A systematic review finds that diagnostic reviews fail to incorporate quality despite available tools

BACKGROUND AND OBJECTIVE: To review existing quality assessment tools for diagnostic accuracy studies and to examine to what extent quality was assessed and incorporated in diagnostic systematic reviews. METHODS: Electronic databases were searched for tools to assess the quality of studies of diagnostic accuracy or guides for conducting, reporting or interpreting such studies. The Database of Abstracts of Reviews of Effects (DARE; 1995-2001) was used to identify systematic reviews of diagnostic studies to examine the practice of quality assessment of primary studies. RESULTS: Ninety-one quality assessment tools were identified. Only two provided details of tool development, and only a small proportion provided any indication of the aspects of quality they aimed to assess. None of the tools had been systematically evaluated. We identified 114 systematic reviews, of which 58 (51%) had performed an explicit quality assessment and were further examined. The majority of reviews used more than one method of incorporating quality. CONCLUSION: Most tools to assess the quality of diagnostic accuracy studies do not start from a well-defined definition of quality. None has been systematically evaluated. The majority of existing systematic reviews fail to take differences in quality into account. Reviewers should consider quality as a possible source of heterogeneity.     

Functional constipation in infants: a follow-up study

Our objective of this study was to describe the clinical course of severe functional constipation in early childhood. Eligible patients were 47 children (60% boys; median age, 3.5 months) who had constipation in their first year of life. Follow-up data were obtained through a standardized questionnaire. Success was defined as a period of at least 4 weeks with > or =3 painless bowel movements per week. Six months after initial evaluation, 69% of the children were recovered. After initial success, a relapse occurred in 15% of the children within 3 years. A duration of symptoms <3 months before referral correlated significantly with better outcome. We conclude that most infants with severe constipation evaluated at a tertiary center are recovered after 6 months. Early therapeutic intervention may beneficially contribute to the resolution of constipation.     

Management of asymptomatic anthracycline-induced cardiac damage after treatment for childhood cancer: a postal survey among Dutch adult and pediatric cardiologists

Asymptomatic anthracycline-induced cardiac damage (A-CD) is a serious problem among young childhood cancer survivors. The aim of this survey was to assess the current treatment policy in these patients in the Netherlands. A questionnaire was sent to all 136 departments of adult or pediatric cardiology in the Netherlands. It was returned by 61% of the departments. Sixty-six percent of the respondents started medical treatment (ie, an ACE inhibitor and/or a beta-blocker) in childhood cancer survivors with asymptomatic A-CD. Fifty-eight percent of the respondents indicated that their treatment decision was based on published findings in the literature, but none of them referred to studies evaluating the treatment of asymptomatic A-CD. A majority of adult and pediatric cardiologists started medical treatment in childhood cancer survivors with asymptomatic A-CD without knowledge of the benefits and risks of treatment in this patient group. Before ACE inhibitors and/or beta-blockers can be recommended as routine practice in childhood cancer survivors with asymptomatic A-CD, randomized controlled trials should be performed. Until then, the authors recommend centralizing the treatment of childhood cancer survivors with asymptomatic A-CD in a specialized center to cluster the available knowledge and experience.     

Smoking in Ontario schools: does policy make a difference?

OBJECTIVE: Studies in other countries have shown that school tobacco control policy has potential to prevent smoking uptake in adolescents. Since no Canadian research has studied this association, we assessed the statistical link between school tobacco policy and smoking status in Ontario elementary and secondary schools. METHODS: We conducted secondary analysis of data collected using the School Smoking Profile, a cross-sectional, self-report questionnaire. School policy variables were formed from five survey items concerning students' perceptions of school tobacco control policy. Smoking status was determined through self-report measures which had been validated by carbon monoxide testing. Logistic regression models used school policy variables to explain smoking status in elementary and secondary schools, controlling for school location, school size, and student's grade level. RESULTS: The smoking policy variables, rules and enforcement, explained smoking status after controlling for other variables. In elementary schools, perceptions of stronger enforcement reduced the odds of being a smoker (OR = 0.39, CI99 = 0.34-0.44). In secondary schools, enforcement lost its protective effect (OR = 1.05, CI99 = 1.00-1.10). In addition, student perceptions that rules were strong were indicative of increased smoking in secondary schools (OR = 1.32, CI99 = 1.27-1.37). DISCUSSION: Strong enforcement of school tobacco control policy appears to be effective in elementary schools but is not as helpful in secondary schools. Secondary school policymakers should consider modifying their sanctions to avoid alienating smokers.     

From gene to disease; risk factors for venous thrombosis: factor V Leiden and prothrombin 20210A

Venous thromboembolic disease is an important clinical entity, in which both acquired and genetic risk factors play a causative role. Genetic factors which increase thrombotic risk consist of rare heterogeneous loss-of-function mutations in coagulation-inhibitory factors, such as antithrombin, protein S and C, and more common, but unique, gain-of-function mutations in coagulation factors V and II, so-called factor V-Leiden and prothrombin 20210A. The genetic defect underlying factor V-Leiden is a guanine (G) to adenine (A) mutation in the factor V gene, causing substitution of arginine at position 506 by glutamine, thereby providing resistance to proteolytic cleavage by activated protein C (APC). In the prothrombin 20210A allele a G to A mutation at nucleotide 20210 in the 3'-untranslated region of the prothrombin gene is associated with increased prothrombin levels. The APC-resistance assay is used to screen for the presence of factor V-Leiden. Both factor V-Leiden and prothrombin 20210A are diagnosed by DNA analysis.     

Leserbrief Zum Beitrag von W. Harth und R. Linse: “Botulinophilie” Der Hautarzt (2001) 52:312–316

Ohne Zusammenfassung     

Re-evaluation of the cold face test in humans

The cold face test has been found to be a simple clinical test to elicit the diving reflex, which assesses function of the sympathetic and parasympathetic nerve systems at the same time. However, there is no consensus about how the test should be performed without confounding the results by eliciting other reflexes, such as the oculocardiac reflex. The object of this study was to compare and standardize methods for performing the cold face test. Reproducibility of results was assessed. Groups of 6 to 11 subjects participated in each protocol. To act as a cold stimulus a bag filled with iced-water and having a wet surface was used. The effects of allowing breathing to continue, of different masses of the bag, and of avoiding ocular pressure by wearing diving goggles were investigated. Blood pressure and heart rate were measured beat to beat using an automatic blood pressure measuring device. The cold stimulus used in this study was too small to elicit the oculocardiac reflex: wearing diving goggles and different masses of the bag had no influence on the response. The prevention of breathing, however, tended to enhance the fall in heart rate during the cold stress. Reproducibility was highest when the subjects were habituated to the intensity of the stimulus. We recommend practising the test method in advance and performing it in a setting where the subject is unable to breathe. Accepted: 13 March 2000     

Oleamide activates peroxisome proliferator-activated receptor gamma (PPARγ) in vitro

Background

Lipid metabolism is altered in subjects with liver steatosis. FAS is a key enzyme in de novo lipogenesis and both FAS gene expression and enzymatic activity are primarily regulated by metabolic signals in the liver. Lipoprotein lipase (LPL), the rate-limiting enzyme for the hydrolysis of core triglycerides, plays a pivotal role in lipid metabolism. This study aims to investigate if circulating levels of FAS and LPL could be clinically associated with liver steatosis.

Methods

In this work, we present data obtained from a subsample of 94 subjects with liver steatosis enrolled by NUTRIEPA study, a nutritional trial in subjects with liver steatosis. Serum levels of FAS protein and LPL activity were evaluated by ELISA test and by a fluorescent method, respectively. The diagnosis and the degree of liver steatosis were based on laboratory and ecographic measurements. Statistical methods included Kruskal-Wallis analysis of variance and Wilcoxon signed-rank test, where appropriate. The ?? ² test has been performed to analyse categorical variables.

Results

The subjects with severe steatosis had significantly higher serum levels of FAS protein and LPL activity compared to subjects with mild and moderate liver steatosis. Moreover, a positive trend in serum levels of FAS expression from lower to higher degree of steatosis was also detected.

Conclusions

We describe a relationship between human liver steatosis and elevated levels of circulating lipogenic enzymes. Increased serum levels of FAS expression and LPL activity could be considered a marker of severe liver steatosis.