Open Journal Systems

CLINICAL PRACTICE GUIDELINES

Received: November 28^th 2014

Accepted: December 16^th 2014

Methodology for the development and update of practice guidelines: current state

Antonio Barrera-Cruz,^a Arturo Viniegra-Osorio,^a Adriana Abigail Valenzuela-Flores,^a Laura del Pilar Torres-Arreola,^a Javier Dávila-Torres^a

^aCoordinación Técnica de Excelencia Clínica, Instituto Mexicano del Seguro Social, Distrito Federal, México

Communication with: Laura del Pilar Torres-Arreola

Thelephone: (55) 5584 5134

Email: lauratorresster@gmail.com

The current scenario of health services in Mexico reveals as a priority the implementation of strategies that allow us to better respond to the needs and expectations of individuals and society as a whole, through the provision of efficient and effective alternatives for the prevention, diagnosis and treatment of diseases. In this context, clinical practice guidelines constitute an element of management in the health care system, whose objective is to establish a national bechmark for encouraging clinical and management decision making, based on recommendations from the best available evidence, in order to contribute to the quality and effectiveness of health care. The purpose of this document is to show the methodology used for the development and updating of clinical practice guidelines that the Instituto Mexicano del Seguro Social has developed in line with the sectorial model in order to serve the user of these guidelines.

Keywords: Development and update; Health planning; Strategies; Practice guidelines as topic.

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The current scenario of health services in Mexico reveals as a priority the implementation of strategies that allow us to better respond to the needs and expectations of individuals and society as a whole, through the provision of efficient and effective alternatives for the prevention, diagnosis, and treatment of diseases. In this context, clinical practice guidelines constitute an element of management in the health care system, whose objective is to establish a national benchmark for encouraging clinical and management decision making, based on recommendations from the best available evidence, in order to contribute to the quality and effectiveness of health care.

In our country, the Sistema Nacional de Salud has made significant advances that have been reflected in a strengthening of the coverage of health services, a reduction in the rate of infant mortality, and increased life expectancy of the population. However, challenges remain to be overcome, including facilitating access to health services and providing effective comprehensive care with quality, warmth, and security for the benefit of the patient and their family.

The Strategic Project for the Development, Implementation, and Evaluation of CPGs was designed in the Instituto Mexicano del Seguro Social (IMSS) to contribute to the updating of medical practice and the development of CPGs, with the identification of best practices and the efficient use of resources for health, so that the integrated action of the three levels of care can be located, to implement the project transversely to all disciplines involved in the care of the most common and urgent ailments.^1,2

On the other hand, it should be noted that in the Institute, as part of CPG dissemination, implementation, and evaluation activities done in medical units throughout the country, the clinical practice guidelines and care protocols are used to provide clinical care (QPS.2.1 quality and patient safety, in our context adapted as Quality and Patient Safety Improvement),³ in accordance with the hospital certification standards, specifically the standards focusing on QPS management for the purpose of helping the standardization process of care, risk reduction, efficient resource use, providing timely and effective care, by implementing at least one guide, guideline, or clinical path per year using a methodological process.

Clinical rationale

Health professionals must daily make multiple and complex care decisions in which they wield the ability to identify the most suitable alternative by assessing the implications in terms of clinical outcomes, appropriateness, risks, costs, and social and individual impact.

The complexity of this decision process is exacerbated by the increased care opportunities and options arising from the advancement of scientific knowledge, the inability to assimilate all available scientific information, and the rationalization of health resources, altogether with the variability of clinical practice styles.⁴

CPGs are "informational documents including recommendations to optimize patient care, based on a systematic review of the evidence and the evaluation of the benefits and harms of different options in health care".⁵

The fundamental intention with the development of CPGs is to optimize health care to identify the most effective options for patient care in order to harmonize clinical decisions.^6,7 Their quality and usefulness have been positively correlated with the productivity of the group that produces them.^8,9

Appropriately developing CPGs involves making sure that they are valid, reproducible, reliable, applicable, and clear, besides being developed by an interdisciplinary group involved in all stages of the process.^10,11

The purpose of this document is to show, in line with the sector model, the methodology used for the development and updating of CPGs developed by IMSS, so this document will serve the guide user as a starting point to understand and support of their use.

Methods

For the development and updating of CPGs, a mixed adaptation-adoption methodology was used in topics where the CPGs published by recognized international organizations responded to questions and covered the quality criteria defined by the instrument Appraisal of Guidelines Research and Evaluation II (AGREE II) (Table I).¹²

Adapting a guide has been defined as the systematic method by which changes are made to the recommendations to suit the context in which the guide is to be used. Adapting a high quality CPG aims to take advantage of an existing guide in order to make the development efficient without undermining the validity of the resulting recommendations. The adaptation of a CPG is an alternative for the development of guidelines to respond to a need in each context; this way, we make sure to reduce the duplication of effort, in addition to making the creation process more efficient and possibly an element that promotes adherence to the recommendations.^13,14

The adaptation process is based on the following grounds:

• Respect the principles of evidence-based medicine for the development of the guide.
• Use a reliable and consistent methodology to ensure the quality of the guide adapted.
• Encourage the participation of all future users to encourage acceptance and appropriation of the guide adapted.
• Explicitly consider the context in which the guide will be used to ensure use in local practice.
• Report transparently how the guide was adapted to promote confidence in the recommendations made using it.
• Use a flexible format that suits the specific needs and circumstances of where the guide will be used.
• Report on the guide’s adaptation to the authors of the guide to be used as the basis for adaptation.

Stages for CPG development

The first step in CPG development is to identify the need for its construction, given the magnitude of the problem and variability in clinical practice, as well as costs of care. At this stage the working group is formed with clinical experts and methodologists necessary for the CPG’s development. After forming the group, a work plan is defined for each member of the team, including the development of the CPG under techniques systematized by consensus, clinical questions to be answered by the guide, giving priority to issues that have variability in clinical practice, aspects of direct impact on morbidity, new techniques and treatments, and what was considered improvable in patient care. Algorithm 1 shows the main elements to be considered in the process of CPG adaptation or development.

Structured clinical questions

In daily practice, the need for information for decision making is a fundamental aspect that requires formulating correctly (in the form of questions) our clinical questions, and using complete sources of information effectively and efficiently. This process is facilitated by the practice of evidence-based medicine (EBM), which has been defined by Sackett¹⁵ as "the conscientious, explicit, and judicious use of the best current evidence in making decisions about patient care". This is a methodology of critical analysis and study of the scientific literature that gives value to both clinical experience and the certainty of information on the health care of people.

The convert the need for information into a structured clinical question, one must be aware of what is known and what is not known, as well as the knowledge that needs to be initiated, updated, or reinforced. In other words, we need to identify information needs. Without any doubt, structured clinical questions and the correct development of clinical recommendations are two of the pillars of this process.

Type of questions

Clinical questions can be classified by their character as general, specific, and by their nature as: etiology, prevention, diagnosis, treatment, and prognosis.

General or basic questions, with appropriate formal structure, generally have two essential components:

1. The interrogative particle (who, what, where, when, how, why), followed by a verb.
2. The condition or an aspect of it. Examples of this kind of questions are: What is the most common etiologic agent of bacterial pneumonia in children? What is type 2 diabetes mellitus? How is lupus nephritis diagnosed?

In other circumstances, our question may be greater and may affect the decision-making process in a particular patient. This is the case of specific questions also known as "first line," which require the person formulating them to have prior knowledge, as they are more complex and require a structure, as will be detailed later.^16,17

Another way to classify the type of questions more directly related to the specific clinical situation is by dividing them into two groups:¹⁸

• Preparation Questions (background): these are part of the general knowledge of a condition. They are usually answered in textbooks and review articles (narrative review). They regard aspects related to the nature of the condition, treatment, and common diagnostic methods for a disease (e.g. What are the treatment options for adults for community-acquired pneumonia? What are the diagnostic methods for assessing acute abdomen in women of childbearing age?).
• Action Questions (foreground): these are specific questions we ask to make clinical decisions in different areas, for example, about the effects of therapies, regarding the accuracy or impact of diagnostic methods, or in connection with observations on the cause of some disease. These questions form the basis for the practice of evidence-based medicine and could only be answered using the results of clinical studies that have been done in patient groups with the same characteristics and similar problems. As a physician advances in their practice of the profession, the proportion of preparation and action questions that arise changes. Thus, initially most of the questions are preparation, and very few are action, while more specific questions or action questions arise as the doctor gains experience and knowledge. Importantly, despite having vast clinical experience and extensive knowledge, they never stop generating preparation questions.

Transforming information needs into a structured clinical question (PICO format: patient, intervention, comparison, outcome) and dividing it into its components allows one to plan the most efficient search strategy by facilitating the process of choosing key terms to be used in the search. Selecting words from the first two components of the question reveals relevant articles in most cases.¹⁹

The structured clinical question is made up of three or four components:

1. Patient: age group, stage of disease, comorbidity, etc.
2. Intervention: prognostic factor, etiologic agent, diagnostic test, intervention, etc.
3. Comparison: this refers to the alternative to the intervention under study, such as the standard treatment or placebo, the absence of a risk factor, the absence of etiologic agent, the gold standard, or reference to a diagnostic test, etc.
4. Outcomes: these are clinically important outcome variables in the case of studies on efficacy, prognosis, or etiology, and estimates of performance or diagnostic accuracy (sensitivity, specificity, likelihood ratios, and predictive values) in the case studies’ diagnostic tests.

The advantage of formulating specific clinical questions with the PICO format is unambiguously defining what one wants to know and helping to do the literature search, because there is a type of study design able to answer each type of question.

Updating CPGs

Progress in scientific knowledge and its constant evolution, and the emergence of new studies and results regarding best practices make it necessary for CPG to be subjected to a renewal process in order to maintain the validity and quality of its recommendations.

Updating a CPG is understood as a process that aims to maintain the validity of the recommendations made therein. Studies mention that the deadline for considering a CPG obsolete is three to five years, so the update should be done after that period. However, in some cases the update can be made before the end of the time limit.

Despite its usefulness, the lifetime of the CPG is limited due to the rapid advancement of clinical evidence on which recommendations are based. The emergence of new evidence after its production can make the recommendations weak when a critical and reflective analysis of the available scientific literature was not made at the moment of its creation.²⁰

This can lead to missteps that go unnoticed by professionals, patients, and decision makers, so that monitoring the status of CPGs is of great importance to maintain in force the recommendations issued by the guides. A study by Shekelle et al.²¹ showed that most CPGs remain valid for a period of 3.6 years.

Regular monitoring of existing CPGs, and defining the maximum time to ensure their dissemination, is one way to ensure that CPG recommendations are used by professionals and that they are current. However, evidence regarding the best way to monitor and update CPGs is limited, and many CPG development groups have no formal update procedure.^22-24 The updating of these guidelines is, therefore, a process that can be costly and time-consuming, similar to the development of a new CPG.²⁴

CPGs must be updated

Assessing the need to update a CPG is essential to ensure the effectiveness of its recommendations. An outdated guide can lead to malpractice by failing to include new available information (Annex 1).

The questions to be asked regarding the need to update are:

• Are there significant differences between the information with which the CPG recommendations were developed, and newly found evidence?
• Does this new information affect the recommendations in a relevant way?
• Does the degree of strength of the CPG recommendations remain the same?

The answer to these questions must start with the analysis of the CPG recommendations to be updated, its relevance, and its adaptation to new studies reviewed; i.e. one must assess to what extent the new results and the context (scientific, technological, sociological, cultural, and organizational) differ from the original CPG.

Types of CPG updates

The types of CPG updates include the following: full update, partial update, update without modification, or removal of the CPG (Table II).²⁵

Literature search to develop and update the CPG

For the integration of a CPG, it is vital to carry out an information search protocol that ideally should be done by a librarian with experience in the clinical area or health sciences, in order to comprehensively and systematically obtain the most available documents containing the best available clinical evidence.

In the initial part of the search protocol it is necessary to search for and define what the MeSH descriptors will be or, where appropriate, the free vocabulary terms to be used in the search strategies, always aiming to get the largest number of results in a timely and precise way to cover the content to be treated in the guide.

The search process should be carried out in the information sources to which one has access (which must also have scientific recognition), such as databases, meta search engines or specialized websites (PubMed, Embase, NGC, NICE, SIGN, for example).

The aim of the guide is to present information with the best available clinical evidence. In the search protocol development, CPG first will be looked for that are published on the subject in question, by scientific and academic institutions with recognition so that, once evaluated, they can be adopted or adapted to the national context.

If sufficient guidance on the subject of the CPG to be developed is not found, or it does not have the methodological or content rigor needed to be adopted or adapted to the reality of Mexico, it will be necessary to find other types of documents with the highest level of evidence possible.

The search protocol must be reproducible and validatable. This is so that, once it is finished, documents that support the CPG development have been selected and retrieved. This protocol will be sent to a librarian with experience in the clinical area or health sciences, who, in turn, will reproduce it and validate that the search process is relevant to the aims and objectives of the guide.

It is absolutely necessary to identify all published systematic reviews on the topic of interest. Systematic reviews allow one to assess the degree of relevance of the recommendations contained in the selected guidelines, and incorporate recent and relevant evidence to the adaptation process (if this is not included in the selected guides).

The search for systematic reviews should be conducted in the databases Medline, Lilacs, Tripdatabase, Cochrane Library, and CRD (Centre for Reviews and Dissemination). A specific search strategy must be developed for each of the databases, according to their characteristics and descriptors.

Another complementary resource that can be also considered in the search is the Health Technology Assessment (Evaluación de Tecnologías Sanitarias) database, which can be consulted free of charge at the following link: http://www.crd.york.ac.uk/crdweb/

One of the critical resources for required consultation in the identification of systematic reviews is the Cochrane Library.

In summary, the main purpose of the search is to obtain information that is

• Accurate, i.e. having agreement between what is looked for and what is found.
• Exhaustive: providing as many results as possible on the specific search.
• Coming from databases and scientific information sources or arbitrated by some authority on the subject.
• Free of selection bias, that is, independent of the preferences of the guide developers.

Once one starts developing the search protocol, one must know:

• The title of the guide being considered.
• The target population of the guide: sex and age group.
• The level of care that the guide is directed at: first, second, or third level.
• The intervention that the guide will address, for example, prevention, diagnosis, treatment, etc.
• The PICO questions.
• The descriptors, keywords, and terms related to the topic of the guide.

Using descriptors and the basic terms of the title, and a summary of the main systematic reviews and large trials should be enough to build new search strategies. This should be run from the full year which ended the original search forward and should be repeated when the update is almost complete to check relevant studies have been published. This is not recommended when new questions or new technologies arise requiring renewal. Search strategies, when appropriate, should be made with a more comprehensive approach (Algorithm 2).

• Recommended procedure: alerts of developments in NGC of AHRQ, NJL of the NHS. Division of Basic Tables, COFEPRIS. Accurate search for systematic reviews and large trials published in PubMed.
• Recommended Resources: NGC of AHRQ, NLH of the NHS, developing institutions (SIGN, NICE, Australian National Health and Medical Research Council- and NZGG), DARE, HTA and NHS, (Cochrane Database of systematic reviews) (see Annex 2).
• Other resources: TRIP database or Clinical Excellence; websites of scientific societies; PubMed.
• Clinical Practice Guidelines: if there is a quality updated CPG that answers questions appropriately, assess its adoption or use it as a reference point for updating the literature search.

Evidence classification systems and recommendation strength

The concept of evidence-based medicine (EBM) was developed by a group of internists and clinical epidemiologists, led by Guyatt, from the School of Medicine at McMaster University in Canada. In Sackett’s words, "EMB is the conscious, explicit, and judicious use of the best available clinical evidence to make decisions about the care of individual patients".²⁷

In essence, EBM aims to have the best scientific information available: the evidence to apply to clinical practice.

The stage of evidence presentation is the organization of available information as related to qualitative characteristics, design, and type of results from the available studies. The classification of evidence lets one make recommendations on the inclusion or exclusion of an intervention within the CPG.

There are different ways of grading evidence based on the scientific rigor of the study design; scales can be constructed for the hierarchical classification of evidence based on which recommendations can be established on the adoption of a specific medical procedure or health intervention.

Although there are different gradation scales for the quality of scientific evidence, they are all very similar to each other; some are presented in (Tables III, IV, V, VI).

Ethics and conflict of interest statement

In CPG preparation it is very important to consider the ethical issues that accompany the disease and the corresponding diagnostic and therapeutic procedures. The observance of bioethical aspects improves health care services through a more humane medical practice, a positive attitude towards patients, less paternalism in the doctor-patient relationship, and higher quality in medical decisions. Based on the above, it is crucial to consider the four initial principles of bioethics in the construction of the CPG.

Considering the above principles, it is important for authors developing and validating a CPG to declare whether or not there is a conflict of interest because the CPG presents a summary of recommendations whose content can influence decision making by different health professionals who use them in their clinical practice. It is important that the end user of the guides know the relationship that individual developer authors may have with the pharmaceutical industry, ensuring independence and transparency in its creation or updating.

A conflict of interest occurs in circumstances where professional judgment on a primary interest (such as patient safety or the validity of research) may be influenced excessively by a secondary interest, be it a financial benefit, desire for professional advancement, recognition of personal achievement, or favors to friends, relatives, students, or colleagues.

Another way of understanding conflict of interest is when there are different types of interest: personal and non-personal. Personal interest involves any direct payment to a member of the group; and non-personal interest involves payment that benefits a department or organization where the member works, although they do not receive it personally.

The interests usually declared are financial, not because they are more harmful than others, but because they are measurable and can be evaluated objectively. The potential conflict of interest can exist regardless of whether or not the professional believes that such relations have influence on their scientific judgment. Relationships that can link a health professional with the pharmaceutical industry are classified into six types of financial interactions.

• Support to attend meetings and conferences (registration, travel grants, etc.).
• Speaker fees at a meeting organized by the industry.
• Funding of educational programs.
• Support and funding of research.
• Employment as a consultant for a pharmaceutical company.

Being a shareholder or having financial interests in a pharmaceutical company.

The statement must be recorded and documented in a written form specially designed for this purpose. The form must be requisitioned by the declarant and submitted to the CPG coordinator. Ideally this process should be repeated at each meeting of the development group if there has been any development regarding the interests initially declared.

If a member of this group declared a potential conflict of interest in all (development of evidence and recommendations) or in a limited part of the guide (including articles that favor a drug), their participation in the development process should be assessed by the leader of the guide, along with the project coordinator, to determine whether the declared interests are such that the professional is discouraged from being part of the development group or just in some phases of the process.

Conclusions

CPGs are useful tools for standardizing decision-making processes and improving the quality of care.

In Mexico, there is a legal basis and clinical support to develop CPGs that help the decisions of healthcare professionals and their patients regarding the correct health care for specific clinical circumstances.

CPGs are aimed at professionals and patients with the aim of providing information for decision-making in health interventions. Their origins have foundations in EMB and their development is intended to reduce the variability of medical practice to ensure optimum quality and improve health care.

It is essential to have the tools that allow us access to the right information in terms of quantity, quality, and timeliness, to contribute to better decision making, since under the premise of equity in care, health care should not vary between medical and health institutions.

It is evident that the use of CPGs is currently an urgent need in medical intervention to synthesize the state of scientific knowledge and establish a balance between risks and benefits, and the ability to provide alternative treatments for each patient.

The design and development of CPGs helps define standards to improve medical care by incorporating current scientific knowledge. Selecting quality scientific knowledge requires that whoever develops the CPG have the necessary tools, the ability to critically read the literature, and also the capacity for synthesis and clear exposition, which facilitates the interpretation and implementation of the CPG in the local context.

The challenge in advancing CPGs is on the one hand updating it to incorporate evidence and recommendations based primarily on systematic reviews of the scientific literature. On the other hand, we must improve the process to generate the key recommendations that can be practical and feasible for the user, and serve as a starting point to generate research on the effectiveness and cost-effectiveness in the national context, as alternatives giving more validity and quality in the performance of medical practice.

CPGs are not tools that restrict freedom of health personnel in clinical practice, since they must provide recommendations flexible enough to adapt to the characteristics of a particular patient ("there are no sicknesses, only sick people").

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