Bayesian methods for evidence synthesis in cost-effectiveness analysis

Recently, health systems internationally have begun to use cost-effectiveness research as formal inputs into decisions about which interventions and programmes should be funded from collective resources. This process has raised some important methodological questions for this area of research. This paper considers one set of issues related to the synthesis of effectiveness evidence for use in decision-analytic cost-effectiveness (CE) models, namely the need for the synthesis of all sources of available evidence, although these may not 'fit neatly' into a CE model. Commonly encountered problems include the absence of head-to-head trial evidence comparing all options under comparison, the presence of multiple endpoints from trials and different follow-up periods. Full evidence synthesis for CE analysis also needs to consider treatment effects between patient subpopulations and the use of nonrandomised evidence. Bayesian statistical methods represent a valuable set of analytical tools to utilise indirect evidence and can make a powerful contribution to the decision-analytic approach to CE analysis. This paper provides a worked example and a general overview of these methods with particular emphasis on their use in economic evaluation.     

What effects do patients feel from their antihypertensive tablets and how do they react to them? Qualitative analysis of interviews with patients

BACKGROUND: Patients commonly experience palpable effects from antihypertensives. Few studies have examined patients' experiences of these effects and how they influence patients' behaviour and medicine-taking. OBJECTIVES: To describe the palpable effects that patients attribute to their antihypertensive tablets and the ways that they react to them. METHODS: In depth interviews with a maximum variety sample of 38 patients taking antihypertensive medication in 2 mainly urban UK general practices. Qualitative analysis based upon the study's objectives. RESULTS: Most patients attributed palpable effects to their antihypertensives. Some effects were welcome, attributed to lowered blood pressure or a calming effect of tablets, but others were unwelcome. As a result of these, some patients stopped their tablets, but more continued taking tablets as usual, took their tablets in a different way, or countered unwelcome effects by some other means. Although patients discussed stopping tablets with their doctor, they commonly did not discuss other reactions. Patients who accepted persistent unwelcome effects balanced them against reasons to take medication: positive experiences with doctors; perceived benefits of medication; or pragmatic considerations. These reasons overlap with those described previously as balancing patients' reservations about medicines. CONCLUSION: The term 'side effect' fails to distinguish between palpable effects that are welcome or unwelcome, or to recognise that some unwelcome effects may nevertheless be acceptable. If clinicians explore the range of palpable effects that patients attribute to antihypertensives and patients' possible preparedness to tolerate unwelcome effects, they will be better able to identify patients' preferences in this area.     

Innovative learning: employing medical students to write formative assessments

Peninsula Medical School, UK, employed six students to write MCQ items for a formative applied medical knowledge item bank. The students successfully generated 260 quality MCQs in their six-week contracted period. Informal feedback from students and two staff mentors suggests that the exercise provided a very effective learning environment and that students felt they were 'being paid to learn'. Further research is under way to track the progress of the students involved in the exercise, and to formally evaluate the impact on learning.     

Primary paraesophageal hernia in children

Background

Paraesophageal hernias are uncommon in children and are distinctively different from the more common sliding hiatus hernias and those occurring after antireflux surgery in anatomy, pathology, symptoms, complications, and management. We reviewed a single institution's experience with the pathology of paraesophageal hernias.

Methods

We conducted a retrospective analysis of patient records.

Results

Fifty-nine children with paraesophageal hernias were treated during a 42-year period. Their mean age at presentation was 23.4 months (range, 1 day to 11 years). Presenting complaints were recurrent chest infections (n = 32), vomiting (n = 24), symptomatic anemia (n = 20), failure to thrive (n = 18), and dysphagia (n = 6). Five children were asymptomatic, and their diagnosis was established when they were investigated for incidentally noted asymptomatic anemia (n = 3), scoliosis (n = 2), and mumps (n = 1). Radiology typically showed cystic masses in the posterior mediastinum in the right lower chest and occasionally had an air-fluid level in the cystic mass or a dilated esophagus. None presented with strangulation or hematemesis. All patients were operated on. Surgical findings included a peritoneal lined sac and herniation through a widened diaphragmatic hiatus, containing the stomach and at times the transverse colon, spleen, and small bowel. The hernial sac usually occurred on the right. Principles of surgery included reduction of the contents, partial excision of the sac, crural approximation, and a fundoplication in 39 patients. No fundoplication was done in the earlier years in 20 patients, of whom 12 had recurrent reflux symptoms. Postoperative complications were bowel obstruction (n = 6), intussusception (n = 3), dysphagia (n = 3), breakdown of the repair (n = 3), and pneumothorax (n = 1). There was one mortality caused by preoperative aspiration.

Conclusion

Paraesophageal hernias in children are uncommon and most likely caused by a congenital defect. They are associated with considerable morbidity. Strangulation is not a feature. Principles of repair are well established and should include an antireflux procedure.     

British Thoracic Society guidelines for the management of community acquired pneumonia in children: update 2011

The British Thoracic Society first published management guidelines for community acquired pneumonia in children in 2002 and covered available evidence to early 2000. These updated guidelines represent a review of new evidence since then and consensus clinical opinion where evidence was not found. This document incorporates material from the 2002 guidelines and supersedes the previous guideline document.