were highly homogenous with the strains isolated from wild rodents in plague focus in Lijiang, and Heqing plague might be the result of further southward spread of Lijiang plague.
Animals ; China/epidemiology* ; Epidemiological Monitoring ; Genotype ; Minisatellite Repeats ; Molecular Typing ; Plague/microbiology* ; Rodentia/microbiology* ; Yersinia pestis/pathogenicity*

Objective: To investigate the association between alcohol consumption and lung cancer risk in Chinese males. Methods: Information on alcohol consumption and outcomes were collected on a biennial basis among males in Kailuan Cohort (2006-2015). In addition, electronic databases of hospitals affiliated to Kailuan Community, Insurance Systems of Kailuan Community and Tangshan were also used for supplementary information retrieval. Cox proportional hazards regression models were used to evaluate the hazard ratio (HR) and 95%CI of baseline frequency and type of alcohol consumption associated with lung cancer risk in males. Non-drinkers were used as control group. Results: A total of 101 751 males were included and 913 new lung cancer cases were identified in the Kailuan male cohort study, with a total follow-up time of 808 146.56 person-years and a median follow-up time of 8.88 years by 31 December 2015. After adjusting for potential confounding factors, the HR of former drinkers, occasional drinkers (<1/day) and drinkers (≥1/day) were 1.30 (95%CI: 0.90-1.88), 0.80 (95%CI: 0.64-1.01) and 1.04 (95%CI: 0.85-1.27), respectively, compared with non-drinkers. In addition, drinking beer/red wine (HR=0.91, 95%CI: 0.69-1.20) and white wine (HR=0.99, 95%CI: 0.83-1.19) showed no significant association with lung cancer. The results were similar when stratified analysis were conducted. Conclusion: Our study results don't support the hypothesis that alcohol consumption is significantly associated with the risk of lung cancer in males.
Adult ; Alcohol Drinking/epidemiology* ; China/epidemiology* ; Cohort Studies ; Humans ; Lung Neoplasms/epidemiology* ; Male ; Middle Aged ; Proportional Hazards Models ; Prospective Studies ; Risk Factors

Objective: To assess the association and intensity of baseline TC level with the incidence of lung cancer in men in China. Methods: Since May 2006, all the male workers, including the employees and the retirees in Kailuan Group were recruited in the Kailuan male dynamic cohort study. Information about demographics, medical history, anthropometry and TC level were collected at the baseline interview, as well as the information of newly-diagnosed lung cancer cases during the follow-up period. According to guidelines for blood lipids in Chinese adults and the distribution in the population, TC level was classified into five groups as followed: <160, 160-, 180-, 200- and ≥240 mg/dl, with the second quintile group (160- mg/dl) serving as the referent category. Cox proportional hazards regression model and restricted cubic spline (RCS) model were used to evaluate the association and the nonlinear association between baseline TC level and the risk of lung cancer in the men. Results: By December 31, 2014, for the 109 884 men, a follow up of 763 819.25 person-years was made with a median follow-up period of 7.88 years. During the follow up, 808 lung cancer cases were identified. After adjustment for age, education level, income level, smoking status, alcohol consumption level, history of dust exposure, FPG level and BMI, HR (95%CI) of lung cancer for men with lower TC level (<160 mg/dl) and higher TC level (≥240 mg/dl) were 1.34 (1.04- 1.72) and 1.45 (1.09-1.92), respectively, compared with men with normal TC level (160- mg/dl). The results didn't change significantly after exclusion of newly diagnosed cancer cases within 2 years of follow up and subjects with the history of hyperlipidemia. Conclusion: Our results showed that TC might be associated with higher risk of lung cancer. Men with lower TC level or higher TC level had higher risk for lung cancer. Keep moderate TC level might be one of the effective precaution for the prevention of lung cancer.
Adult ; Asian People ; China/epidemiology* ; Cholesterol/blood* ; Cohort Studies ; Humans ; Incidence ; Lipids ; Lung Neoplasms/ethnology* ; Male ; Proportional Hazards Models ; Prospective Studies ; Risk Factors