Martin Bland

The University of York, York, England, United Kingdom

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Publications (64)273.83 Total impact

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    ABSTRACT: Objectives: Human T lymphotropic virus (HTLV)-1 causes T cell leukaemia and myelopathy. Together with HTLV-2 it is endemic in some African nations. Sero- prevalence data from Malawi are scarce, with no reports on associated disease incidence. HTLV seroprevalence and type were tested in 418 healthy mothers from Malawi. In addition, we tested the sera of 534 children to investigate mother-to-child transmission. To provide context, we conducted a systematic review and meta-analysis of HTLV seroprevalence in African women and children. Methods: Stored samples from a previous childhood cancer and BBV study were analysed. ELISA was used for HTLV screening followed by immunoblot for confirmation and typing. Standard methods were used for the systematic review. Results: HTLV seroprevalence was 2.6% (11/418) in mothers and 2.2% (12/534) in children. Three mothers carried HTLV-1 alone, seven had HTLV-2 and one was dually infected. Three children carried HTLV-1 alone, seven had HTLV-2 and two were dually infected. Only two corresponding mothers of the 12 HTLV positive children were HTLV positive. The systematic review included 66 studies of women and 13 of children conducted in 25 African countries. Seroprevalence of HTLV-1 varied from 0-17% and of HTLV-2 from 0-4%. Conclusions: In contrast to findings from other studies in Africa, the seroprevalence of HTLV-2 was higher than that of HTLV-1 in Malawi and one of the highest for the African region. The lack of mother-child concordance suggests alternative sources of infection among children. Our data and analyses contribute to HTLV prevalence mapping in Africa. This article is protected by copyright. All rights reserved.
    No preview · Article · Dec 2015 · Tropical Medicine & International Health
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    ABSTRACT: Objective: To assess the risk posed by missing data (MD) to the power and validity of trials evaluating palliative interventions. Study design and setting: A systematic review of MD in published randomised controlled trials (RCTs) of palliative interventions in participants with life-limiting illnesses was conducted, and random-effects meta-analyses and meta-regression were performed. CENTRAL, Medline and EMBASE (2009-2014) were searched with no language restrictions. Results: 108 RCTs representing 15,560 patients were included. The weighted estimate for MD at the primary end-point was 23.1% (95%CI 19.3, 27.4). Larger MD proportions were associated with increasing numbers of questions/tests requested (odds ratio (OR) 1.19, 95% CI 1.05, 1.35) and with longer study duration (OR 1.09, 95% CI 1.02, 1.17). Meta-analysis found evidence of differential rates of MD between trial arms, which varied in direction (OR 1.04 (95% CI 0.90, 1.20), I(2) 35.9, p=0.001). Despite randomisation MD in the intervention arms (vs. control) were more likely to be attributed to disease-progression unrelated to the intervention (OR 1.31 (95% CI 1.02, 1.69)). This was not the case for MD due to death (OR 0.92 (95% CI 0.78, 1.08)). Conclusion: The overall proportion and differential rates and reasons for MD reduce the power and potentially introduce bias to palliative care trials.
    No preview · Article · Dec 2015 · Journal of clinical epidemiology
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    ABSTRACT: Although people with serious mental illnesses have a high risk of contracting blood-borne viral infections, sexual health has largely been neglected by researchers and policy makers involved in mental health. Failure to address this shortcoming could increase morbidity and mortality as a result of undetected and untreated infection. We did a systematic review and meta-analysis to estimate the prevalence of blood-borne viral infection in people with serious mental illness.
    Full-text · Article · Nov 2015 · The Lancet Psychiatry
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    ABSTRACT: Metastasis is the leading cause of cancer-related deaths. Voltage-gated sodium channels (VGSCs) regulate invasion and metastasis. Several VGSC-inhibiting drugs reduce metastasis in murine cancer models. We aimed to test the hypothesis that patients taking VGSC-inhibiting drugs who developed cancer live longer than those not taking these drugs. A cohort study was performed on primary care data from the QResearch database, including patients with breast, bowel or prostate cancer. Cox proportional hazards regression was used to compare the survival from cancer diagnosis of patients taking VGSC-inhibiting drugs with those not exposed to these drugs. Median time to death was 9.7 years in the exposed group and 18.4 years in the unexposed group, and exposure to these medications significantly increased mortality. Thus, exposure to VGSC-inhibiting drugs associates with reduced survival in breast, bowel and prostate cancer patients. This finding is not consistent with the preclinical data. Despite the strengths of this study including the large sample size, the study is limited by missing information on potentially important confounders such as cancer stage, co-morbidities and cause of death. Further research, which is able to account for these confounding issues, is needed to investigate the relationship between VGSC-inhibiting drugs and cancer survival.
    Full-text · Article · Nov 2015 · Scientific Reports
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    ABSTRACT: Although survival rates of breast, colon, and prostate cancers are improving, deaths from these tumors frequently occur due to metastasis. Voltage-gated Na+ channels (VGSCs) are membrane proteins, which regulate membrane current and cellular migration during nervous system organogenesis. VGSCs are also expressed in fibroblasts, immune cells, glia, and metastatic cancer cells. VGSCs regulate migration and invasion of breast, bowel, and prostate cancer cells, suggesting that they may be novel anti-metastatic targets. We conducted a systematic review of clinical and preclinical studies testing the effects of VGSC-inhibiting drugs in cancer. Two-hundred and four publications were identified, of which two human, two mouse, and 20 in vitro publications were included. In the clinical studies, the effect of these drugs on survival and metastatic relapse is not clear. The 22 preclinical studies collectively suggest that several VGSC-inhibiting drugs inhibit cancer proliferation, migration, and invasion. None of the human and only six of the preclinical studies directly investigated the effect of the drugs on VGSC activity. Studies were difficult to compare due to lack of standardized methodology and outcome measures. We conclude that the benefits of VGSC inhibitors require further investigation. Standardization of future studies and outcome measures should enable meaningful study comparisons.
    Full-text · Article · Nov 2015 · Frontiers in Pharmacology
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    ABSTRACT: Background: Management of chronic neck pain may benefit from additional active self-care-oriented approaches. Objective: To evaluate clinical effectiveness of Alexander Technique lessons or acupuncture versus usual care for persons with chronic, nonspecific neck pain. Design: Three-group randomized, controlled trial. (Current Controlled Trials: ISRCTN15186354). Setting: U.K. primary care. Participants: Persons with neck pain lasting at least 3 months, a score of at least 28% on the Northwick Park Questionnaire (NPQ) for neck pain and associated disability, and no serious underlying pathology. Intervention: 12 acupuncture sessions or 20 one-to-one Alexander lessons (both 600 minutes total) plus usual care versus usual care alone. Measurements: NPQ score (primary outcome) at 0, 3, 6, and 12 months (primary end point) and Chronic Pain Self-Efficacy Scale score, quality of life, and adverse events (secondary outcomes). Results: 517 patients were recruited, and the median duration of neck pain was 6 years. Mean attendance was 10 acupuncture sessions and 14 Alexander lessons. Between-group reductions in NPQ score at 12 months versus usual care were 3.92 percentage points for acupuncture (95% CI, 0.97 to 6.87 percentage points) (P = 0.009) and 3.79 percentage points for Alexander lessons (CI, 0.91 to 6.66 percentage points) (P = 0.010). The 12-month reductions in NPQ score from baseline were 32% for acupuncture and 31% for Alexander lessons. Participant self-efficacy improved for both interventions versus usual care at 6 months (P < 0.001) and was significantly associated (P < 0.001) with 12-month NPQ score reductions (acupuncture, 3.34 percentage points [CI, 2.31 to 4.38 percentage points]; Alexander lessons, 3.33 percentage points [CI, 2.22 to 4.44 percentage points]). No reported serious adverse events were considered probably or definitely related to either intervention. Limitation: Practitioners belonged to the 2 main U.K.-based professional associations, which may limit generalizability of the findings. Conclusion: Acupuncture sessions and Alexander Technique lessons both led to significant reductions in neck pain and associated disability compared with usual care at 12 months. Enhanced self-efficacy may partially explain why longer-term benefits were sustained. Primary funding source: Arthritis Research UK.
    No preview · Article · Nov 2015 · Annals of internal medicine
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    ABSTRACT: To advance the treatment of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), randomised controlled therapeutic studies with appropriate and sensitive outcomes are reuired. One candidate outcome is the 10-metre walk test (10MWT), a patient-centred, simple and functional measure. To calculate sample size based on 10MWT as the primary outcome, variability within and between subjects must be known. Data on 10MWT from 76 patients with HAM/TSP were prospectively collected from four specialist centres in Brazil, Japan, USA and UK. Data, collected at two time points, 6 months apart, were log transformed and subjected to analysis of covariance. Baseline mean (standard deviation = SD), median 10MWT were 23.5 (18.9), 16.3 s/10 m and at 6 months 24.9 (23.9), 16.4 s/10 m. The mean (SD) % increase in walk time was 5.74 % (28.2 %). After logarithmic transformation, the linear correlation between baseline and 24 weeks 10MWT was r = 0.938. Using these data, it was determined that a randomised controlled trial with 30 participants per group would have 90 % power to detect a 19 % decrease or a 23 % increase in 10MWT. The intra-patient variability of 10MWT is relatively small in HAM/TSP over 6 months. 10MWT is a feasible outcome measure for a clinical trial in HAM/TSP. To our knowledge, this is the first ever recommendation for the sample size required for trials in HAM/TSP patients.
    Full-text · Article · Oct 2015
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    ABSTRACT: Background: Venous leg ulcers (VLUs) are the commonest cause of leg ulceration, affecting 1 in 100 adults. There is a significant health burden associated with VLUs - it is estimated that the cost of treatment for 1 ulcer is up to (sic)1300 per year in the NHS. The mainstay of treatment is with graduated compression bandaging; however, treatment is often prolonged and up to one quarter of venous leg ulcers do not heal despite standard care. Two previous trials have suggested that low-dose aspirin, as an adjunct to standard care, may hasten healing, but these trials were small and of poor quality. Aspirin is an inexpensive, widely used medication but its safety and efficacy in the treatment of VLUs remains to be established. Methods/Design: AVURT is a phase II randomised double blind, parallel-group, placebo-controlled efficacy trial. The primary objective is to examine whether aspirin, in addition to standard care, is effective in patients with chronic VLUs (i.e. over 6 weeks in duration or a history of VLU). Secondary objectives include feasibility and safety of aspirin in this population. A target of 100 participants, identified from community leg ulcer clinics and hospital clinics, will be randomised to receive either 300 mg of aspirin once daily or placebo. All participants will receive standard care with compression therapy. The primary outcome will be time to healing of the reference ulcer. Follow-up will occur for a maximum of 27 weeks. The primary analysis will use a Cox proportional hazards model to compare time to healing using the principles of intention-to-treat. Secondary outcomes will include ulcer size, pain evaluation, compliance and adverse events. Discussion: The AVURT trial will investigate the efficacy and safety of aspirin as a treatment for VLU and will inform on the feasibility of proceeding to a larger phase III study. This study will address the paucity of information currently available regarding aspirin therapy to treat VLU.
    Full-text · Article · Oct 2015 · Trials
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    ABSTRACT: New evidence on the clinical effectiveness of acupuncture plus usual care (acupuncture) and counselling plus usual care (counselling) for patients with depression suggests the need to investigate the health-related quality of life and costs of these treatments to understand whether they should be considered a good use of limited health resources. The cost-effectiveness analyses are based on the Acupuncture, Counselling or Usual care for Depression (ACUDep) trial results. Statistical analyses demonstrate a difference in mean quality adjusted life years (QALYs) and suggest differences in mean costs which are mainly due to the price of the interventions. Probabilistic sensitivity analysis is used to express decision uncertainty. Acupuncture and counselling are found to have higher mean QALYs and costs than usual care. In the base case analysis acupuncture has an incremental cost-effectiveness ratio (ICER) of £4,560 per additional QALY and is cost-effective with a probability of 0.62 at a cost-effectiveness threshold of £20,000 per QALY. Counselling compared with acupuncture is more effective and more costly with an ICER of £71,757 and a probability of being cost-effective of 0.36. A scenario analysis of counselling versus usual care, excluding acupuncture as a comparator, results in an ICER of £7,935 and a probability of 0.91. Acupuncture is cost-effective compared with counselling or usual care alone, although the ranking of counselling and acupuncture depends on the relative cost of delivering these interventions. For patients in whom acupuncture is unavailable or perhaps inappropriate, counselling has an ICER less than most cost-effectiveness thresholds. However, further research is needed to determine the most cost-effective treatment pathways for depressed patients when the full range of available interventions is considered.
    Full-text · Article · Nov 2014 · PLoS ONE
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    Huiqin Yang · Carl Thompson · Martin Bland
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    ABSTRACT: Background Time pressure is common in acute healthcare and significantly influences clinical judgement and decision making. Despite nurses’ judgements being studied since the 1960s, the empirical picture of how time pressure impacts on nurses’ judgement strategies and outcomes remain undeveloped. This paper aims to assess alterations in nurses’ judgement strategies and outcomes under time pressure in a simulated acute care setting. Methods In a simulated acute care environment, ninety-seven nurses were exposed to 25 clinical scenarios under time pressured and no time pressured conditions. Scenarios were randomly sampled from a large dataset of patient cases. A reference standard (judgement correctness) was generated from the same patient case records. In 12 of the scenarios only 20 seconds per judgement was allowed, in the other 13 scenarios no time pressure existed. Percentage of correct judgments in both conditions was calculated. Logistic regression modelling (of 2,425 observations) described the relationship between information cues used and judgments made. The degree of attention paid to particular cues was captured by calculating cue relative weights. The clustering effect of nurses was countered by estimating robust standard errors. The Chow test was used to test the null hypothesis that differences in regression coefficients in time pressure and no time pressure models were zero. Results Compared to no time pressure, no significant difference was observed in the proportion of correct judgments when nurses were put under time pressure. However, time pressure significantly impacted on the judgment strategies employed. Whilst nurses predominantly used respiration rate to make judgements, they used fewer cues to reach their clinical judgements under time pressure. The relative weighting afforded to heart rate was much smaller in the time pressure regression model, indicating that nurses paid significantly less attention to it when making judgements under time pressure. Conclusions Time pressure had a significant effect on nurses’ judgement strategies but not outcomes. Nurses tended to use less information to reach judgements under time pressure, but not at the expense of judgment accuracy. Findings imply that nurses are capable of using adaptive judgement strategies to cope with moderate time pressures when making clinical judgements in acute care.
    Full-text · Article · Nov 2014 · BMC Medical Informatics and Decision Making
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    ABSTRACT: Introduction Metastasis from solid tumours is associated with significant morbidity and mortality, and is the leading cause of cancer-related deaths. Voltage-gated sodium channels (VGSCs) are drug targets for the treatment of epilepsy. VGSCs are also present in cancer cells, where they regulate metastatic cell behaviours, including cellular movement and invasion. Treating cancer cells with the VGSC-inhibiting anticonvulsant phenytoin reduces cellular invasion and migration. Together, these suggest that VGSCs may be useful targets for inhibiting metastasis. The purpose of this study is to test the hypothesis that use of VGSC-inhibiting drugs will reduce metastasis, and therefore increase survival time in patients with cancer. Methods and analysis A cohort study based on primary care data from the QResearch database will include patients with one of the three common tumours: breast, bowel and prostate. The primary outcome will be overall survival from the date of cancer diagnosis. Cox proportional hazards regression will be used to compare the survival of patients with cancer taking VGSC-inhibiting drugs (including anticonvulsants and class I antiarrhythmic agents) with patients with cancer not exposed to these drugs, adjusting for age and sex. Exposure to VGSC-inhibiting drugs will be defined as having at least one prescription for these drugs prior to cancer diagnosis. High and low exposure groups will be identified based on the length of use. A number of sensitivity and secondary analyses will be conducted. Ethics and dissemination The protocol has been independently peer-reviewed and approved by the QResearch Scientific Board. The project has also been approved by the University of York Ethical Review Process. The results will be presented at international conferences and published in an open access peer-reviewed journal, in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria.
    Full-text · Article · Nov 2014 · BMJ Open
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    ABSTRACT: Aim: To evaluate the effectiveness of different brief intervention strategies at reducing hazardous or harmful drinking in the probation setting. Offender managers were randomized to three interventions, each of which built on the previous one: feedback on screening outcome and a client information leaflet control group, 5 min of structured brief advice and 20 min of brief lifestyle counselling. Methods: A pragmatic multicentre factorial cluster randomized controlled trial. The primary outcome was self-reported hazardous or harmful drinking status measured by Alcohol Use Disorders Identification Test (AUDIT) at 6 months (negative status was a score of <8). Secondary outcomes were AUDIT status at 12 months, experience of alcohol-related problems, health utility, service utilization, readiness to change and reduction in conviction rates. Results: Follow-up rates were 68% at 6 months and 60% at 12 months. At both time points, there was no significant advantage of more intensive interventions compared with the control group in terms of AUDIT status. Those in the brief advice and brief lifestyle counselling intervention groups were statistically significantly less likely to reoffend (36 and 38%, respectively) than those in the client information leaflet group (50%) in the year following intervention. Conclusion: Brief advice or brief lifestyle counselling provided no additional benefit in reducing hazardous or harmful drinking compared with feedback on screening outcome and a client information leaflet. The impact of more intensive brief intervention on reoffending warrants further research.
    Full-text · Article · Jul 2014 · Alcohol and Alcoholism
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    ABSTRACT: Background Alcohol misuse is common in people attending emergency departments (EDs) and there is some evidence of efficacy of alcohol screening and brief interventions (SBI). This study investigated the effectiveness of SBI approaches of different intensities delivered by ED staff in nine typical EDs in England: the SIPS ED trial. Methods and Findings Pragmatic multicentre cluster randomized controlled trial of SBI for hazardous and harmful drinkers presenting to ED. Nine EDs were randomized to three conditions: a patient information leaflet (PIL), 5 minutes of brief advice (BA), and referral to an alcohol health worker who provided 20 minutes of brief lifestyle counseling (BLC). The primary outcome measure was the Alcohol Use Disorders Identification Test (AUDIT) status at 6 months. Of 5899 patients aged 18 or more presenting to EDs, 3737 (63·3%) were eligible to participate and 1497 (40·1%) screened positive for hazardous or harmful drinking, of whom 1204 (80·4%) gave consent to participate in the trial. Follow up rates were 72% (n = 863) at six, and 67% (n = 810) at 12 months. There was no evidence of any differences between intervention conditions for AUDIT status or any other outcome measures at months 6 or 12 in an intention to treat analysis. At month 6, compared to the PIL group, the odds ratio of being AUDIT negative for brief advice was 1·103 (95% CI 0·328 to 3·715). The odds ratio comparing BLC to PIL was 1·247 (95% CI 0·315 to 4·939). A per protocol analysis confirmed these findings. Conclusions SBI is difficult to implement in typical EDs. The results do not support widespread implementation of alcohol SBI in ED beyond screening followed by simple clinical feedback and alcohol information, which is likely to be easier and less expensive to implement than more complex interventions. Trial Registration Current Controlled Trials ISRCTN 93681536
    Full-text · Article · Jun 2014 · PLoS ONE
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    Martin Bland
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    ABSTRACT: The theory has been put forward that if a null hypothesis is true, P-values should follow a Uniform distribution. This can be used to check the validity of randomisation. The theory was tested by simulation for two sample t tests for data from a Normal distribution and a Lognormal distribution, for two sample t tests which are not independent, and for chi-squared and Fisher's exact test using small and using large samples. For the two sample t test with Normal data the distribution of P-values was very close to the Uniform. When using Lognormal data this was no longer true, and the distribution had a pronounced mode. For correlated tests, even using data from a Normal distribution, the distribution of P-values varied from simulation run to simulation run, but did not look close to Uniform in any realisation. For binary data in a small sample, only a few probabilities were possible and distribution was very uneven. With a sample of two groups of 1,000 observations, there was great unevenness in the histogram and a poor fit to the Uniform. The notion that P-values for comparisons of groups using baseline data in randomised clinical trials should follow a Uniform distribution if the randomisation is valid has been found to be true only in the context of independent variables which follow a Normal distribution, not for Lognormal data, correlated variables, or binary data using either chi-squared or Fisher's exact tests. This should not be used as a check for valid randomisation.
    Preview · Article · Oct 2013 · PLoS ONE
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    ABSTRACT: Folklore remedies for pain and inflammation in rheumatoid arthritis include the application of magnets and copper to the skin. Despite the popular use of devices containing magnets or copper for this purpose, little research has been conducted to evaluate the efficacy of such treatments. To investigate whether the practice of wearing magnetic wrists straps, or copper bracelets, offers any specific therapeutic benefit for patients with rheumatoid arthritis. Randomised double-blind placebo-controlled crossover trial. 70 patients, aged 33 to 79 years and predominantly female (n = 52), with painful rheumatoid arthritis were recruited from general practices within Yorkshire. Participants were randomly allocated to wear four devices in a different order. Devices tested were: a standard (1502 to 2365 gauss) magnetic wrist strap, a demagnetised (<20 gauss) wrist strap, an attenuated (250 to 350 gauss) magnetic wrist strap, and a copper bracelet. Devices were each worn for five weeks, with treatment phases being separated by one week wash-out periods. The primary outcome measured was pain using a 100 mm visual analogue scale. Secondary pain measures were the McGill Pain Questionnaire and tender joint count. Inflammation was assessed using C-reactive protein and plasma viscosity blood tests and by swollen joint count. Physical function was assessed using the Health Assessment Questionnaire (Disability Index). Disease activity and medication use was also measured. 65 participants provided complete self-report outcome data for all devices, four participants provided partial data. Analysis of treatment outcomes did not reveal any statistically significant differences (P>0.05) between the four devices in terms of their effects on pain, inflammation, physical function, disease activity, or medication use. Wearing a magnetic wrist strap or a copper bracelet did not appear to have any meaningful therapeutic effect, beyond that of a placebo, for alleviating symptoms and combating disease activity in rheumatoid arthritis. Controlled-Trials.com ISRCTN51459023 ISRCTN51459023.
    Full-text · Article · Sep 2013 · PLoS ONE
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    ABSTRACT: Depression is a significant cause of morbidity. Many patients have communicated an interest in non-pharmacological therapies to their general practitioners. Systematic reviews of acupuncture and counselling for depression in primary care have identified limited evidence. The aim of this study was to evaluate acupuncture versus usual care and counselling versus usual care for patients who continue to experience depression in primary care. In a randomised controlled trial, 755 patients with depression (Beck Depression Inventory BDI-II score ≥20) were recruited from 27 primary care practices in the North of England. Patients were randomised to one of three arms using a ratio of 2∶2∶1 to acupuncture (302), counselling (302), and usual care alone (151). The primary outcome was the difference in mean Patient Health Questionnaire (PHQ-9) scores at 3 months with secondary analyses over 12 months follow-up. Analysis was by intention-to-treat. PHQ-9 data were available for 614 patients at 3 months and 572 patients at 12 months. Patients attended a mean of ten sessions for acupuncture and nine sessions for counselling. Compared to usual care, there was a statistically significant reduction in mean PHQ-9 depression scores at 3 months for acupuncture (-2.46, 95% CI -3.72 to -1.21) and counselling (-1.73, 95% CI -3.00 to -0.45), and over 12 months for acupuncture (-1.55, 95% CI -2.41 to -0.70) and counselling (-1.50, 95% CI -2.43 to -0.58). Differences between acupuncture and counselling were not significant. In terms of limitations, the trial was not designed to separate out specific from non-specific effects. No serious treatment-related adverse events were reported. In this randomised controlled trial of acupuncture and counselling for patients presenting with depression, after having consulted their general practitioner in primary care, both interventions were associated with significantly reduced depression at 3 months when compared to usual care alone. Controlled-Trials.com ISRCTN63787732 Please see later in the article for the Editors' Summary.
    Full-text · Article · Sep 2013 · PLoS Medicine
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    Su Golder · Yoon K Loke · Martin Bland
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    ABSTRACT: A diverse range of study designs (e.g. case-control or cohort) are used in the evaluation of adverse effects. We aimed to ascertain whether the risk estimates from meta-analyses of case-control studies differ from that of other study designs. Searches were carried out in 10 databases in addition to reference checking, contacting experts, and handsearching key journals and conference proceedings. Studies were included where a pooled relative measure of an adverse effect (odds ratio or risk ratio) from case-control studies could be directly compared with the pooled estimate for the same adverse effect arising from other types of observational studies. We included 82 meta-analyses. Pooled estimates of harm from the different study designs had 95% confidence intervals that overlapped in 78/82 instances (95%). Of the 23 cases of discrepant findings (significant harm identified in meta-analysis of one type of study design, but not with the other study design), 16 (70%) stemmed from significantly elevated pooled estimates from case-control studies. There was associated evidence of funnel plot asymmetry consistent with higher risk estimates from case-control studies. On average, cohort or cross-sectional studies yielded pooled odds ratios 0.94 (95% CI 0.88-1.00) times lower than that from case-control studies. Empirical evidence from this overview indicates that meta-analysis of case-control studies tend to give slightly higher estimates of harm as compared to meta-analyses of other observational studies. However it is impossible to rule out potential confounding from differences in drug dose, duration and populations when comparing between study designs.
    Full-text · Article · Aug 2013 · PLoS ONE
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    ABSTRACT: Physician gender may be a source of differences in communication between physicians and their patients, which may in turn contribute to patient satisfaction and other outcomes. Our aim was to review systematically research on gender differences in the length, style and content of communication with patients. Seven electronic databases were searched from inception to September 2010 with no language restrictions (included MEDLINE; PsychINFO; EMBASE; CINAHL; Health Management Information Consortium; Web of Science; and ASSIA). 'Grey' literature was also searched. Data extraction and quality assessment was carried out in accordance with Cochrane Collaboration guidelines by at least two reviewers. The review uses mainly narrative synthesis due to the heterogeneous nature of the studies, with only data on consultation length being pooled in a random effects generic inverse variance meta-analysis. Searches yielded 6412 articles, of which 33 studies fulfilled the inclusion criteria. Studies were heterogenous and of mixed quality. Conflicting results are reported for many communication variables. There is some evidence that female physicians adopt a more partnership building style and spend on average 2.24 min longer with patients per consultation (95% CI 0.62-3.86) than their male colleagues. Greater patient engagement by female doctors may reflect a more patient-centred approach, but their longer consultation times will limit the number of consultations they can provide. This has implications for planning and managing services.
    Full-text · Article · Jul 2013 · Journal of Health Services Research & Policy
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    ABSTRACT: We describe methods for meta-analysis of randomised trials where a continuous outcome is of interest, such as blood pressure, recorded at both baseline (pre treatment) and follow-up (post treatment). We used four examples for illustration, covering situations with and without individual participant data (IPD) and with and without baseline imbalance between treatment groups in each trial. Given IPD, meta-analysts can choose to synthesise treatment effect estimates derived using analysis of covariance (ANCOVA), a regression of just final scores, or a regression of the change scores. When there is baseline balance in each trial, treatment effect estimates derived using ANCOVA are more precise and thus preferred. However, we show that meta-analysis results for the summary treatment effect are similar regardless of the approach taken. Thus, without IPD, if trials are balanced, reviewers can happily utilise treatment effect estimates derived from any of the approaches. However, when some trials have baseline imbalance, meta-analysts should use treatment effect estimates derived from ANCOVA, as this adjusts for imbalance and accounts for the correlation between baseline and follow-up; we show that the other approaches can give substantially different meta-analysis results. Without IPD and with unavailable ANCOVA estimates, reviewers should limit meta-analyses to those trials with baseline balance. Trowman's method to adjust for baseline imbalance without IPD performs poorly in our examples and so is not recommended. Finally, we extend the ANCOVA model to estimate the interaction between treatment effect and baseline values and compare options for estimating this interaction given only aggregate data. Copyright
    No preview · Article · Jul 2013 · Statistics in Medicine
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    ABSTRACT: Chronic neck pain is a common condition in the adult population. More research is needed to evaluate interventions aiming to facilitate beneficial long-term change. We propose to evaluate the effect of Alexander Technique lessons and acupuncture in a rigorously conducted pragmatic trial with an embedded qualitative study. We will recruit 500 patients who have been diagnosed with neck pain in primary care, who have continued to experience neck pain for at least three months with 28% minimum cut-off score on the Northwick Park Neck Pain Questionnaire (NPQ). We will exclude patients with serious underlying pathology, prior cervical spine surgery, history of psychosis, rheumatoid arthritis, ankylosing spondylitis, osteoporosis, haemophilia, cancer, HIV or hepatitis, or with alcohol or drug dependency currently or in the last 12 months, or actively pursuing compensation or with pending litigation.The York Trials Unit will randomly allocate participants using a secure computer-based system. We will use block randomisation with allocation to each intervention arm being unambiguously concealed from anyone who might subvert the randomisation process.Participants will be randomised in equal proportions to Alexander Technique lessons, acupuncture or usual care alone. Twenty 30-minute Alexander Technique lessons will be provided by teachers registered with the Society of Teachers of the Alexander Technique and twelve 50-minute sessions of acupuncture will be provided by acupuncturists registered with the British Acupuncture Council. All participants will continue to receive usual GP care.The primary outcome will be the NPQ at 12 months, with the secondary time point at 6 months, and an area-under-curve analysis will include 3, 6 and 12 month time-points. Adverse events will be documented. Potential intervention effect modifiers and mediators to be explored include: self-efficacy, stress management, and the incorporation of practitioner advice about self-care and lifestyle. Qualitative material will be used to address issues of safety, acceptability and factors that impact on longer term outcomes. This study will provide robust evidence on whether there are significant clinical benefits to patients, economic benefits demonstrating value for money, and sufficient levels of acceptability and safety.Trial registration: Current Controlled Trials ISRCTN15186354.
    Full-text · Article · Jul 2013 · Trials

Publication Stats

845 Citations
273.83 Total Impact Points

Institutions

  • 2006-2015
    • The University of York
      • Department of Health Sciences
      York, England, United Kingdom
    • CUNY Graduate Center
      New York, New York, United States
  • 1999-2011
    • St George's, University of London
      Londinium, England, United Kingdom
  • 2010
    • ICL
      Londinium, England, United Kingdom
  • 2000
    • St. George's School
      미들타운, Rhode Island, United States