Myfawnwy Lloyd Jones

A systematic review, psychometric analysis and qualitative assessment of generic preference-based measures of health in mental health populations and the estimation of mapping functions from widely used specific measures

BACKGROUND Generic preference-based measures of health like the EQ-5D and SF-6D(®) are increasingly being used in economic evaluation and outcome assessment. However, there are concerns as to whether or not these generic measures are appropriate for use in people with mental health problems. OBJECTIVES The EQ-5D and SF-36(®) (including its derivatives the SF-12(®) and SF-6D) were assessed using the psychometric criteria of validity and responsiveness using quantitative and qualitative methods. Another aim was to estimate mapping functions between the EQ-5D and SF-6D and condition-specific measures, where appropriate. DESIGN Four studies were undertaken to examine the appropriateness of the measures: (1) a systematic review of quantitative evidence on validity and responsiveness; (2) a further quantitative assessment of these criteria using existing data sets; (3) a review of qualitative research on the quality of life of people with mental health problems; and (4) qualitative semistructured interviews of people with a full range of problems. A fifth study estimated mapping functions between mental health-specific measures and the EQ-5D and SF-6D. SETTING A choice of venue was offered for the interviews including the participants own home, a room at the university or a centre frequently used by mental health services. PARTICIPANTS The interviews were undertaken with 19 people with a broad range of mental health problems at varying levels of severity. MAIN OUTCOME MEASURES The reviews included the EQ-5D and SF-36 (and the SF-12 and SF-6D). The psychometric analysis included the Hospital Anxiety and Depression Scale (HADS), Clinical Outcomes in Routine Evaluation - Outcome Measure (CORE-OM), Generalised Anxiety Disorder Assessment (GAD-7), General Health Questionnaire (GHQ-12) and Patient Health Questionnaire (PHQ-9). RESULTS (1) and (2) The EQ-5D and SF-36 achieved an adequate level of performance in depression, and to some extent in anxiety and personality disorder. Results from the psychometric analyses in schizophrenia and bipolar disorder have been more mixed. (3) A framework analysis of 13 studies identified six major themes. (4) The interview data fitted the themes from the review well and resulted in minor modifications to the themes. The final set of themes comprised: well-being and ill-being; control, autonomy and choice; self-perception; belonging; activity; hope and hopelessness; and physical health. CONCLUSIONS The EQ-5D and SF-36 achieved mixed results in the quantitative testing against psychometric criteria. The qualitative analysis suggests this is because they provide a very limited coverage of themes identified by people with mental health problems. Recommendations for future work include the development of new preference-based measures in mental health that are based on, or substantially revise, an existing measure. FUNDING The Medical Research Council.

Economic modelling of different treatment strategies for haemophilia A with high-responding inhibitors.

Summary.  This paper reports a systematic review of the cost‐effectiveness of treatment options in patients with haemophilia A with inhibitors. As very little relevant published evidence was identified, an economic modelling exercise was undertaken to calculate the cost‐effectiveness of different strategies in the treatment of high‐responding haemophilia A patients with inhibitors. A decision analysis approach was used to model the expected lifetime clinical outcomes and costs of the more common regimens currently used in UK in treating severe haemophiliacs with inhibitors.

Alteplase for the treatment of acute ischaemic stroke: a single technology appraisal.

This paper presents a summary of the evidence review group report into the clinical effectiveness and cost-effectiveness of alteplase for the treatment of acute ischaemic stroke, in accordance with the licensed indication, based upon the evidence submission from the manufacturer to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The submitted clinical evidence included several randomised controlled trials indicating that, in highly selected patients, alteplase administered at a licensed dose within 3 hours of the onset of acute ischaemic stroke is associated with a statistically significant reduction in the risk of death or dependency at 3 months compared with placebo, despite a significantly increased risk of symptomatic intracranial haemorrhage within the first 7-10 days. Data from the National Institute of Neurological Disorders and Stroke (NINDS) trial suggest that the benefit of treatment is sustained at 6 and 12 months. However, data from observational studies suggest that few patients with acute ischaemic stroke will be eligible for alteplase therapy under the terms of the current licensing agreement. In particular, many patients will be excluded by virtue of their age, and many more by the restriction of therapy to patients in whom treatment can be initiated within 3 hours of symptom onset. The manufacturers submission included a state transition model evaluating the impact of treatment with alteplase within 3 hours of onset of stroke symptoms compared to standard treatment reporting that, in the base-case analysis, alteplase was both less costly and more effective than standard treatment. This increased to a maximum of approximately 4000 pounds upon one-way sensitivity analysis of the parameters. The probabilistic sensitivity analysis presented within the submission suggests that the probability that alteplase has a cost-effectiveness ratio greater than 20,000 pounds per quality-adjusted life-year (QALY) gained is close to 1 (0.99). The results of the short-term model demonstrate that alteplase is cost-effective over a 12-month period, with an incremental cost-effectiveness ratio of 14,026 pounds per QALY gained. This increased to a maximum of 50,000 pounds upon one-way sensitivity analysis of the parameters. At 12 months, the probabilistic sensitivity analysis presented within the submission suggests that the probability that alteplase has a cost-effectiveness ratio greater than 20,000 pounds per QALY gained is approximately 0.7. The guidance issued by NICE in April 2007 as a result of the STA states that alteplase is recommended for the treatment of acute ischaemic stroke only when used by physicians trained and experienced in the management of acute stroke and in centres with the required facilities.