"Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has."
"Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has."
No author submission fees, publication time measured in days, not months, and crowdsourced, post-publication review - and that’s just the tip of the iceberg!
Showcase your department and reach a global audience with a Cureus channel. Click below to find out how your organization can stand out from the crowded publishing field.
Stimulate focused retrospective studies that provide detailed, objective insight into clinical experiences. Contact us below to learn more about competition sponsorship.
Cureus is on a mission to change the long-standing paradigm of medical publishing, where submitting research can be costly, complex and time-consuming.
Medical Education and Simulation
Commentary: Major problems with recent systematic review on wind farms and distress.
Simon Chapman AO PhD FASSA
Professor of Public Health
University of Sydney
At least 20 reviews of the evidence on whether wind turbines cause health problems including stress have been published since 2003 (1). Cureus recently published another (2) where the authors referenced none of these.
Highlights of the findings of these reviews may be found here (1). The most recent (2014) review by Australia’s peak health and medical agency, The National Health and Medical Research Council (3) concluded:
“There is no consistent evidence that noise from wind turbines… is associated with self reported human health effects. Isolated associations may be due to confounding, bias or chance. There is consistent evidence that noise from wind turbines―whether estimated in models or using distance as a proxy―is associated with annoyance, and reasonable consistency that it is associated with sleep disturbance and poorer sleep quality and quality of life. However, it is unclear whether the observed associations are due to wind turbine noise or plausible confounders.”
“The association between estimated noise level and annoyance was significantly affected by the visual attitude of the individual (i.e. whether they found wind farms beautiful, or ugly and unnatural) in the three studies that assessed this as a potential confounding factor. Residents in [one] study with a negative attitude to the visual impact of wind farms on the landscape had over 14 times the odds of being annoyed compared with those people without a negative visual attitude. …This means that factors other than the noise produced by wind turbines contribute to the annoyance experienced by survey respondents.”
Against this background, I was curious to see what a new systematic review would conclude. According to the Cureus website, the new paper was peer reviewed. This is difficult to understand because of the sheer volume of major and minor problems it contains. Together, these make its contribution valueless to scholarly understanding of the phenomenon of noise and health complaints about wind farms. The paper shows many signs of poor understanding of the subject matter of their review, of critical appraisal methods, of some basic conventions in systematic reviewing, of structuring in scientific writing, and much more besides.
The problems commence in the first line of the abstract where the confusing statement is made that “the proximity of wind turbines to residential areas has been associated with a higher level of complaints compared to the general population.” I assume here that they are trying to say that those living near turbines have a higher prevalence of health complaints like sleep disturbance and general “human distress” than in the wider population. The prevalence of sleeping problems in general populations is as high as 33% (4) and reference material exists that quantifies the prevalence of many health problems in general populations (5, 6). Instead, the authors support their statement with a reference to a small qualitative study of 15 people both affected and unaffected by turbines (7). No conclusions about the prevalence of health problems in communities near turbines or in matched comparison populations can be drawn from that paper. I know of no published evidence that would allow such a statement to be made.
The authors state that their search strategy located 18 eligible papers but that these were based on six original studies. They explain that the 12 non-original “studies” (several of which were reviews or commentaries) were then excluded. Yet in their “key results” they proceed to describe the characteristics of all 18 papers and thus act as if these were not excluded (“All 18 peer-reviewed studies captured in our review found an association…”).
The authors do not appear to understand what an “outcome” is. The abstract lists “outcome” variables that are not outcomes at all (such as study quality and journal name). These are independent variables, not dependent ones.
Their eligibility criteria for study selection are perplexing. What for example, is the difference between “peer-reviewed studies” and “studies published in peer-reviewed journals”? So too, is their noting that they searched the Cochrane Library for relevant studies. The Cochrane Library is a repository of reviews of evidence for health interventions, not for data on the prevalence of health complaints.
The authors seem not to understand the difference between studies and trials. For obvious reasons, there have been no trials conducted in this area.
Their main conclusions are that:
• An association exists between wind turbines and distress in humans.
• The existence of a dose-response relationship (between distance from wind turbines and distress) and the consistency of the association across studies .. argues for the credibility of this association.
The first conclusion is very imprecise and sweeping and ripe for being megaphoned by anti-wind farm interest groups as if it actually meant something. One of the six original studies reviewed (Salt & Hullar) (8) should have never been included in this review – see below. The Nissenbaum et a study (9) is listed as of moderate quality with a low risk of bias. Yet all three authors and two out of three reviewers of that paper are members of Society for Wind Vigilance, an anti-wind organization. Nissenbaum has been raising health concerns in study areas for several years, potentially biasing collected data. Neither of these problems is mentioned in this review. Two critiques of this study were published in Noise and Health pointing out the very poor quality of the results, analysis and the overstatements of conclusions (10, 11).
The Shepherd et al study (12) which the authors rate as of “high” quality, failed to make any mention that the small wind farm community involved had for years been subjected to a local wind farm opposition group fomenting anxiety about health issues (13). Indeed, with one exception (14), the five studies referenced were performed in areas where complaints of annoyance were being raised. But such farms are unlikely to be representative of all wind farms. As our work shows, over nearly 65% of wind farms in Australia have never received a single complaint (15), and 73% of complainants in Australia are concentrated around just 6/51 farms. The failure of the authors to note this fundamental problem of study sample selection bias is another major problem.
Among the five “original” studies they considered satisfied their selection criteria was a paper by Salt & Hullar (8). This paper is not in any way a “study” of “the association between wind turbines and human distress.” It reports no original empirical data and is essentially a backgrounder on infrasound and the “possibility” that wind turbine might create auditory distress. It is unfathomable why this paper was included in the data set.
Table 2 purports to be a meaningful summary of the findings of these six studies on the association between turbine exposure and “distress”. I would defy anyone to make any sense of the Table, particularly the column headed “does [sic] response”.
By way of comparison to the lack of detail provided by the authors of this review, it is instructive to look at the results from the Dutch study which formed the basis of the Pedersen 2009 paper(14) which were further analysed by Bakker et al (16) who noted that sleep disturbance was assessed by a question dealing with the frequency of sleep disturbance by environmental sound (“how often are you disturbed by sound?”). Two thirds of all respondents reported not being disturbed by any sound at all. Disturbance by traffic noise or other mechanical sound was reported by 15.2% of the respondents. Disturbance by the sound of people and of animals was reported by 13.4% of the respondents. Relevantly, disturbance by the sound of wind turbines was reported by only 4.7% of the respondents (6% in areas deemed to be quiet and 4% in areas deemed to be noisy). Bakker and colleagues (16) note that it was not clear from the study if there was a primary source causing sleep disturbance and how respondents attributed being awakened by different environmental sound sources. What was clear was that wind turbines were less frequently reported as a sleep disturbing sound source, than other environmental sounds irrespective of the area type (quiet versus noisy). Analysis showed that among respondents who could hear wind turbine sound, annoyance was the only factor that predicted sleep disturbance. The authors speculated that being annoyed might contribute to a person’s sensitivity for any environmental sound, and the reaction might be caused by the combination of all sounds present. It might also be the case that people annoyed by wind turbine noise attribute their experience of sleep disturbance to wind turbine noise, even if that was not the source of their awakening.
Swathes of the paper are given over to descriptions of their efforts to rate the levels of evidence in the four reviewed studies. But they never ever describe their approach in any way that might permit replication of how they went about such rating. How was level of evidence actually determined? It should have been explicitly defined in the text. Their discussion of the risk of bias across studies is bizarre. "The quality of the study could be confounded by journal name and author". Surely the authors mean here that the evaluation of the quality of the study could be biased by this knowledge. The term “confounded” has another meaning.
Their “key results” consist of no more than five bullet points. These read like draft notes-to-self (eg: None of these studies captured in our review found any association (potential publication bias)”.
The authors chose to use the term “distress” instead of “annoyance". The American Medical Dictionary defines distress as 1. Mental or physical suffering or anguish or 2. Severe strain resulting from exhaustion or trauma. Annoyance on the other hand is defined as 1. The act of annoying or the state of being annoyed or 2. A cause of irritation or vexation; a nuisance. (The American Heritage Dictionary of the English Language, Fourth Edition copyright 2000) and is generally identified as a highly subjective state in medical literature. It is clear that the authors chose a stronger term than was used by the majority of studies. Most literature refers to annoyance, while the referenced alternative of “Wind Turbine Syndrome” was coined in a vanity press published case study with extraordinary weaknesses of selection bias, methodology and analysis (17). Similarly, “extreme annoyance” is rarely used in the literature. Annoyance is by far the most commonly used term in the material referenced, so it is unclear why “distress” was chosen.
The paper is riddled with imprecise, mangled and contradictory language. For example: key finding 1: “All 18 peer-reviewed studies captured in our review found an association…” and key finding 2: “None of these studies captured in our review found any association (potential publication bias)”; infelicitous prose: “these complaints are coined in research”; “There might be a theoretical incline to give studies in high impact journals higher quality…”; basic grammatical errors: “the study’s principle outcome”; “there was no missing data.” It is unconventionally structured with extremely scant results and methods sections providing no adequate explanations of how key decisions on quality or bias were made.
The publication of this very poor paper is regrettable.
Acknowledgements: Fiona Crichton, Cornelia Baines and Mike Bernard each contributed comments to me for this response.
Competing interests: Simon Chapman receives no financial or in-kind support from any company, individual or agency associated with wind energy.
1. Chapman S, Simonetti T. Summary of main conclusions reached in 20 reviews of the research literature on wind farms and health. Sydney University eScholarship respository: University of Sydney; 2014; Available from: http://hdl.handle.net/2123/10559.
2. Arra I, Lynn H, Barker K, Ogbuneke C, Regalado S. Systematic review 2013: Association between wind turbines and human distress. 2014; Available from: http://www.cureus.com/articles/2457-systematic-review-2013-association-between-wind-turbines-and-human-distress?utm_medium=email&utm_source=transaction - .U6DaMi90xT5.
3. Merlin T, Newton S, Ellery B, Milverton J, Farah C. Systematic review of the human health effects of wind farms. Canberra: National Health and Medical Reserach Council; 2014; Available from: https://http://www.nhmrc.gov.au/_files_nhmrc/publications/attachments/eh54_systematic_review_of_the_human_health_effects_of_wind_farms_december_2013.pdf.
4. Bartlett DJ, Marshall NS, Williams A, Grunstein RR. Predictors of primary medical care consultation for sleep disorders. Sleep medicine. 2008;9(8):857-64. Epub 2007/11/06.
5. Rief W, Barsky AJ, Glombiewski JA, Nestoriuc Y, Glaesmer H, Braehler E. Assessing general side effects in clinical trials: reference data from the general population. Pharmacoepidemiol Drug Saf. 2011;20(4):405-15. Epub 2011/03/29.
6. Petrie KJ, Faasse K, Crichton F, Grey A. How common are symptoms? Evidence from a New Zealand national telephone survey. BMJ open. 2014;4(6):e005374. Epub 2014/06/15.
7. Pedersen E, Hallberg LR-M, Waye KP. Living in the vicinity of wind turines - a grounded theory study. Qualitative Research in Psychology. 2007;4:49-63.
8. Salt AN, Hullar TE. Responses of the ear to low frequency sounds, infrasound and wind turbines. Hearing research. 2010;268(1-2):12-21. Epub 2010/06/22.
9. Nissenbaum MA, Aramini JJ, Hanning CD. Effects of industrial wind turbine noise on sleep and health. Noise Health. 2012;14(60):237-43. Epub 2012/11/03.
10. Ollson CA, Knopper LD, McCallum LC, Whitfield-Aslund ML. Are the findings of "Effects of industrial wind turbine noise on sleep and health" supported? Noise Health. 2013;15(63):148-50. Epub 2013/04/11.
11. Barnard M. Issues of wind turbine noise. Noise Health. 2013;15(63):150-2. Epub 2013/04/11.
12. Shepherd D, McBride D, Welch D, Dirks KN, Hill EM. Evaluating the impact of wind turbine noise on health-related quality of life. Noise Health. 2011;13(54):333-9. Epub 2011/10/01.
13. Anon. Makara Guardians. Wikipedia; Available from: http://en.wikipedia.org/wiki/Makara_Guardians.
14. Pedersen E, van den Berg F, Bakker R, Bouma J. Response to noise from modern wind farms in The Netherlands. Journal of the Acoustical Society of America. 2009;126(2):634-43. Epub 2009/07/31.
15. Chapman S, St George A, Waller K, Cakic V. The pattern of complaints about Australian wind farms does not match the establishment and distribution of turbines: support for the psychogenic, 'communicated disease' hypothesis. PloS one. 2013;8(10):e76584. Epub 2013/10/23.
16. Bakker RH, Pedersen E, van den Berg GP, Stewart RE, Lok W, Bouma J. Impact of wind turbine sound on annoyance, self-reported sleep disturbance and psychological distress. Science of the Total Environment. 2012;425:42-51.
17. Pierpont N. Wind Turbine Syndrome. A report on a natural experiment. Santa Fe: K-Selected Books; 2009.
Browsing Cureus with Internet Explorer may cause issues when rating, reviewing or submitting articles. As a result, we recommend using Google Chrome, Mozilla Firefox or Safari. We apologize for the inconvenience.