Using cancer risk algorithms to improve risk estimates and referral decisions

Background: Cancer risk algorithms were introduced to clinical practice in the last decade, but they remain underused. We investigated whether General Practitioners (GPs) change their referral decisions in response to an unnamed algorithm, if decisions improve, and if changing decisions depends on having information about the algorithm and on whether GPs overestimated or underestimated risk. Methods: 157 UK GPs were presented with 20 vignettes describing patients with possible colorectal cancer symptoms. GPs gave their risk estimates and inclination to refer. They then saw the risk score of an unnamed algorithm and could update their responses. Half of the sample was given information about the algorithm’s derivation, validation, and accuracy. At the end, we measured their algorithm disposition. We analysed the data using multilevel regressions with random intercepts by GP and vignette. Results: We find that, after receiving the algorithm’s estimate, GPs’ inclination to refer changes 26% of the time and their decisions switch entirely 3% of the time. Decisions become more consistent with the NICE 3% referral threshold (OR 1.45 [1.27, 1.65], p < .001). The algorithm’s impact is greatest when GPs have underestimated risk. Information about the algorithm does not have a discernible effect on decisions but it results in a more positive GP disposition towards the algorithm. GPs’ risk estimates become better calibrated over time, i.e., move closer to the algorithm. Conclusions: Cancer risk algorithms have the potential to improve cancer referral decisions. Their use as learning tools to improve risk estimates is promising and should be further investigated

Can hypnotic suggestibility be measured online?

Hypnosis and hypnotic suggestions are gradually gaining popularity within the consciousness community as established tools for the experimental manipulation of illusions of involuntariness, hallucinations and delusions. However, hypnosis is still far from being a widespread instrument; a crucial hindrance to taking it up is the amount of time needed to invest in identifying people high and low in responsiveness to suggestion. In this study, we introduced an online assessment of hypnotic response and estimated the extent to which the scores and psychometric properties of an online screening differ from an offline one. We propose that the online screening of hypnotic response is viable as it reduces the level of responsiveness only by a slight extent. The application of online screening may prompt researchers to run large-scale studies with more heterogeneous samples, which would help researchers to overcome some of the issues underlying the current replication crisis in psychology

Reply to Mac Giolla and Ly (2019):On the reporting of Bayes Factors in Deception Research

Bayes factors help researchers by providing a continuous measure of evidence for one hypothesis (e.g., the null, H0) relative to another (e.g., the alternative, H1). Warmelink, Subramanian, Tkacheva and McLatchie (2019) reported Bayes factors alongside p-values to draw inferences about whether the order of expected versus unexpected questions influenced the amount of details interviewees provided during an interview. Mac Giolla & Ly (2019) provided several recommendations to improve the reporting of Bayesian analyses, and used Warmelink et al (2019) as a concrete example. These included (I) not to over-rely on cut-offs when interpreting Bayes factors; (II) to rely less on Bayes factors, and switch to “nominal support”; and (III) to report the posterior distribution. This paper elaborates on their recommendations and provides two further suggestions for improvement. First, we recommend deception researchers report Robustness Regions to demonstrate the sensitivity of their conclusions. Second, we encourage deception researchers to estimate a priori the sample size likely to be required to produce conclusive results

How do I know what my theory predicts?

To get evidence for or against a theory relative to the null hypothesis, one needs to know what the theory predicts. The amount of evidence can then be quantified by a Bayes factor. Specifying the sizes of the effect one’s theory predicts may not come naturally, but I show some ways of thinking about the problem, some simple heuristics that are often useful when one has little relevant prior information. These heuristics include the room-to-move heuristic (for comparing mean differences), the ratio-of-scales heuristic (for regression slopes), the ratio-of-means heuristic (for regression slopes), the basic-effect heuristic (for analysis of variance effects), and the total-effect heuristic (for mediation analysis)

Strategies that reduce Stroop interference

A remarkable example of reducing Stroop interference is provided by the word blindness post-hypnotic suggestion (a suggestion to see words as meaningless during the Stroop task). This suggestion has been repeatedly demonstrated to halve Stroop interference when it is given to highly hypnotizable people. In order to explore how highly hypnotizable individuals manage to reduce Stroop interference when they respond to the word blindness suggestion, we tested four candidate strategies in two experiments outside of the hypnotic context. A strategy of looking away from the target words and a strategy of visual blurring demonstrated compelling evidence for substantially reducing Stroop interference in both experiments. However, the pattern of results produced by these strategies did not match those of the word blindness suggestion. Crucially, neither looking away nor visual blurring managed to speed up incongruent responses, suggesting that neither of these strategies is the likely underlying mechanism of the word blindness suggestion. Although the current results did not unravel the mystery of the word blindness suggestion, they showed that there are multiple voluntary ways through which participants can dramatically reduce Stroop interference

Can unconscious intentions be more effective than conscious intentions? Test of the role of metacognition in hypnotic response

While several theories assume that responses to hypnotic suggestions can be implemented without executive intentions, the metacognitive class of theories postulate that the behaviors produced by hypnotic suggestions are intended and the accompanying feeling of involuntariness is only a consequence of strategically not being aware of the intention. Cold control theory asserts that the only difference between a hypnotic and non-hypnotic response is this metacognitive one, that is, whether or not one is aware of one's intention to perform the relevant act. To test the theory, we compared the performance of highly suggestible participants in reducing the Stroop interference effect in a post-hypnotic suggestion condition (word blindness: that words will appear as a meaningless foreign script) and in a volitional condition (asking the participants to imagine the words as a meaningless foreign script). We found that participants had equivalent expectations that the posthypnotic suggestion and the volitional request would help control the conflicting information. Further, participants felt they had more control over experiencing the words as meaningless with the request rather than the suggestion; and they experienced the request largely as imagination and the suggestion largely as perception. That is, we set up the interventions we required for the experiment to constitute a test of cold control theory. Both the suggestion and the request reduced Stroop interference. Crucially, there was Bayesian evidence that the reduction in Stroop interference was the same between the suggestion and the volitional request. That is, the results support the claim that responding hypnotically does not grant a person greater first order abilities than they have non-hypnotically, consistent with cold control theory

Efficient Expression of <i style="box-sizing: border-box;">Igf-1</i> from Lentiviral Vectors Protects <i style="box-sizing: border-box;">In Vitro</i> but Does Not Mediate Behavioral Recovery of a Parkinsonian Lesion in Rats

Gene therapy approaches delivering neurotrophic factors have offered promising results in both preclinical and clinical trials of Parkinson's disease (PD). However, failure of glial cell line-derived neurotrophic factor in phase 2 clinical trials has sparked a search for other trophic factors that may retain efficacy in the clinic. Direct protein injections of one such factor, insulin-like growth factor (IGF)-1, in a rodent model of PD has demonstrated impressive protection of dopaminergic neurons against 6-hydroxydopamine (6-OHDA) toxicity. However, protein infusion is associated with surgical risks, pump failure, and significant costs. We therefore used lentiviral vectors to deliver Igf-1, with a particular focus on the novel integration-deficient lentiviral vectors (IDLVs). A neuron-specific promoter, from the human synapsin 1 gene, excellent for gene expression from IDLVs, was additionally used to enhance Igf-1 expression. An investigation of neurotrophic effects on primary rat neuronal cultures demonstrated that neurons transduced with IDLV-Igf-1 vectors had complete protection on withdrawal of exogenous trophic support. Striatal transduction of such vectors into 6-OHDA-lesioned rats, however, provided neither protection of dopaminergic substantia nigra neurons nor improvement of animal behavior

Phenomenological control as cold control

We first review recent work from our laboratory, which construes hypnotizability as an example of a more general trait of capacity for phenomenological control, which people can use to create subjective experiences in many nonhypnotic contexts where those experiences fulfill people’s goals. Second, we review recent work, which construes phenomenological control as a specifically metacognitive process, where intentional cognitive and motor action occurs without awareness of specific intentions (cold control theory). In terms of the reach of phenomenological control, we argue that various laboratory phenomena, namely vicarious pain, mirror-touch synesthesia, and the rubber hand illusion are to an unknown degree a construction of phenomenological control. The argument can of course be extended in principle to other findings. In terms of the reach of cold control, we present a new theory of intentional binding and show how intentional binding can measure the absence of conscious intentions in the hypnotic context. We obtain no evidence that cold control confers abilities beyond the changes in the metacognitive monitoring it postulates, and we explore the negative correlation between mindfulness and cold control viewed as a lack of mindfulness of intentions

Cardioprotection by resveratrol: A human clinical trial in patients with stable coronary artery disease

Abstract. Several beneficial effects of resveratrol (RES), a natural antioxidant present in red wine have already been described. The aim of our study was to investigate if RES had a clinically measurable cardioprotective effect in patients after myocardial infarction. In this double-blind, placebo controlled trial 40 post-infarction Caucasian patients were randomized into two groups. One group received 10 mg RES capsule daily for 3 months. Systolic and diastolic left ventricular function, flow-mediated vasodilation (FMD), several laboratory and hemorheological parameters were measured before and after the treatment. Left ventricular ejection fraction showed an increasing tendency (ns) by RES treatment. However, left ventricular diastolic function was improved significantly (p &lt; 0.01) by RES. A significant improvement in endothelial function measured by FMD was also observed (p &lt; 0.05). Low-density lipoprotein (LDL) level significantly decreased (p &lt; 0.05) in the RES treated group. Red blood cell deformability decreased and platelet aggregation increased significantly in the placebo group (p &lt; 0.05), while resveratrol treatment has prevented these unfavourable changes. Concerning other measured parameters no significant changes were observed neither in placebo nor in RES group. Our results show that resveratrol improved left ventricle diastolic function, endothelial function, lowered LDL-cholesterol level and protected against unfavourable hemorheological changes measured in patients with coronary artery disease (CAD)

A review of applications of the Bayes factor in psychological research

The last 25 years have shown a steady increase in attention for the Bayes factor as a tool for hypothesis evaluation and model selection. The present review highlights the potential of the Bayes factor in psychological research. We discuss six types of applications: Bayesian evaluation of point null, interval, and informative hypotheses, Bayesian evidence synthesis, Bayesian variable selection and model averaging, and Bayesian evaluation of cognitive models. We elaborate what each application entails, give illustrative examples, and provide an overview of key references and software with links to other applications. The paper is concluded with a discussion of the opportunities and pitfalls of Bayes factor applications and a sketch of corresponding future research lines