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"Johnson, Malcolm"
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Addressing fraudulent responses in online surveys: Insights from a web‐based participatory mapping study
by
Byrne, Jason
,
Adams, Vanessa M.
,
Johnson, Malcolm S.
in
COVID-19
,
data analysis
,
Data integrity
2024
Web‐based studies of human dimensions are increasing across environmental and socio‐ecological disciplines. However, the prevalence of fraud threatens research quality. Increased fraud rates should be expected as surveys move progressively more online, motivated by expanding reach, cost savings and/or in response to COVID‐19. Web‐based research must better account for fraud to maintain confidence in findings. Practical diagnostic tools and data quality protocols are required to detect fraud and ensure results quality. Drawing on our experience using an online participatory mapping case study, we discuss methods to detect potentially fraudulent responses—and identify some limitations. We begin by reviewing the current state of knowledge on fraudulent responses or ‘fraudsters’ and its relative absence in environmental and socio‐ecological disciplines. We then describe our research approach, the indicators and variables we used to detect and assess fraud and our decision‐making process to eliminate suspicious responses without jeopardizing research integrity. We found that despite several preventative measures, many fraudulent respondents could provide survey responses and effectively mimicked legitimate respondents at first glance. By assuming each response to be ‘potentially fraudulent’, we determined that the complete screening of each respondent, while time‐consuming, can limit the prevalence of fraud. We also determined that the most common data consistency checks (e.g. duration, trap questions and straight‐liner checks) are unlikely to guarantee valid respondents. If not acknowledged and addressed, fraud has the potential to undermine data integrity, discredit research findings and limit the utility of results for policy. This study contributes to environmental and socio‐ecological research by reviewing existing fraudster literature and using our experience with fraud to provide recommendations for researchers to address this problem. We encourage researchers implementing online qualitative research methods to thoroughly assess and report fraud, when possible, to ensure widespread knowledge of this growing threat. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog.
Journal Article
The benefits of Q + PPGIS for coupled human-natural systems research: A systematic review
by
Byrne, Jason
,
Adams, Vanessa M
,
Johnson, Malcolm S
in
Citizen participation
,
Conflict
,
Data collection
2022
Managing complex problems in socio-ecological systems (SES) requires innovative approaches, which account for multiple scales, large datasets, and diverse lived experiences. By combining two commonly utilized mixed-methods, public participation GIS (PPGIS) and Q-method (Q), Q + PPGIS has the potential to reveal competing agendas and reduce conflict, but its benefits and weaknesses are comparatively understudied. Using a systematic review, we evaluated how different studies have employed and implemented the Q + PPGIS method. We found 16 studies, comprising 30 publications, with considerable variation in their geographic foci, research disciplines, and addressed SES challenges. These studies exhibit a lack of cohesion between methodological design and implementation and the absence of a consistent application of the method. Nonetheless, Q + PPGIS offers a tool that can guide policy, better inform stakeholders, and reduce conflict based on misconceptions. Resolving the shortcomings identified here will broaden Q + PPGIS utility in geographically situating and representing multiple realities within complex socio-ecological systems challenges.
Journal Article
Laparoscopic Sleeve Gastrectomy Versus Banded Roux-en-Y Gastric Bypass for Diabetes and Obesity: a Prospective Randomised Double-Blind Trial
by
Robinson, S John
,
Kim, David D
,
Clarke, Michael G
in
Clinical trials
,
Comparative studies
,
Diabetes
2018
BackgroundThere are very few randomised, blinded trials comparing laparoscopic sleeve gastrectomy (LSG) versus laparoscopic Roux-en-Y gastric bypass (LRYGB) in achieving remission of type 2 diabetes (T2D), particularly silastic ring (SR)-LRYGB. We compared the effectiveness of (LSG) versus SR-LRYGB among patients with T2D and morbid obesity.MethodsProspective, randomised, parallel, 2-arm, blinded clinical trial conducted in a single Auckland (New Zealand) centre. Eligible patients aged 20–55 years, T2D of at least 6 months duration and BMI 35–65 kg/m2 were randomised 1:1 to LSG (n = 58) or SR-LRYGB (n = 56) using random number codes disclosed after anaesthesia induction. Primary outcome was T2D remission defined by different HbA1c thresholds at 1 year. Secondary outcomes included weight loss, quality of life, anxiety and depressive symptoms, post-operative complications and mortality.ResultsMean ± standard deviation (SD) pre-operative BMI was 42.5 ± 6.2 kg/m2, HbA1c 63 ± 16 mmol/mol (30% insulin-treated, 28% had diabetes duration over 10 years). Proportions achieving HbA1c ≤ 38 mmol/mol, < 42 mmol/mol, < 48 mmol/mol and < 53 mmol/mol without diabetes medication at 1 year in SR-LRYGB vs LSG were 38 vs 43% (p = 0.56), 52 vs 49% (p = 0.85), 75 vs 72% (p = 0.83) and 80 vs 77% (p = 0.82), respectively. Mean ± SD % total weight loss at 1 year was greater after SR-LRYGB than LSG: 32.2 ± 7.7 vs 27.1 ± 7.5%, respectively (p < 0.001). Gastrointestinal complications were more frequent after SR-LRYGB (including 3 ulcers, 1 anastomotic leak, 1 abdominal bleeding). Quality of life and depression symptoms improved significantly in both groups.ConclusionDespite significantly greater weight loss after SR-LRYGB, there was similar T2D remission and psychosocial improvement after LSG and SR-LRYGB at 1 year.Trial RegistrationProspectively registered at Australia and New Zealand Clinical Trials Register (ACTRN 12611000751976) and retrospectively registered at Clinical Trials (NCT1486680).
Journal Article
Rhinovirus Infection Induces Degradation of Antimicrobial Peptides and Secondary Bacterial Infection in Chronic Obstructive Pulmonary Disease
2012
Chronic obstructive pulmonary disease (COPD) exacerbations are associated with virus (mostly rhinovirus) and bacterial infections, but it is not known whether rhinovirus infections precipitate secondary bacterial infections.
To investigate relationships between rhinovirus infection and bacterial infection and the role of antimicrobial peptides in COPD exacerbations.
We infected subjects with moderate COPD and smokers and nonsmokers with normal lung function with rhinovirus. Induced sputum was collected before and repeatedly after rhinovirus infection and virus and bacterial loads measured with quantitative polymerase chain reaction and culture. The antimicrobial peptides secretory leukoprotease inhibitor (SLPI), elafin, pentraxin, LL-37, α-defensins and β-defensin-2, and the protease neutrophil elastase were measured in sputum supernatants.
After rhinovirus infection, secondary bacterial infection was detected in 60% of subjects with COPD, 9.5% of smokers, and 10% of nonsmokers (P < 0.001). Sputum virus load peaked on Days 5-9 and bacterial load on Day 15. Sputum neutrophil elastase was significantly increased and SLPI and elafin significantly reduced after rhinovirus infection exclusively in subjects with COPD with secondary bacterial infections, and SLPI and elafin levels correlated inversely with bacterial load.
Rhinovirus infections are frequently followed by secondary bacterial infections in COPD and cleavage of the antimicrobial peptides SLPI and elafin by virus-induced neutrophil elastase may precipitate these secondary bacterial infections. Therapy targeting neutrophil elastase or enhancing innate immunity may be useful novel therapies for prevention of secondary bacterial infections in virus-induced COPD exacerbations.
Journal Article
Beta Defensin-2 Is Reduced in Central but Not in Distal Airways of Smoker COPD Patients
2012
Altered pulmonary defenses in chronic obstructive pulmonary disease (COPD) may promote distal airways bacterial colonization. The expression/activation of Toll Like receptors (TLR) and beta 2 defensin (HBD2) release by epithelial cells crucially affect pulmonary defence mechanisms.
The epithelial expression of TLR4 and of HBD2 was assessed in surgical specimens from current smokers COPD (s-COPD; n = 17), ex-smokers COPD (ex-s-COPD; n = 8), smokers without COPD (S; n = 12), and from non-smoker non-COPD subjects (C; n = 13).
In distal airways, s-COPD highly expressed TLR4 and HBD2. In central airways, S and s-COPD showed increased TLR4 expression. Lower HBD2 expression was observed in central airways of s-COPD when compared to S and to ex-s-COPD. s-COPD had a reduced HBD2 gene expression as demonstrated by real-time PCR on micro-dissected bronchial epithelial cells. Furthermore, HBD2 expression positively correlated with FEV1/FVC ratio and inversely correlated with the cigarette smoke exposure. In a bronchial epithelial cell line (16 HBE) IL-1β significantly induced the HBD2 mRNA expression and cigarette smoke extracts significantly counteracted this IL-1 mediated effect reducing both the activation of NFkB pathway and the interaction between NFkB and HBD2 promoter.
This study provides new insights on the possible mechanisms involved in the alteration of innate immunity mechanisms in COPD.
Journal Article
Alternative Mechanisms for Long-Acting β2-Adrenergic Agonists in COPD
2001
β2-Adrenergic agonists are commonly used asbronchodilators to treat patients with COPD. In addition to prolongedbronchodilation, long-acting β2-agonists (LABAs) exertother effects that may be of clinical relevance. These includeinhibition of airway smooth-muscle cell proliferation and inflammatorymediator release, as well as nonsmooth-muscle effects, such asstimulation of mucociliary transport, cytoprotection of the respiratorymucosa, and attenuation of neutrophil recruitment and activation. Thisreview details the possible alternative mechanisms of action of the LABAs, salmeterol and formoterol, in COPD.
Journal Article
Glucocorticoid Receptor Nuclear Translocation in Airway Cells after Inhaled Combination Therapy
by
Usmani, Omar S
,
Barnes, Peter J
,
Johnson, Malcolm
in
Adrenal Cortex Hormones - therapeutic use
,
Adrenergic beta-Agonists - pharmacology
,
Adrenergic beta-Agonists - therapeutic use
2005
Clinical evidence is accumulating for the efficacy of adding inhaled long-acting beta(2)-agonists (LABAs) to corticosteroids in asthma. Corticosteroids bind to cytoplasmic glucocorticoid receptors (GRs), which then translocate to the nucleus where they regulate gene expression. This article reports the first evidence in vivo of an interaction between inhaled LABA and corticosteroid on GR nuclear translocation in human airway cells using immunocytochemistry. We initially demonstrated significant GR activation 60 minutes after inhalation of 800 microg beclomethasone dipropionate in six healthy subjects. Subsequently, we determined the effects of salmeterol and fluticasone propionate (FP) in seven steroid-naive patients with asthma. We observed dose-dependent GR activation with 100- and 500-microg doses of FP, and to a lesser extent with 50 microg salmeterol alone. However, combination therapy with 100 microg FP and salmeterol augmented the action of FP on GR nuclear localization. In vitro, salmeterol enhanced FP effects on GR nuclear translocation in epithelial and macrophage-like airway cell lines. In addition, salmeterol in combination with FP enhanced glucocorticoid response element (GRE)-luciferase reporter gene activity and mitogen-activated protein kinase phosphatase 1 (MKP-1) and secretory leuko-proteinase inhibitor (SLPI) gene induction. Together, our data confirm that GR nuclear translocation may underlie the complementary interactions between LABAs and corticosteroids, although the precise signal transduction mechanisms remain to be determined.
Journal Article
Measurement Properties of the SF-MPQ-2 Neuropathic Qualities Subscale in Persons with CRPS: Validity, Responsiveness, and Rasch Analysis
2019
Abstract
Objectives
The purpose of this study was to conduct classical psychometric evaluation and Rasch analysis on the Neuropathic Qualities subscale of the Short-Form McGill Pain Questionnaire-2 utilizing scores from persons with complex regional pain syndrome to consider reliability and person separation, validity (including unidimensionality), and responsiveness in this population.
Methods
Secondary analysis of longitudinal data from persons with acute complex regional pain syndrome was utilized for analysis of the psychometric properties and fit to the Rasch model of the Neuropathic Qualities subscale. We followed an iterative process of Rasch analysis to evaluate and address data fitting challenges.
Results
Repeated measures from 59 persons meeting the Budapest criteria were used for analysis. Both item-total correlations and unidimensionality analyses supported theoretical construct validity; all convergent construct validity hypotheses were also supported. Responsiveness was demonstrated comparing baseline and one-year data at d = 0.92, with a standardized response mean of 0.97. Data were able to fit the Rasch model, but all Neuropathic Qualities items had disordered thresholds that required rescoring. Additionally, local dependency and differential item function were addressed by “bundling,” suggesting that no further item reduction would be possible.
Conclusions
This study provided preliminary support for the validity and responsiveness of the Neuropathic Qualities subscale in persons with complex regional pain syndrome. Rasch analysis further endorses use of the Neuropathic Qualities subscale as a “stand-alone” measure for neuropathic features, but with substantial background data transformations. Replication with larger samples is recommended to increase confidence in these findings.
Journal Article
Antiinflammatory Effects of Salmeterol/Fluticasone Propionate in Chronic Obstructive Lung Disease
by
on behalf of SCO30005 Study Group
,
Johnson, Malcolm
,
Parker, Debbie
in
Administration, Inhalation
,
Adrenergic beta-Agonists - administration & dosage
,
Adrenergic beta-Agonists - therapeutic use
2006
No currently available treatment is reported to reduce the exaggerated airway wall inflammation of chronic obstructive pulmonary disease.
We tested the hypothesis that inhaled combined long-acting beta2-agonist (salmeterol) and corticosteroid (fluticasone propionate) will reduce inflammation.
Bronchial biopsies and induced sputum were taken from 140 current and former smokers (mean age, 64 yr) with moderate to severe disease, randomized in a 13-wk double-blind study to placebo (n = 73) or salmeterol/fluticasone propionate 50/500 microg (n = 67) twice daily. Biopsies were repeated at 12 wk and sputa at 8 and 13 wk. After adjustment for multiplicity, comparisons between active and placebo were made for median change from baseline in the numbers of biopsy CD8+ and CD68+ cells/mm2 and sputum neutrophils.
Combination therapy was associated with a reduction in biopsy CD8+ cells of -118 cells/mm2 (95% confidence interval [CI], -209 to -42; p = 0.02), a reduction of 36% over placebo (p = 0.001). CD68+ cells were unaffected by combination treatment. Sputum differential (but not total) neutrophils reduced progressively and, at Week 13, significantly with combination treatment (median treatment difference, 8.5%; 95% CI, 1.75%-15.25%; p = 0.04). The combination also significantly reduced biopsy CD45+ and CD4+ cells and cells expressing genes for tumor necrosis factor-alpha and IFN-gamma and sputum total eosinophils (all p < or = 0.03). These antiinflammatory effects were accompanied by a 173-ml (95% CI, 104-242; p < 0.001) improvement in prebronchodilator FEV1.
The combination of salmeterol and fluticasone propionate has a broad spectrum of antiinflammatory effects in both current and former smokers with chronic obstructive pulmonary disease, which may contribute to clinical efficacy.
Journal Article
β2-Adrenoceptor agonist-induced RGS2 expression is a genomic mechanism of bronchoprotection that is enhanced by glucocorticoids
by
Johnson, Malcolm
,
Holden, Neil S.
,
Giembycz, Mark A.
in
Adrenergic beta-2 Receptor Agonists - pharmacology
,
Agonists
,
Albuterol - analogs & derivatives
2011
In asthma and chronic obstructive pulmonary disease, activation of Gq-protein—coupled receptors causes bronchoconstriction. In each case, the management of moderate-to-severe disease uses inhaled corticosteroid (glucocorticoid)/long-acting β2-adrenoceptor agonist (LABA) combination therapies, which are more efficacious than either monotherapy alone. In primary human airway smooth muscle cells, glucocorticoid/LABA combinations synergistically induce the expression of regulator of G-protein signaling 2 (RGS2), a GTPase-activating protein that attenuates Gq signaling. Functionally, RGS2 reduced intracellular free calcium flux elicited by histamine, methacholine, leukotrienes, and other spasmogens. Furthermore, protection against spasmogen-increased intracellular free calcium, following treatment for 6 h with LABA plus corticosteroid, was dependent on RGS2. Finally, Rgs2-deficient mice revealed enhanced bronchoconstriction to spasmogens and an absence of LABA-induced bronchoprotection. These data identify RGS2 gene expression as a genomic mechanism of bronchoprotection that is induced by glucocorticoids plus LABAs in human airway smooth muscle and provide a rational explanation for the clinical efficacy of inhaled corticosteroid (glucocorticoid)/LABA combinations in obstructive airways diseases.
Journal Article