Introduction on 'assessing the risk of bias of individual studies' in systematic review of health-care intervention programs revised by the Agency for Healthcare Research and Quality / 中华流行病学杂志

This paper summarizes the Risk of Bias of Individual Studies in Systematic Reviews of Health Care Interventions revised by the Agency for Healthcare Research and Quality (AHRQ) and introduces how to use Revman software make risk of bias graph or risk of bias summary. AHRQ tool can be used to evaluate following study designs: RCTs, cohort study, case-control study (including nested case-control), case series study and cross-sectional study. The tool evaluates the risk of bias of individual studies from selection bias, performance bias, attrition bias, detection bias and reporting bias. Each of the bias domains contains different items, and each item is available for the assessment of one or more study designs. It is worth noting that the appropriate items should be selected for evaluation different study designs instead of using all items to directly assess the risk of bias. AHRQ tool can be used to evaluate risk of bias individual studies when systematic reviews of health care interventions is including different study designs. Moreover, the tool items are relatively easy to understand and the assessment process is not complicated. AHRQ recommends the use of high, medium and low risk classification methods to assess the overall risk of bias of individual studies. However, AHRQ gives no recommendations on how to determine the overall bias grade. It is expected that future research will give corresponding recommendations.

Series of risk of bias assessment (5): Risk Of Bias In Non-randomized Studies-of Interventions (ROBINS-I) / 中华流行病学杂志

This paper summaries the Risk Of Bias In Non-randomized Studies-of Interventions (ROBINS-I), a tool for evaluating risk of bias about Non-randomized Studies-of Interventions (NRSI), and introduces the application of ROBINS-I in a published NRSI. According to the characteristics of NRSI, evaluation field and signaling question were designed in ROBINS-I to provide essential information about risk of bias for NRSI included in systematic reviews. ROBINS-I is the tool in assessment of risk of bias in observational studies and quasi-randomised studies. Although the tool has been used in practice to some extent, but it still needs further improvement. Attention should be paid to its update and progress.

Risk on bias assessment: (6) A Revised Tool for the Quality Assessment on Diagnostic Accuracy Studies (QUADAS-2) / 中华流行病学杂志

This paper introduced the Revised Tool for the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2), including the development and comparison with the original QUADAS, and illustrated the application of QUADAS-2 in a published paper related to the study on diagnostic accuracy which was included in systematic review and Meta-analysis. QUADAS-2 presented considerable improvement over the original tool. Confused items that included in QUADAS had disappeared and the quality assessment of the original study replaced by the rating of risk on bias and applicability. This was implemented through the description on the four main domains with minimal overlapping and answering the signal questions in each domain. The risk of bias and applicability with 'high','low' or 'unclear' was in line with the risk of bias assessment of intervention studies in Cochrane, so to replace the total score of quality assessment in QUADAS. Meanwhile, QUADAS-2 was also applicable to assess the diagnostic accuracy studies in which follow-up without prognosis was involved in golden standard. It was useful to assess the overall methodological quality of the study despite more time consuming than the original QUADAS. However, QUADAS-2 needs to be modified to apply in comparative studies on diagnostic accuracy and we hope the users would follow the updates and give their feedbacks on line.

Risk of bias assessment: (7) Assessing Bias in Studies of Prognostic Factors / 中华流行病学杂志

This paper introduces the tools related to Quality In Prognosis Studies (QUIPS) to assess the risk of bias in studies of prognostic factors and the relevant points of assessment and to illustrate the application of QUIPS in published prognostic research. The QUIPS tool identified 6 important areas to consider when evaluating validity and bias in studies of prognostic factors including participation, attrition, measurement on prognostic factors, outcomes, confounding factors, statistical analysis and reporting. It also provided a new method for evaluation on bias in the areas of prognostic research.

Characteristics on spatial and temporal distribution as well as the driving effect of meteorological factors on brucellosis in Datong city, Shanxi province, 2005-2015 / 中华流行病学杂志

Objective: To explore the spatio-temporal epidemic trends and related driving effects of meteorological factors on brucellosis in Datong city, Shanxi province, from 2005 to 2015. Methods: We collected the surveillance data on brucellosis and related meteorological data in Datong city from 2005 to 2015, to describe the epidemic characteristics of the disease. Quasi-Poisson distribution lag non-liner model (DLNM) was built to explore the driving effect of monthly meteorological data on the disease. Results: From 2005 to 2015, Datong city reported a total of 17 311 cases of brucellosis including one death, with the annual average incidence as 47.43 per 100 000 persons. A rising trend was seen during the study period. The monthly incidence of Brucellosis presented an obvious curve with a major peak from March to June, accounted for 48.40% of the total cases. The high incidence areas in the city gradually expanded from the northeast and southeast to the western areas. Results from the DLNM studies suggested that seasonality of brucellosis in Datong was significantly affected by metrological factors such as evaporation, rainfall and temperature. The peak of delayed effect appeared the highest when the monthly cumulative evaporation capacity was 140-260 mm and the monthly cumulative rainfall was 20-60 mm with lag less than 1 month or the monthly temperature was -13 ℃ with lag of 4-5 months. Conclusions: The incidence of human brucellosis in Datong city increased significantly from 2005 to 2015. Meteorological factors such as evaporation, rainfall, temperature all showed significant driving effects on the disease.

Interactive effects between health literacy and mobile phone dependence as well as its relation with unintentional injuries in middle school students / 中华流行病学杂志

Objective: To investigate the interaction between health literacy, mobile phone dependence and unintentional injuries in middle school students, and to provide guidance for prevention on unintentional injuries in adolescents. Methods: From November 2015 to January 2016, a questionnaire survey was conducted among 22 628 middle school students in Shenyang of Liaoning province, Bengbu of Anhui province, Xinxiang of Henan province, Ulanqab of Inner Mongolia Autonomous Region, Chongqing and Yangjiang of Guangdong province. Chinese Adolescent Interactive Health Literacy Questionnaire (CAIHLQ), Self-rating Questionnaire for Adolescent Problematic Mobile Phone Use (SQAPMPU), and Unintentional Injuries Assessment Scale and demographic variables were used to measure the health literacy, mobile phone dependence and unintentional injuries among the Chinese middle school students. Results: The detection rates of mobile phone dependence and unintentional injuries were 25.4% and 46.7%, respectively. The rates of unintentional injuries of middle school students with mobile phone dependence and with low, medium and high health literacy were 53.6%, 44.4% and 48.8%, 48.1%, 41.7%. Factors as mobile phone dependence, low and middle health literacy were positively related to unintentional injuries (OR=1.452, 1.196, 1.364). However, the multiplicative interaction between mobile phone dependence and health literacy on unintentional injuries was noticed significant (OR=1.217, 95%CI: 1.041-1.422). Conclusions: Our results showed that the prevalence of unintentional injuries was relatively high in middle school students. Health literacy and mobile phone dependence seemed related to unintentional injuries. Interaction between health literacy and mobile phone dependence on unintentional injuries appeared significant.

Risk of bias assessment: (9) Application of the risk of bias assessment results / 中华流行病学杂志

In this last paper of the series about risk of bias assessment, we introduce the application of risk of bias assessment results. Risk of bias assessment is one of the key steps in the assessment of quality of evidence. The risk of bias assessment results could be the "diagnosis" of individual studies, which helps decision making related to the inclusion and exclusion of individual studies, as well as the data analysis in the systematic review process. This paper focuses on how to incorporate risk of bias assessment results in the GRADE assessment for quality of evidence, including the principles and the tips for the application.

Spinal Cord Ischemia Secondary to Hypovolemic Shock

A 44-year-old male presented with symptoms of spinal cord compression secondary to metastatic prostate cancer. An urgent decompression at the cervical-thoracic region was performed, and there were no complications intraoperatively. Three hours postoperatively, the patient developed acute bilateral lower-limb paralysis (motor grade 0). Clinically, he was in class 3 hypovolemic shock. An urgent magnetic resonance imaging (MRI) was performed, showing no epidural hematoma. He was managed aggressively with medical therapy to improve his spinal cord perfusion. The patient improved significantly, and after one week, he was able to regain most of his motor functions. Although not commonly reported, spinal cord ischemia post-surgery should be recognized early, especially in the presence of hypovolemic shock. MRI should be performed to exclude other potential causes of compression. Spinal cord ischemia needs to be managed aggressively with medical treatment to improve spinal cord perfusion. The prognosis depends on the severity of deficits, and is usually favorable.

Influence of glutathione-S-transferase (GSTM1, GSTP1, GSTT1) and cytochrome p450 (CYP1A1, CYP2D6) polymorphisms on numbers of basal cell carcinomas (BCCs) in families with the naevoid basal cell carcinoma syndrome.

BACKGROUND: The naevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant multisystem disorder with variable expression. NBCCS patients have variable susceptibility to development of basal cell carcinoma (BCC). Previous studies have shown that polymorphisms of some metabolic genes encoding the cytochrome p450 (CYP) and glutathione-S-transferase (GST) enzymes influenced the numbers of BCCs in sporadic BCC cases. OBJECTIVE: To determine whether allelic variants of these genes contribute to the variation in numbers of BCCs observed in NBCCS families. METHODS: Genotyping and analysis was carried out in 152 members (69 affected and 83 unaffected) of 13 families with NBCCS for seven polymorphisms in five metabolic genes including CYP1A1, CYP2D6, GSTM1, GSTP1, and GSTT1. RESULTS: GSTP1 Val105 and GSTP1 Val114 alleles were significantly associated with fewer BCC numbers (odds ratio (OR)105 = 0.55 (95% confidence interval, 0.35 to 0.88); OR114 = 0.20 (0.05 to 0.88)). The Val(105) allele showed a dose dependent effect (OR(Ile/Val) = 0.58 (0.34 to 0.88); OR(Val/Val) = 0.34 (0.14 to 0.78)). In addition, fewer jaw cysts were observed in carriers of the three p450 polymorphisms (CYP1A1m1, CYP1A1m2, and CYP2D6*4) (OR(CYP1A1m1) = 0.27 (0.12 to 0.58); OR(CYP1A1m2) = 0.25 (0.08 to 0.78); OR(CYP2D6*4) = 0.33 (0.18 to 0.60)). CONCLUSIONS: Genetic variants might contribute to the variation in numbers of BCCs and jaw cysts observed in NBCCS families.