Unsolved issues of mixed treatment comparison meta-analysis: network size and inconsistency

2012 ◽  
Vol 3 (4) ◽  
pp. 300-311 ◽  
Author(s):  
Sibylle Sturtz ◽  
Ralf Bender
2016 ◽  
Vol 4 (13) ◽  
pp. 1-304 ◽  
Author(s):  
Nicky Cullum ◽  
Hannah Buckley ◽  
Jo Dumville ◽  
Jill Hall ◽  
Karen Lamb ◽  
...  

BackgroundComplex wounds are those that heal by secondary intention and include lower-limb ulcers, pressure ulcers and some surgical wounds. The care of people with complex wounds is costly, with care mainly being delivered by community nurses. There is a lack of current, high-quality data regarding the numbers and types of people affected, care received and outcomes achieved.ObjectivesTo (1) assess how high-quality data about complex wounds can be captured effectively for use in both service planning and research while ensuring integration with current clinical data collection systems and minimal impact on staff time; (2) investigate whether or not a clinical register of people with complex wounds could give valid estimates of treatment effects, thus reducing dependence on large-scale randomised controlled trials (RCTs); (3) identify the most important research questions and outcomes for people with complex wounds from the perspectives of patients, carers and health-care professionals; (4) evaluate the potential contributions to decision-making of individual patient data meta-analysis and mixed treatment comparison meta-analysis; and (5) complete and update systematic reviews in topic areas of high priority.MethodsTo meet objectives 1 and 2 we conducted a prevalence survey and developed and piloted a longitudinal disease register. A consultative, deliberative method and in-depth interviews were undertaken to address objective 3. To address objectives 4 and 5 we conducted systematic reviews including mixed treatment comparison meta-analysis.ResultsFrom the prevalence survey we estimated the point prevalence of all complex wounds to be 1.47 per 1000 people (95% confidence interval 1.38 to 1.56 per 1000 people). Pressure ulcers and venous leg ulcers were the most common type of complex wound. A total of 195 people with a complex wound were recruited to a complex wounds register pilot. We established the feasibility of correctly identifying, extracting and transferring routine NHS data into the register; however, participant recruitment, data collection and tracking individual wounds in people with multiple wounds were challenging. Most patients and health professionals regarded healing of the wound as the primary treatment goal. Patients were greatly troubled by the social consequences of having a complex wound. Complex wounds are frequently a consequence of, and are themselves, a long-term condition but treatment is usually focused on healing the wound. Consultative, deliberative research agenda setting on pressure ulcer prevention and treatment with patients, carers and clinicians yielded 960 treatment uncertainties and a top 12 list of research priorities. Of 167 RCTs of complex wound treatments in a systematic review of study quality, 41% did not specify a primary outcome and the overall quality of the conduct and reporting of the research was poor. Mixed-treatment comparison meta-analysis in areas of high priority identified that matrix hydrocolloid dressings had the highest probability (70%) of being the most effective dressing for diabetic foot ulcers, whereas a hyaluronan fleece dressing had the highest probability (35%) of being the most effective dressing for venous ulcers; however, the quality of this evidence was low and uncertainty is high.ConclusionsComplex wounds are common and costly with a poor evidence base for many frequent clinical decisions. There is little routine clinical data collection in community nursing. A prospective complex wounds register has the potential to both assist clinical decision-making and provide important research evidence but would be challenging to implement without investment in information technology in NHS community services. Future work should focus on developing insights into typical wound healing trajectories, identifying factors that are prognostic for healing and assessing the cost-effectiveness of selected wound treatments.FundingThe National Institute for Health Research Programme Grants for Applied Research programme.


2018 ◽  
Vol 52 (12) ◽  
pp. 1182-1194 ◽  
Author(s):  
Jack J. Chen ◽  
Yi Han ◽  
Jonathan Tang ◽  
Ivan Portillo ◽  
Robert A. Hauser ◽  
...  

Background: The comparative effects of droxidopa and midodrine on standing systolic blood pressure (sSBP) and risk of supine hypertension in patients with neurogenic orthostatic hypotension (NOH) are unknown. Objective: To perform a Bayesian mixed-treatment comparison meta-analysis of droxidopa and midodrine in the treatment of NOH. Methods: The PubMed, CENTRAL, and EMBASE databases were searched up to November 16, 2016. Study selection consisted of randomized trials comparing droxidopa or midodrine with placebo and reporting on changes in sSBP and supine hypertension events. Data were pooled to perform a comparison among interventions in a Bayesian fixed-effects model using vague priors and Markov chain Monte Carlo simulation with Gibbs sampling, calculating pooled mean changes in sSBP and risk ratios (RRs) for supine hypertension with associated 95% credible intervals (CrIs). Results: Six studies (4 administering droxidopa and 2 administering midodrine) enrolling a total of 783 patients were included for analysis. The mean change from baseline in sSBP was significantly greater for both drugs when compared with placebo (droxidopa 6.2 mm Hg [95% CrI = 2.4-10] and midodrine 17 mm Hg [95% CrI = 11.4-23]). Comparative analysis revealed a significant credible difference between droxidopa and midodrine. The RR for supine hypertension was significantly greater for midodrine, but not droxidopa, when compared with placebo (droxidopa RR = 1.4 [95% CrI = 0.7-2.7] and midodrine RR = 5.1 [95% CrI = 1.6-24]). Conclusion and Relevance: In patients with NOH, both droxidopa and midodrine significantly increase sSBP, the latter to a greater extent. However, midodrine, but not droxidopa, significantly increases risk of supine hypertension.


2013 ◽  
Vol 166 (2) ◽  
pp. 431-439 ◽  
Author(s):  
Rodrigo Antonini Ribeiro ◽  
Patricia Klarmann Ziegelmann ◽  
Bruce Bartholow Duncan ◽  
Steffan Frosi Stella ◽  
José Luiz da Costa Vieira ◽  
...  

2012 ◽  
Vol 46 (11) ◽  
pp. 1491-1505 ◽  
Author(s):  
Rishi J Desai ◽  
Richard A Hansen ◽  
Jaya K Rao ◽  
Tania M Wilkins ◽  
Elizabeth A Harden ◽  
...  

BACKGROUND: Introduction of biologic disease-modifying antirheumatic drugs (DMARDs) has considerably changed treatment options for rheumatoid arthritis (RA) over the past decade. Very little information is available on comparative discontinuation rates of the biologics. OBJECTIVE: To compare treatment discontinuations for 9 biologic DMARDs in adults with RA. METHODS: We searched electronic databases through May 2012 to retrieve randomized controlled trials (RCTs) of patients with RA that compared biologic DMARDs with placebo or another biologic DMARD. The primary outcome was treatment discontinuation during the blinded phase of the trials, measured as overall withdrawals, withdrawals resulting from lack of efficacy, and withdrawals resulting from adverse events. Random-effects meta-analysis estimated the effect size for individual agents, and adjusted indirect comparisons were made between biologics using mixed treatment comparisons (MTC) meta-analysis. RESULTS: Forty-four trials were included in the analysis. In comparison with placebo, biologics were less likely to be withdrawn because of lack of efficacy (OR 0.22, 95% CI 0.17 to 0.27) and more likely to be withdrawn because of an adverse event (OR 1.41, 95% CI 1.16 to 1.70). Based on the MTC, certolizumab had the most favorable overall withdrawal profile, followed by etanercept and rituximab. Certolizumab had lower relative withdrawal rates resulting from lack of efficacy than adalimumab, anakinra, and infliximab. Anakinra had higher relative withdrawal rates resulting from lack of efficacy than most other biologics. Certolizumab and infliximab had more, while etanercept had fewer, withdrawals because of adverse events than most other drugs. CONCLUSIONS: Based on MTC using data from RCTs, differences in discontinuation rates were observed, generally favoring certolizumab, etanercept, and rituximab over other biologic DMARDs. These potential differences need to be further explored in head-to-head trials or well-conducted observational studies.


2012 ◽  
Vol 3 (3) ◽  
pp. 255-255 ◽  
Author(s):  
Guobing Lu ◽  
Nicky J. Welton ◽  
Julian P. T. Higgins ◽  
Ian R. White ◽  
A. E. Ades

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