Clinical Guidelines / Guidelines
Clinical practice guidelines have undergone a huge transformation during the last decade, due to the exhaustive search of data in the literature and systematization in the evaluation phase of said data and formulas for the establishment of conclusions. The 2 fundamental aspects on which the clinical guidelines are currently based are:
- The quality of the evidence.
- The strength of the recommendations.
Both criteria respond to a classification from higher to lower validity:
Degree of scientific quality of the recommendation:
- 1a. Scientific data from meta-analyzes of randomized trials.
- 1b. Scientific data from at least one randomized trial.
- 2a. Scientific data from a well-designed controlled study without randomization.
- 2b. Scientific data from at least one well-designed quasiexperimental study of another type.
- 3. Scientific data from well-designed non-experimental studies, such as comparative studies, correlation studies and clinical cases.
- 4. Scientific data from reports or opinions of expert committees or from the clinical experience of authorities in the field.
Strength of recommendation:
- A. Based on clinical studies of good quality and consistency in which specific recommendations are addressed and include at least one randomized trial.
- B. Based on well-conducted clinical studies, but without randomized clinical trials.
- C. Issued despite the absence of directly applicable good quality clinical trials.
The search, ordering and scoring of the published data allows locating the most reliable evidence for each concept (for example: what functional benefit has been obtained for each surgical treatment against prostate cancer), establishing levels of evidence quality (for each data item) or group of data) depending on the consistency of the observations (meta-analyzes and randomized trials are the best sources). Once the best evidence is gathered, it is possible to establish recommendations, which will be stronger and more consistent the higher the quality of the evidence on which they are based (for example: Recommend or not radical prostatectomy versus other treatment modalities of prostate cancer ).
A good guide has to fulfill a series of premises:
- Valid: providing the best available evidence.
- Reliable: that users trust it.
- Reproducible: that can be applied by different doctors to the same disease.
- Flexible: medicine is not an exact science and therefore recommendations can contemplate different alternatives.
When recommendations are made, the group developing a guide should clearly state the benefit resulting from following a given recommendation. With quality evidence it is possible to establish convincing recommendations. The stages of data collection, establishment of evidence (with its degree of quality) and development of recommendations (with their degree of strength) are the most critical in the process of developing a clinical guide.
According to the instruments of the AGREE (Appraisal of Guidelines Research and Evaluation), the stage of formulating recommendations, must be supported by a rigorous mark in the elaboration, contemplating the following aspects: the explicit methodology, the establishment of clinical objectives defined, the relationship between benefits and risks for each option based on criteria of scientific evidence. For the SIGN (Scotish Intercollegiate Guidelines Network), one of the most important entities in the world dedicated to the development of clinical practice guidelines, which has a highly developed logistics structure, the preparation of the different guidelines takes place within a scheme in the one that involves multiple agents (clerks, engineers, publicists, nurses, epidemiologists, clinicians). They propose a categorization on the quality of the evidence and the strength of the recommendation.
The guidelines of the European Association of Urology have been translated into Spanish on the initiative of the Spanish Association of Urology and are freely available to all Spanish-speaking urologists.