Specialist care for epilepsy and non-epileptic seizures in adults: methodological issues in the review of multiple socially-complex interventions

Lindsay B, Bradley P

Background: Epilepsy is the most common serious neurological condition after stroke, with a 0.5% prevalence, and a two to three per cent life time risk of being given a diagnosis of epilepsy in the developed world. As a result of perceived deficiencies in the quality of care offered to people with epilepsy, various innovative models to improve epilepsy care have been implemented. Many of these interventions are complex and have not previously been considered in Cochrane reviews. Within this review we identified a wide range of interventions that varied, among other factors, by delivery methods, recipients and media. This variation in intervention design creates issues for analysis within systematic reviews.

Objectives: This presentation aims to identify and discuss the methodological issues resulting from the analysis of multiple socially-complex interventions within a single review.

Methods: We searched in Cochrane Central Register of Controlled Trials (The Cochrane Library, MEDLINE (from January 1966 to date), EMBASE (from 1988), PsycINFO (from 1996) and CINAHL (from 1982). All randomised controlled, controlled or matched trials, cohort or other prospective studies with a control group or time series studies that compare innovative approaches for managing epilepsy with standard care were included in this review. The studies were critically appraised using the Cochrane Effective Practice and Organisation of Care (EPOC) Review Group data collection checklist (2002). Interventions were identified and classified according to a range of parameters.

Results: Fifteen papers reporting on the effectiveness of socially-complex interventions were included in the review. The included articles consisted of 13 randomised controlled trials, 1 controlled clinical trial, 1 controlled before and after trial. No two papers reported on the same intervention. Five distinct intervention types were identifiable. Interventions differed across a series of parameters. Specialist clinics were either doctor-led or nurse-led. Educational programs were either targeted at health professionals or at patients and were delivered using face-to face teaching or through the provision of educational materials. The interventions were delivered in community, primary, secondary and tertiary care settings. The population of patients included in the studies differed in terms of existing co-morbidity, disease severity and time since diagnosis.

Conclusions: Using a broader search strategy to include a range of complex interventions has led to a more comprehensive assessment of innovative service provision for adults with epilepsy. The EPOC checklist proved to be a useful tool in appraising the quality of studies and deciding which studies to include but it does not offer assistance in classifying or appraising the quality of the interventions themselves. More comprehensive inclusion criteria might be used in other Cochrane reviews considering complex interventions. Interestingly, despite these more comprehensive criteria nearly all the included studies were randomised controlled trials. Specialist socially-complex interventions for epilepsy cover a wide spectrum of approaches. The evidence bases for individual interventions are small and inconclusive. However, the clinical heterogeneity of these interventions means that pooling the results of individual studies is problematic. The difficulties associated with the review of evidence about socially-complex interventions need to be addressed in order that systematic reviews can provide more reliable recommendations for future service provision.