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Monitoring signals for vaccine safety: the assessment of individual adverse event reports by an expert advisory committee. Advisory Committee on Causality Assessment.

Monitoring vaccine safety is a complex and shared responsibility. It can be carried out in many ways, one of which is the reporting of individual cases of adverse reactions thought to be due to vaccination. The task is difficult because ascribing causality to an individual case report is fraught with challenges. A standardized evaluation instrument--known as the causality assessment form--was therefore developed for use by an expert advisory committee to facilitate the process. By following the several sections in this form, the members of the committee are taken through a series of points to establish causality. These points include the basic criteria for causation such as biological plausibility, the time elapsed between the vaccine administration and the onset of the adverse event, and whether other factors (drugs, chemicals or underlying disease) could account for the adverse symptoms. The form concludes with a consensus assessment of causality, a commentary about the assessment, and advice for further study or follow-up. This method of assessing the more serious cases of adverse reaction reported to vaccination has proven useful in evaluating ongoing safety of vaccines in Canada. Through analyses such as this, new signals can be identified and investigated further.

Adverse Drug Reaction Reporting Systems↗

Schedules of reinforcement as determinants of human causality judgments and response rates.

Experiments examined the effect of relationships between a response and an outcome on human judgments of causal effectiveness. In Experiment 1, the time between outcomes obtained on a variable ratio (VR) schedule became the intervals for a yoked variable interval (VI) schedule. Response rates were higher on the VR than on the VI schedule. In Experiment 2, the number of responses required per outcome on a VR schedule were matched to that on a master VI 20-s schedule. Both ratings of causal effectiveness and response rates were higher in the VR schedule. In Experiment 3, tandem VI fixed-ratio (FR) schedules produced higher rates and judgments than equivalent conjunctive VI FR schedule. In Experiment 4, a VI schedule with a reinforcement requirement for a short interresponse time (IRT) produced higher rates and judgments than a simple VI schedule. These results corroborate the view that schedules are a determinant of both response rates and causal judgments. Few current theories of causal judgment predict this pattern of results.

Adolescent↗

Discovery of gene-regulation pathways using local causal search.

This paper reports the methods and results of a computer-based algorithm that takes as input the expression levels of a set of genes as given by DNA microarray data, and then searches for causal pathways that represent how the genes regulate each other. The algorithm uses local heuristic search and a Bayesian scoring metric. We applied the algorithm to induce causal networks from a mixture of observational and experimental gene-expression data on genes involved in galactose metabolism in the yeast Saccharomyces cerevisiae. The observational data consisted of gene-expression levels obtained from unmanipulated inverted exclamation mark degrees wild-type inverted exclamation mark +/- cells. The experimental data were produced by deleting ( inverted exclamation mark degrees knocking out inverted exclamation mark +/-) genes and measuring the expression levels of other genes. We used this data to evaluate several variations of the local search method. In each evaluation, causal relationships were predicted for all 36 pairwise combinations of nine key galactose-related genes. These predictions were then compared to the known causal relationships among these genes.

Algorithms↗

Causal beliefs and conditioned responses: retrospective revaluation induced by experience and by instruction.

The author tested causal beliefs and conditioned responses in a task involving retrospective revaluation of the causal status of a target cue with respect to electric shock. Successful revaluation was observed on both self-report shock expectancy and skin conductance, whether the training trials were directly experienced, described, or partly experienced and partly described. The results contradict models that link anticipatory conditioned responses to a separate or earlier process from that underlying explicit causal knowledge. They suggest instead that a single learning process gives rise to propositional knowledge that (a) drives anticipatory responding, (b) forms the basis for self-reported causal beliefs, and (c) can be combined with other knowledge, provided either by experience or symbolically, to generate inferences such as retrospective revaluation.

Association Learning↗

Causal models of leukaemia and lymphoma.

In this chapter, we apply the molecular epidemiological paradigm of biomarkers of exposure, early effect and susceptibility to causal models of leukaemia and lymphoma. The aim is to enhance the development of biomarkers for use in studying the causes of these haematopoeitic cancers in the general population. Two causal models of acute myeloid leukaemia are discussed in detail: chemotherapy-induced and benzene-induced acute myeloid leukaemia. Specific chromosomal changes found in acute myeloid leukaemia may serve as useful biomarkers of early effect in these models, and genetic variants in glutathione S-transferases, NQO1 and DNA-repair enzymes may serve as useful biomarkers of susceptibility. Several causal models of lymphoma exist in which biomarkers could be developed and validated. These include human immunodeficiency virus (HIV) immunosuppression, families with inherited disorders and workers exposed to petroleum products, pesticides or organochlorines. Biomarkers of early effect could include markers of DNA double-strand breaks and aberrant V(D)J recombination, and susceptibility may be related to polymorphisms in genes controlling DNA repair and immunological status. We predict that biomarkers of susceptibility will continue to be studied in the case-control format, perhaps in large pooled studies, but that for biomarkers of early effect, there will be a move away from the study of diseased populations to the study of individuals 'at risk' in the causal models described above.

Autoimmunity↗

Causal relationship between cannabis use and psychotic symptoms or depression. Should we wait and see? A public health perspective.

The aim of this paper is to update and critically analyze the public health relevance of available evidence about the causal relationship between cannabis use and psychosis or depression. There are conflicting views about this causal relationship. Two systematic reviews of existing evidence assessed this association and were published in 2004, but they came to different conclusions. From a public health perspective a thorough discussion is warranted before attributing any observed effect to potential biases. First, the impact of residual confounding in this causal relationship is discussed. We consider that the attenuation of estimates after controlling for confounding factors cannot be interpreted as evidence to support the claim that residual confounding fully explains this link. Secondly, taking into account the results of recent studies, the time-sequence and dose-response criteria of causality are discussed. The fact that unreported or subclinical psychological problems might have preceded and precipitated cannabis use is a very unlikely explanation when the cannabis-psychosis outcome link is assessed from different longitudinal studies. And finally, available evidence is interpreted with a broad view of public health and by taking into account the precautionary principle. We therefore provide reasons to support the case that stronger preventive actions against cannabis are still required in order to avoid the potential increased incidence of psychosocial health problems in the future.

Depression↗

Early differentiation of causal mechanisms appropriate to biological and nonbiological kinds.

Although Piaget characterized young children as precausal until about 7-8 years of age, recent work indicates that preschoolers do honor fundamental principles of causality. This literature has mainly focused on general principles invoked in reasoning about mechanical events. By contrast, the present study examined whether children differentiate between the causal mechanisms appropriate for different conceptual domains. The results of 3 preliminary investigations and 1 main experiment suggested that preschoolers prefer natural mechanisms for color inheritance in biological kinds, particularly when causal substrates resemble their consequences. By contrast, the same children recognized the importance of human intentions in producing the color of an artifact, and also judged that mechanical mechanisms serve to mediate between intentions and outcomes. The results are relevant to recent studies on the development of biological thought, and overall suggest that early causal reasoning reflects both domain-specific and domain-general principles.

Child↗

[Representation of relations between television watching and delinquency within the scope of causal analysis models].

The subject of research coucerns causal relationships between variables of consuming home videos and television and different indicators of delinquency ("acceptance of social norms" (NORM-AK), "perceived risk of punishment" (DEL-RISK), "severity of negative consequences" (NEG-VAL), "acceptance of illegitimate means" (ILLEG-M)). Additionally, factors of influence external to media are taken into consideration which are connected with delinquency according to criminologic results, i.e. variables of communication and variables of the family life and the structure of the family. The model is tested by a sample of N = 305 male pupils of a Regensburg vocational school with methods analysing causality ("2-Stage-Least-Square" (2-SLS) and "Latent variables path analysis with partial least squares estimation" (LVPLS)). The 2-SLS-estimates largely confirm the causal relationships supposed in the model. The results are, three significantly positive indirect connections from the preference for violence of home videos to the main indicator of delinquency ILLEG-M (by way of the variables "consumption of home videos" put on the Index, NEG-VAL and DEL-RISK). The direct influence of the preference for violence on television on ILLEG-M is confirmed, whereas the direct path from the popularity of violent video films to ILLEG-M cannot be proved. The LVPLS-results essentially correspond to the relationship shown by 2-SLS; in addition the LVPLS-estimates also confirm direct causal relationships between the latent variables "consumption of violent video films" and "delinquency proneness".

Adolescent↗

Spontaneous causal searching and adjustment to abnormal Papanicolaou test results.

A search for the cause of unexpected negative events has been proposed to occur commonly and to promote adjustment. The purpose of this descriptive study was to determine the frequency of spontaneous causal searching about abnormal Papanicolaou test (Pap) results and the relationship between searching and adjustment to these results. Participants (N = 118) had abnormal Pap results indicating a need for follow-up with colposcopy. The questions asked on hearing these results were coded for content reflecting spontaneous causal searching. Measures of adjustment (type of expectations about follow-up, negative emotions, and prompt attendance) were obtained at follow-up. Only 34% of participants spontaneously asked causal questions. Causal searching was not associated with expectations, emotions, or attendance.

Adaptation, Psychological↗

Causal reasoning and inference making in judging the importance of story statements.

The present study investigated the development of the ability to judge the importance of story statements on the basis of their causal properties. Key statements were varied with respect to 2 factors: in terms of the number of their causal relations, and in terms of the kinds of relations they had. Relations were either intraepisodic, that is, connecting statements in the same episode, or interepisodic, that is, connecting statements in different episodes. Children 8, 11, 14, and 18 years of age judged the importance of the statements. Children in all 4 age groups judged statements with many intraepisodic causal relations as more important than statements with few such relations. Only children 11 years and older judged statements as more important when they had interepisodic relations than when they did not. Thus, although young children may be sensitive to quantitative aspects of a statement's relational role within an episode, they may not be as aware of qualitative, that is, structural, differences between kinds of relations. Answers to why questions confirmed these patterns. Older children more often gave answers that crossed episodic boundaries than did the younger children. These findings may reflect age-related differences in children's ability to infer relations between statements and to integrate the information contained in stories. They also attest to the central role that causal inferences play in the interpretation of what is important information in stories.

Adolescent↗

Simulated grading decisions of allied health educators. Part II: Variations in causal attributions.

The present study investigated the causal attributions of allied health faculty to hypothetical student achievement data. Faculty rated linear and nonlinear (ascending or descending) grade profiles along ten causal dimensions. As predicted, student ability and effort attributions were prominent for ascending and uniformly high performance while external factors were more prevalent for descending and uniformly low performance. Faculty also used a diverse set of attributions in rating the performance profiles. Faculty age and length of clinical experience appeared to have mediating effects on perceptions of causality for declining student performance. Overall, these results suggest that allied health faculty demonstrate predictable patterns of causal attributions, yet differ in several important aspects from that expected from previous research.

Achievement↗

[Causality in psychiatry].

In a brief epistemological and historical review the problem of the attribution of the causal connections as one example of the construction of coherence in 'reality' is discussed. To construe causal connections is but one of our mental activities to relate events or objects, competing with other non-causal determinations: sequential, functional, teleological, statistical, dialectic. The attribution of causal connections is a valuable, but always approximative heuristic means of scientific exploration. The concurring etio-pathogenetic concepts of schizophrenias and borderline-disorders are dealt with to exemplify the actual problems in psychiatric research.

Brain↗

Summarization of complex causal diagnostic hypotheses.

The Heart Disease Program produces detailed causal diagnostic hypotheses for patients with cardiovascular diseases. This poster discusses our experience with summarizing these hypotheses for the physician. The basic approach is to merge the nodes of the structure indicating causal mechanism into the more important nodes. Analysis of the results shows that to generate effective summaries the identification of syndromes is very important, the definitions of the labels need to be carefully enforced, the causality of diseases should be supported by evidence and not just probability, and the sense of causal order must be carefully preserved.

Heart Diseases↗

Development in children's causal theories of their seizure disorders.

Despite the prevalence of seizure disorders in children, little is known about how youngsters with epilepsy understand the cause of their disorder. Fifty children and adolescents with idiopathic seizure disorders, between 5- and 16-years-old, were questioned about the etiology of seizure episodes and of seizure disorders, as well as their understanding of physical causality, general illness causality, and brain functioning. Responses were scored for their conceptual complexity according to scales paralleling Piaget's stages of cognitive development. Older children had more cognitively sophisticated concepts of epilepsy than did younger children. Overall, however, children scored significantly lower on questions about their seizure disorders than on questions assessing their understanding of physical causality, general illness causality, and brain functioning. Many children had misconceptions about seizure disorders and lacked disease-related information; only 41% of the children identified epilepsy as a disease involving the brain. These findings underline the need for including educational intervention in the comprehensive care of pediatric seizure disorders.

Adolescent↗

[Assessment of causal relationship in work-related pulmonary diseases. An epidemiological approach].

A competent assessment of causal relationships in the case of work-related lung disorders depends on correct diagnosis, a detailed occupational history and updated epidemiological knowledge about causal relationships, obtained from the literature. Assessments for purposes of compensation demand, in addition, an explicit choice of methods for calculating causes, before a meaningful attempt can be made to weight the various factors in and outside the working environment. If adequate epidemiological knowledge is available, the causal probability, based on the etiological fraction among the exposed persons (attributable risk) may be a useful tool for apportioning the different causal factors.

Disability Evaluation↗

[Causal assessment of drug-induced acute colitis. A prospective study of 58 consecutive cases].

AIMS: The causal effect of drugs is underestimated in patients with inflammatory bowel disease. The aim of this study was to assess the causal implication of drugs in acute colitis. METHODS: A prospective study was conducted in 58 consecutive patients with an acute inflammation of the colonic mucosa. Recent drug intake was recorded and possible causal effects were analyzed exhaustively with respect to both intrinsic and bibliographic criteria. RESULTS: Causal assessment scores were high for 57 drugs and 41 patients. Drug-induced acute colitis was diagnosed in 35 cases. In 7 patients, physician practice had not taken into account drug use despite probable drug involvement. The main drugs implicated were antibiotics (n = 42) and non steroidal anti-inflammatory drugs (n = 10). CONCLUSION: Acute colitis is mainly induced by drugs.

Acute Disease↗

Causal estimation of time-varying treatment effects in observational studies: application to depressive disorder.

Clinicians recognize three phases of the treatment of major depression: an acute phase to control disabling symptoms, a continuation phase to avoid relapses of a single episode, and a preventive phase to avoid recurrences of new episodes over time. With no directly measurable trace of the underlying pathological process, the distinction is based arbitrarily on the passage of time in remission. The clinician who has successfully treated a patient with antidepressant medications in the acute phase has a critical clinical decision to make for the continuation and preventive phases: whether to continue to prescribe the medication, for how long, and at what dose. This decision, like most clinical decisions in psychiatry, is not yet completely determined by the results of randomized clinical trials. Only a handful of such trials have been completed, covering just a fraction of the possible maintenance strategies (defined by treatment drop times). For many reasons, observational studies of the outcome of naturally occurring treatment choices play an important supporting role, helping to extend the reach of completed studies and to design new studies. Causal inference from observational studies has usually been considered in the context of a decision among a few fixed alternatives at a single time. The particular causal effect of interest in the maintenance of remission dictates that treatment be studied over remission time. This challenges the causal analysis of the observational study. We present issues arising from assessing temporal treatment effects due to nonrandomized treatment assignment over time. We use data from a large observational study of the course of affective illness, to illustrate an approach to this problem.

Bias↗

Unraveling causal links between chronic rhinosinusitis and peripheral artery diseases: insights from genetic correlations through genome-wide association studies.

OBJECTIVES: Chronic Rhinosinusitis (CRS) shares epidemiological links with Cardiovascular Diseases (CVDs), however, their shared genetic basis remains unclear. We hypothesized that pleiotropic genetic variants underlie CRS-CVDs links via distinct biological pathways. METHODS: Using large-scale GWAS data from European-ancestry individuals, we assessed global and local genetic correlations. We applied Genomic Structural Equation Modeling (Genomic SEM) to dissect shared genetic architecture, performed bidirectional Mendelian Randomization (MR) to infer causality, and conducted cis-eQTL colocalization to identify shared genetic signals. Finally, in vitro endothelial models (HUVECs) validated the functional dynamics of candidate genes under CRS-mimicking inflammatory stress. RESULTS: CRS showed significant genetic correlations with multiple CVDs. Genomic SEM revealed a latent factor structuring shared genetic risk through three pathways: artery diseases, myocardial diseases, and heart failure. Local genetic correlations identified significant local genetic correlations specifically between CRS and Peripheral Atherosclerosis (PAS)/Peripheral Artery Disease (PAD) specifically within the chr6: 31.57&#x2012;33.24 Mb locus. MR demonstrated causal effects of CRS on PAD (OR&#x2009;=&#x2009;1.23, p&#x2009;=&#x2009;0.022) and PAS (OR&#x2009;=&#x2009;1.21, p&#x2009;=&#x2009;0.011), but not vice versa. Genetically predicted HLA-DRB1, APOM, and COL11A2 expression conferred protection, while HLA-DQA2 increased risk. Crucially, in vitro validation corroborated these pathogenic trajectories, inflammatory stress significantly downregulated the protective APOM and upregulated the risk-associated HLA-DQA2 alongside pro-atherogenic VCAM-1, while HLA-DRB1 exhibited a compensatory upregulation (p&#x2009;<&#x2009;0.05). CONCLUSION: CRS shares global genetic liability with CVDs, structured through three primary etiological pathways. Causal effects of CRS on peripheral artery diseases are mediated by immune and lipid-related genes within the chr6 locus, revealing divergent pleiotropic mechanisms. Our integrated genetic and in vitro evidence provides a mechanistic framework wherein chronic mucosal inflammation contributes to systemic endothelial vulnerability, thereby highlighting candidate targets for mechanism-directed therapy.

Humans↗