Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial

The EuroQol Group first met in 1987 to test the feasibility of jointly developing a standardised non-disease-specific instrument for describing and valuing health-related quality of life. From the outset the Group has been multi-country, multi-centre, and multi-disciplinary. The EuroQol instrument is intended to complement other forms of quality of life measures, and it has been purposefully developed to generate a cardinal index of health, thus giving it considerable potential for use in economic evaluation. Considerable effort has been invested by the Group in the development and valuation aspects of health status measurement. Earlier work was reported upon in 1990; this paper is a second 'corporate' effort detailing subsequent developments. The concepts underlying the EuroQol framework are explored with particular reference to the generic nature of the instrument. The valuation task is reviewed and some evidence on the methodological requirements for measurement is presented. A number of special issues of considerable interest and concern to the Group are discussed: the modelling of data, the duration of health states and the problems surrounding the state 'dead'. An outline of some of the applications of the EuroQol instrument is presented and a brief commentary on the Group's ongoing programme of work concludes the paper.

A multitude of factors including biochemical, genetic, and acquired abnormalities may contribute to osteoarthritis of the hip. Although the pathomechanism of degenerative process affecting the dysplastic hip is well understood, the exact pathogenesis for idiopathic osteoarthritis has not been established. Based on clinical experience, with more than 600 surgical dislocations of the hip, allowing in situ inspection of the damage pattern and the dynamic proof of its origin, we propose femoroacetabular impingement as a mechanism for the development of early osteoarthritis for most nondysplastic hips. The concept focuses more on motion than on axial loading of the hip. Distinct clinical, radiographic, and intraoperative parameters can be used to confirm the diagnosis of this entity with timely delivery of treatment. Surgical treatment of femoroacetabular impingement focuses on improving the clearance for hip motion and alleviation of femoral abutment against the acetabular rim. It is proposed that early surgical intervention for treatment of femoroacetabular impingement, besides providing relief of symptoms, may decelerate the progression of the degenerative process for this group of young patients.

The SF-12 is a multidimensional generic measure of health-related quality of life. It has become widely used in clinical trials and routine outcome assessment because of its brevity and psychometric performance, but it cannot be used in economic evaluation in its current form. We sought to derive a preference-based measure of health from the SF-12 for use in economic evaluation and to compare it with the original SF-36 preference-based index. The SF-12 was revised into a 6-dimensional health state classification (SF-6D [SF-12]) based on an item selection process designed to ensure the minimum loss of descriptive information. A sample of 241 states defined by the SF-6D (of 7500) have been valued by a representative sample of 611 members of the UK general population using the standard gamble (SG) technique. Models are estimated of the relationship between the SF-6D (SF-12) and SG values and evaluated in terms of their coefficients, overall fit, and the ability to predict SG values for all health states. The models have produced significant coefficients for levels of the SF-6D (SF-12), which are robust across model specification. The coefficients are similar to those of the SF-36 version and achieve similar levels of fit. There are concerns with some inconsistent estimates and these have been merged to produce the final recommended model. As for the SF-36 model, there is evidence of over prediction of the value of the poorest health states. The SF-12 index provides a useful tool for researchers and policy makers wishing to assess the cost-effectiveness of interventions.