Jennifer O’Donnell

Protocol for a systematic review of the diagnostic and prognostic utility of tests currently available for the detection of aspirin resistance in patients with established cardiovascular or cerebrovascular disease

BackgroundThe benefits of aspirin as an anti-platelet agent are well established; however, there has been much debate about the lack of uniformity in the efficacy of aspirin to inhibit platelet function. In some patients, aspirin fails to inhibit platelets even where compliance has been verified, a phenomenon which has been termed “aspirin resistance”. These patients may in turn be at a higher risk of future vascular events. The proportion of “resistant” patients identified depends on the type of platelet function test. Therefore, the aim of this systematic review is to determine which, if any, platelet function test has utility in terms of identifying patients with a high risk of vascular events. The review has been registered with PROSPERO (CRD42012002151).MethodsRelevant studies will be sought from bibliographic databases. Trials registers will be searched for ongoing studies. Reference lists will be checked and subject experts contacted. There will be no date or language restrictions. Standard reviewing methodology to minimise bias will be employed. Any prospective studies in patients on aspirin therapy and assessing platelet function in relation to relevant clinical outcomes will be included, as will studies reporting prognostic models. Risk of bias assessment will be based on the Quality Assessment of Diagnostic Accuracy Studies guidelines, and suitable criteria for assessing quality of prognostic studies. Data on test accuracy measures, relative risks, odds or hazard ratios will be extracted and meta-analysed, where possible, using a random-effects model to account for between-study heterogeneity. Where appropriate, the causes of heterogeneity will be explored through meta-regression and sub-group or sensitivity analyses. If platelet function testing is demonstrated to have diagnostic/predictive utility in a specific population, the potential for a cost-effectiveness analysis will be considered and, if possible, an economic model constructed. This will be supported by a systematic review of existing economic evaluation studies.DiscussionThe results of the review could indicate if platelet function test(s) could lead to a reliable prediction of the risk of clinically important events in a defined population, and thus support investigations into adjustments to therapy in order to compensate for a predicted poor response to standard aspirin.

General practice views of managing childhood obesity in primary care: a qualitative analysis:

Objective To explore general practice staff views of managing childhood obesity in primary care. Design A qualitative study to elicit the views of clinical and non-clinical general practice staff on managing childhood obesity. Setting Interviews were conducted at 30 general practices across England. These practices were interviewed as part of the Quality and Outcomes Framework Pilot Study. Participants A total of 52 staff from 30 practices took part in a semi-structured interview. Main outcome measures Key themes were identified through thematic analysis of transcripts using an inductive approach. Results Three themes were identified: lack of contact with well children, sensitivity of the issue, and the potential impact of general practice. Identifying overweight children was challenging because well children rarely attended the practice. Interviewees felt ill equipped to solve the issue because they lacked influence over the environmental, economic and lifestyle factors underpinning obesity. They described little evidence to support general practice intervention and seemed unaware of other services. Raising the issue was described as sensitive. Conclusion General practice staff were unconvinced that they could have a significant role in managing childhood obesity on a large scale. Participants believed schools have more contact with children and should coordinate the identification and management of overweight children. Future policy could recommend a minor role for general practice involving opportunistically identifying overweight children and signposting to obesity services.