EBM – AQuAS Blog

Scientific evidence and clinical practice: the case of hip prostheses in Catalonia

9 Mar

A total hip replacement is one of the surgical procedures which provide greatest satisfaction among patients due to the significant improvement in the quality of life they experience.

So much so, that it has been defined by some authors as the surgery of the 20th Century. It is a procedure which consists in substituting the hip joint with an artificial joint or prosthesis.

The most common reason for surgical intervention is arthrosis, a disease caused by the wear-and-tear of the cartilage which leads to a malfunction of the joint. It is especially common in older people, older than 65, who live with pain and which can limit their day-to-day activities considerably.

In today’s context of continuous technological innovations and advances and facing the enormous pressure from manufacturers, the range of prosthesis available to orthopaedic surgeons is wider than ever. This situation demands that the prostheses used have supporting scientific evidence based on clinical studies or on data from arthroplasty registries.

The legislation which regulates the commercialisation of medical devices, such as prostheses, is more lax than that which regulates drugs which means that not the same type of studies are required for their approval and in consequence, neither is the scientific evidence. In fact, this precise legislation is undergoing a review at present and a new one on this matter will soon be made available.

Several years ago, the prestigious journal BMJ (British Medical Journal) published an article in which it was highlighted that in the UK, 24% of hip prostheses used had no scientific evidence to demonstrate their clinical effectiveness.

As a consequence of that publication and applying the same methodology, at the Hospital Sant Rafael and in collaboration with the Catalan Arthroplasty Registry (RACat) of the Agency for Health Quality and Assessment of Catalonia (AQuAS), we embarked on the task of analysing what the scientific evidence was on hip prostheses used in public hospitals in Catalonia which had sent their data in to the RACat during the period 2005-2013.

We did this via a search on different platforms putting the spotlight on Orthopaedic Data Evaluation Panel (ODEP), as well as Tripdatabase, PubMed and Google acadèmic.

Following the analysis of the 18,816 acetabular or hip cups and 19,546 femoral stems (the main components of the hip prosthesis) collected in the registry, our first surprise was to observe that 123 different models of cups had been used and 138 different models of stems. In the group of participating hospitals in the RACat during the period of the study, it was seen that with many of these models less than 10 units in number of each had been used.

As these models only represent 1% of implants used, they were excluded from the study and in the end 74 models of hip cups and 75 models of femoral stems were studied.

Artroplàsties PTM

The results of the analysis, either recently published or not yet published, now at a pre-publication stage, show that less than 50% of components used had the highest level of scientific evidence in accordance with the ODEP. This top level is achieved when there are studies having 10 years at least of monitoring with a number of prostheses evaluated exceeding 500 units.

What also caught our attention was not finding any evidence for 18 hip cups or 16 femoral stems which represented, respectively, 13.56% and 9.53% of all implants carried out during this period.

Artroplàsties -taula

All scientific studies show limitations and it is not always possible to offer exhaustive results. Aware of this, and of the fact that the data in our study are the results of a research project which might not be able to reflect what the reality of public hospitals in Catalonia is in absolute terms.

We do want to stress that the task of the orthopaedic surgeon needs to be more and more regulated by evidence based medicine and this is, precisely, one of main purposes of arthroplasty registers: to carry out studies like the one we have been able to do at Hospital Sant Rafael with the aim of improving the health care of people.

Post written by Miquel Pons, Danieol Chaverri and Luis Lobo, Hospital Sant Rafael, Barcelona.

Broadening perspectives in health service assessment

8 Sep

What lies behind a significant volume of hospital readmissions? What makes a service present a good healthcare praxis? What obstacles are there when changing to a healthcare model such as in major out-patient surgery which encourages patients to go home on the same day as their operation? Do managers and nursing staff have the same opinion about what efficiency is in an operating theatre? What is the perception of professionals of the possible benefits of people-centred attention?

Do we all see a dragon?

Drac

Reality is complex and therefore approaches are needed which facilitate the interpretation and understanding of that reality. With qualitative research, places can be reached otherwise unattainable when using other methodological aproximations. When answering questions like those we asked ourselves previously, a truly qualitative approach is required. We need to make the approach using an adequate and credible technique to validate the process of all those involved and to ensure precision in results as is done in quantitative research but not forgetting that we need to be critical and independent in the analysis made.

We will briefly outline the evolution of the qualitative approaches in the context of the assessment of health services. A reflection on the usefulness of qualitative techniques in the assessment of health services or medical technologies is not a new one and you can find a series on this subject in the British Medical Journal of 1995 and in the Health Technology Assessment report of 1998.

bmj-1995-eng

Health assessment agencies have given great importance to questions about the scientific evidence available when talking about the efficiency and safety of treatments and biomedical interventions of a clinical nature. Randomized controlled trials and systematic reviews are considered to be the reference standards for causal atributions of the benefits of an intervention for the improvement in the health status of patients.

Society has evolved and the needs of the system adapt to this. We formulate new questions related to the preferences and expectations of users facing treatment and how different professionals contribute to providing better results in patient health care. One must bear in mind that when assessing the benefits and results of attention given, many factors come into play.

In this context, the paradigm of evidence based medicine and the supposed superiority of quantitative approaches and of some study designs above others, have created obstacles in the application of qualitative research. In this sense, the letter to the editors of the British Medical Journal signed by more than 70 researchers of reference for giving their support to qualitative research is clear proof of this remaining obstacle.

bmj-2016-eng

Questioning the efficacy of a medical drug cannot be answered using a qualitative approach but we can broaden the scope of questions that we pose ourselves.

For example, we can consider asking ourselves questions, among others, about the preferences of patients, the perception of the benefits of a medical drug, the expectations or opinion of professionals that prescribe it or the possible reasons for a low adherence of the medical drug.

Another scenario could be that of a patient with osteoarthritis who has undergone a knee replacement (arthroplasty) and who is being attended by several professionals such as the primary care doctor, the traumatologist surgeon, the anaesthetist, the nurse, the physiotherapist and other professionals if the patient has other comorbidities. That patient has certain preferences and expectations which need to be understood and then give the health care to cover those needs, which can go beyond the mere surgical procedure.

With qualitative research we develop a discourse, texts, opinions and perceptions of people, communities, with images, perspectives, ideologies and complexities. We must guarantee rigour and that the photograph and interpretation of reality that we make remain valid and coherent for the research group and the populaton or group of people that we are assessing.

The application of qualitative techniques has been on the rise using interviews, semi-structured questionnaires, field notes, focus or discussion groups to gather the opinion of different groups of professionals and users.

From my point of view, there are three examples which can be of great use to know the approach and the process in carrying out an assessment of services with a qualitative approach:

Avoiding the classic metrics means being able to measure in an alternative or complementary way by combining different approaches be they qualitative or quantitative. I find the introduction to qualitative research we find in René Brown’s TED talk the power of vulnerability. This qualitative researcher recommends we measure that which is apparently unmeasurable and go more in depth into the complex phenomenon of vulnerabilty.

We broaden perspectives by understanding the reality from within, by bearing in mind the multiple existing points of view to improve that which is disfunctional or by identifying better practices to spread them. We can measure what we want to measure. It will be necessary to adapt the approach to the context and audiences and to continue progressing to show with rigour and practice the usefulness of qualitative approaches.

We continue learning. This time, it has been at the Congrés Iberoamericà de Recerca Qualitativa en Salut (in Twitter #IICS2016) held in Barcelona, 5-7 September. The Agència de Qualitat i Avaluació Sanitàries de Catalunya (AQuAS) and the Agència de Salut Pública de Catalunya (ASPCAT) shared the stand to explain their experiences.

2016 Congreso Iberoamericano de Investigación Cualitativa en Salud — Santi Gómez Santos (AQuAS/ASPCAT), Dolors Rodríguez Arjona (ASPCAT), Mireia Espallargues (AQuAS), Vicky Serra-Sutton (AQuAS)

Post written by Vicky Serra-Sutton (@vserrasutton), sociologist PhD in AQuAS.