19 research outputs found
Special Libraries, October 1940
Volume 31, Issue 8https://scholarworks.sjsu.edu/sla_sl_1940/1007/thumbnail.jp
Does precautionary information about electromagnetic fields trigger nocebo responses? An experimental risk communication study
Background
Regarding electromagnetic fields from mobile communication technologies, empirical studies have shown that precautionary information given to lay recipients increases their risk perceptions, i.e. the belief that electromagnetic fields are dangerous. Taking this finding one step further, the current study investigates whether precautionary information also leads to higher symptom perceptions in an alleged exposure situation. Building on existing research on nocebo responses to sham electromagnetic fields, an interaction of the precautionary information with personality characteristics was hypothesised.
Methods
An experimental design with sham exposure to an electromagnetic field of a WLAN device was deployed. The final sample is constituted by N = 137 participants. Participants received either only basic information about the safety of current WLAN exposure limits or in addition also precautionary information (e.g. ‘prefer wired connections if wireless technology can be relinquished’). Subsequently, symptoms and other variables were assessed before and after sham exposure to a WLAN electromagnetic field.
Results
Results are not in favour of the hypothesised effects. There was neither a main effect of precautionary information, nor were there any of the hypothesised interaction effects of precautionary information and personality characteristics on perceived symptoms under sham exposure. Exploratory analyses highlight the role of prior risk perception as a predictor of nocebo responses, and of symptom expectations as a mediator between these two variables.
Conclusions
As the statistical power to detect even small effects was relatively high, we interpret this as a robust indication that precautionary information does not lead to increased nocebo responses by itself. The implications for health authorities´ communication with the public are discussed
A collaborative approach to adopting/adapting guidelines - the Australian 24-hour Movement Guidelines for the early years (birth to 5 years): an integration of physical activity, sedentary behavior, and sleep
BACKGROUND: In 2017, the Australian Government funded the update of the National Physical Activity Recommendations for Children 0-5 years, with the intention that they be an integration of movement behaviours across the 24-h period. The benefit for Australia was that it could leverage research in Canada in the development of their 24-h guidelines for the early years. Concurrently, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) working group published a model to produce guidelines based on adoption, adaption and/or de novo development using the GRADE evidence-to-decision framework. Referred to as the GRADE-ADOLOPMENT approach, it allows guideline developers to follow a structured and transparent process in a more efficient manner, potentially avoiding the need to unnecessarily repeat costly tasks such as conducting systematic reviews. The purpose of this paper is to outline the process and outcomes for adapting the Canadian 24-Hour Movement Guidelines for the Early Years to develop the Australian 24-Hour Movement Guidelines for the Early Years guided by the GRADE-ADOLOPMENT framework. METHODS: The development process was guided by the GRADE-ADOLOPMENT approach. A Leadership Group and Consensus Panel were formed and existing credible guidelines identified. The draft Canadian 24-h integrated movement guidelines for the early years best met the criteria established by the Panel. These were evaluated based on the evidence in the GRADE tables, summaries of findings tables and draft recommendations from the Canadian Draft Guidelines. Updates to each of the Canadian systematic reviews were conducted and the Consensus Panel reviewed the evidence for each behaviour separately and made a decision to adopt or adapt the Canadian recommendations for each behaviour or create de novo recommendations. An online survey was then conducted (n = 302) along with five focus groups (n = 30) and five key informant interviews (n = 5) to obtain feedback from stakeholders on the draft guidelines. RESULTS: Based on the evidence from the Canadian systematic reviews and the updated systematic reviews in Australia, the Consensus Panel agreed to adopt the Canadian recommendations and, apart from some minor changes to the wording of good practice statements, keep the wording of the guidelines, preamble and title of the Canadian Guidelines. The Australian Guidelines provide evidence-informed recommendations for a healthy day (24-h), integrating physical activity, sedentary behaviour (including limits to screen time), and sleep for infants (<1 year), toddlers (1-2 years) and preschoolers (3-5 years). CONCLUSIONS: To our knowledge, this is only the second time the GRADE-ADOLOPMENT approach has been used. Following this approach, the judgments of the Australian Consensus Panel did not differ sufficiently to change the directions and strength of the recommendations and as such, the Canadian recommendations were adopted with very minor alterations. This allowed the Guidelines to be developed much faster and at lower cost. As such, we would recommend the GRADE-ADOLOPMENT approach, especially if a credible set of guidelines, with all supporting materials and developed using a transparent process, is available. Other countries may consider using this approach when developing and/or revising national movement guidelines
The Determinants of Electromagnetic Hypersensitivity
Electromagnetic Hypersensitivity (EHS), more formally known as Idiopathic Environmental Intolerance attributed to Electromagnetic Fields (IEI-EMF), is a controversial condition characterised by the experience of a broad range of non-specific symptoms which a person attributes to the electromagnetic fields (EMF) emitted by everyday electronic and wireless technologies. In contrast to growing anecdotal reports of sensitivity to EMF, much of the existing literature has not found evidence that exposure to EMF can result in the symptoms reported by IEI-EMF sufferers. Instead, the condition is thought to be the result of a nocebo effect, where conscious or subconscious symptom expectation leads to the development and detection of symptoms. Yet, despite decades of research, IEI-EMF sufferers and a minority of scientists argue that the symptoms are caused by exposure to EMF, via some as-yet unrecognised bioelectromagnetic mechanism.
In an effort to resolve the aetiological debate, this thesis aimed to clarify whether toxicogenic or psychogenic processes can explain the symptoms reported by IEI-EMF sufferers. Specifically, a number of methodological issues were addressed to more clearly determine whether individuals can be sensitive to EMF exposure, or whether psychogenic processes play a role in the presentation of symptoms attributed to EMF exposure
Can explicit suggestions about the harmfulness of EMF exposure exacerbate a nocebo response in healthy controls?
2018 Elsevier Inc. While there has been consistent evidence that symptoms reported by individuals who suffer from Idiopathic Environmental Intolerance attributed to Electromagnetic Fields (IEI-EMF) are not caused by EMF and are more closely associated with a nocebo effect, whether this response is specific to IEI-EMF sufferers and what triggers it, remains unclear. The present experiment tested whether perceived EMF exposure could elicit symptoms in healthy participants, and whether viewing an \u27alarmist\u27 video could exacerbate a nocebo response. Participants were randomly assigned to watch either an alarmist (N = 22) or control video (N = 22) before completing a series of sham and active radiofrequency (RF) EMF exposure provocation trials (2 open-label, followed by 12 randomized, double-blind, counterbalanced trials). Pre- and post-video state anxiety and risk perception, as well as belief of exposure and symptom ratings during the open-label and double-blind provocation trials, were assessed. Symptoms were higher in the open-label RF-ON than RF-OFF trial (p \u3c.001). No difference in either symptoms (p =.183) or belief of exposure (p =.144) was observed in the double-blind trials. Participants who viewed the alarmist video had a significant increase in symptoms (p =.041), state anxiety (p \u3c.01) and risk perception (p \u3c.001) relative to the control group. These results reveal the crucial role of awareness and belief in the presentation of symptoms during perceived exposure to EMF, showing that healthy participants exhibit a nocebo response, and that alarmist media reports emphasizing adverse effects of EMF also contribute to a nocebo response
Pulse modulated radiofrequency exposure influences cognitive performance
Purpose: To investigate whether exposure to pulse modulated radiofrequency (PM RF) influences human cognitive performance, and whether it does so in a dose-dependent manner. Materials and methods: Thirty-six healthy adults participated in a randomized, double-blind, counterbalanced provocation study. Cognitive performance was assessed using a visual discrimination task and a modified Sternberg working memory task, which were calibrated to individual performance levels in a preliminary testing session. An sXh920 planar exposure system was used to generate a 920 MHz GSM-like signal, providing three conditions (peak-spatial SAR averaged over 10 g) of 0 W/kg (sham), 1 W/kg (low RF) and 2 W/kg (high RF). Results: A significant decrease in reaction time (RT) in the Sternberg working memory task was found during exposure compared to sham. This effect was not dose-dependent. Conclusions: Cognitive performance was shown to be faster under PM RF conditions, relative to sham, in a working memory task. While the majority of the literature has not found effects of PM RF exposure on cognitive performance, it is possible that the methodological improvements employed in the present study increased sensitivity, and thus the ability to detect potential effects
Does acute radio-frequency electromagnetic field exposure affect visual event-related potentials in healthy adults?
Objective: To use improved methods to address the question of whether acute exposure to radio-frequency (RF) electromagnetic fields (RF-EMF) affects early (80-200 ms) sensory and later (180-600 ms) cognitive processes as indexed by event-related potentials (ERPs).
Methods: Thirty-six healthy subjects completed a visual discrimination task during concurrent exposure to a Global System for Mobile Communications (GSM)-like, 920 MHz signal with peak-spatial specific absorption rate for 10 g of tissue of 0 W/kg of body mass (Sham), 1 W/kg (Low RF) and 2 W/kg (High RF). A fully randomised, counterbalanced, double-blind design was used.
Results: P1 amplitude was reduced (p =.02) and anterior N1 latency was increased (p =.04) during Exposure compared to Sham. There were no effects on any other ERP latencies or amplitudes. Conclusions: RF-EMF exposure may affect early perceptual (P1) and preparatory motor (anterior N1) processes. However, only two ERP indices, out of 56 comparisons, were observed to differ between RF-EMF exposure and Sham, suggesting that these observations may be due to chance.
Significance: These observations are consistent with previous findings that RF-EMF exposure has no reliable impact on cognition (e.g., accuracy and response speed)