The Canadian Task Force on Preventive Health Care (CTFPHC) is composed of experts who develop recommendations for clinical preventive services delivered by Canadian primary care practitioners. The CTFPHC is responsible for prioritizing the topics that will be reviewed and works with the Global Health and Guidelines Division of the Public Health Agency of Canada to define the analytic framework and scope of each topic. In the preparation of evidence reviews and the development of recommendations for each topic, the CTFPHC collaborates with two evidence review and synthesis centres and the Global Health and Guidelines Division. The CTFPHC also leads knowledge translation (KT) activities to promote guideline reach and uptake.
Message From the Chair
Greetings! In this issue, I am pleased to announce the release of our two newest clinical practice guidelines. In March 2016, the CMAJ published the CTFPHC’s Recommendations on Screening for Lung Cancer in Primary Care and Recommendations on Screening for Developmental Delay. For more information about the lung cancer and developmental guidelines, systematic reviews, and associated KT tools, please visit the CTFPHC lung cancer guideline page and the CTFPHC developmental delay guideline page.
As always, we appreciate your interest in the CTFPHC, and we encourage you to stay up to date on our work by visiting our website at www.canadiantaskforce.ca.
Marcello Tonelli, MD SM
Release of the CTFPHC’s Lung Cancer Screening Guideline
In March 2016, the CMAJ published the CTFPHC’s eleventh guideline, which addresses screening for lung cancer. Lung cancer is the most common cause of cancer-related deaths and the most commonly diagnosed cancer among Canadians. It is estimated that 26,000 Canadians were diagnosed with lung cancer in 2015 and 20,900 died from the disease. Mortality is extremely high in late-stage lung cancer but much lower in earlier stages. The incidence of lung cancer is currently higher in men than in women (although this gap is beginning to narrow), and more than 85% of cases are related to smoking tobacco. Those with a history of heavy smoking are at the greatest risk for lung cancer.
The CTFPHC’s lung cancer guideline presents recommendations for screening for lung cancer in adults 18 years and over. These recommendations do not apply to individuals who have a history of lung cancer or those with suspected lung cancer.
The CTFPHC based its recommendations on the overall balance between the possible benefits and harms of lung cancer screening. Specifically, it weighed the potential benefits of early disease detection against the harms of overdiagnosis and invasive follow-up testing that can result in false positives, major complications, or death.
For adults aged 55–74 years of age who are current or former smokers with at least a 30 pack-year smoking history (i.e., 1 pack a day for 30 years or equivalent), the CTFPHC recommends offering three screens with low-dose computed tomography (LDCT), each at one-year intervals. These screens should be carried out only in health care settings with expertise in early diagnosis and treatment of lung cancer. This is a weak recommendation based on low-quality evidence.
For all other adults, regardless of age, smoking history, or other risk factors, the CTFPHC recommends against screening for lung cancer with LDCT. This is a strong recommendation based on low-quality evidence. Evidence shows that there is no clear benefit of LDCT screening for these individuals, but they would be susceptible to the potential harms associated with screening (e.g. false-positive results, complications from invasive follow-up tests, and overdiagnosis).
We also recommend against screening patients of any age for lung cancer with chest x-ray. This strong recommendation is based on low-quality evidence. Available evidence suggests that there is no impact of screening for lung cancer with chest x-ray on lung-cancer-specific or all-cause mortality, but there are established harms.
We encourage primary care providers to discuss the possible harms and benefits of screening with patients who are interested in getting screened. In adults with symptoms of lung cancer (e.g., hemoptysis, weight loss, and dyspnea), regardless of age or smoking history, clinicians should consider diagnostic testing as clinically indicated.
To accompany its screening for lung cancer guideline, the CTFPHC developed a 1000-person tool and an FAQ sheet for clinicians. The 1000-person tool provides guidance for patients on the potential harms and benefits of screening for lung cancer. The FAQ sheet provides answers to common questions that clinicians may have about screening for lung cancer. Copies of the 1000-person tool and clinician FAQ can be downloaded for free from the CTFPHC lung cancer guideline page. As always, the CTFPHC encourages members of the public to discuss screening for lung cancer with their primary care practitioner, who is aware of their health background and family history.
Release of the CTFPHC’s Developmental Delay
The CMAJ published the CTFPHC’s twelfth guideline in March 2016. This latest guideline addresses screening for developmental delay in children aged 1 to 4 years who are not at high risk for developmental delay, have no signs suggestive of a developmental delay, and whose parents or clinicians have no concerns about development. This recommendation does not apply to children who present with signs, symptoms, or parental concern that could indicate developmental delay or whose development is being closely monitored because of identified risk factors, such as premature birth or low birth weight. The guideline does not offer guidance about developmental surveillance, case finding, or diagnosis.
The CTFPHC did not find any evidence that screening for developmental delay improved health outcomes. Although there was some evidence suggesting that treatment of certain types of developmental delay is beneficial compared with no treatment, there was no evidence that screening children without recognized signs of DD is necessary to obtain this benefit. In addition, there was no evidence that interventions improve outcomes compared to standard care when they are offered to children who test positive for DD but do not have any other signs of DD and whose parents and clinicians are not concerned about developmental delay.
The CTFPHC places a relatively higher value on the absence of direct evidence showing that screening is beneficial, the poor diagnostic accuracy of screening tests, the risk of false positives that could result from screening, and the potential for screening to divert resources from the treatment of children with clinically evident DD. The CTFPHC places a relatively lower value on indirect evidence from the few small studies that suggest a benefit of treatment.
To accompany its screening for developmental delay guideline, the CTFPHC developed an FAQ sheet for clinicians. The FAQ sheet provides answers to common questions that clinicians may have about screening for developmental delay. Copies of the clinician FAQ are available to download for free from the CTFPHC developmental delay guideline page. As always, the CTFPHC encourages members of the public to discuss screening for developmental delay with their primary care practitioner, who is aware of their child’s health background and family history.
History of the CTFPHC
The CTFPHC was established in September 1976 by the Conference of Deputy Ministers of Health of the ten Canadian provinces. It was previously known as the Canadian Task Force on Periodic Health Examination. The original task force was chaired by Dr. Walter O. Spitzer and its members included epidemiologists, health care researchers, and clinicians.
From 1976–1979, a method was developed by the task force for weighing scientific evidence to make recommendations for or against including preventive measures in periodic health examinations of asymptomatic patients.
The first CTFPHC report was published in 1979. It reviewed the scientific evidence for the preventability of 78 conditions and arrived at an important central recommendation: the undefined “annual check-up” should be replaced with a series of agespecific “health protection packages” implemented during medical visits for other purposes.
From 1979 to 1994, the CTFPHC published nine updates evaluating the preventability of 19 conditions not considered previously and revising 28 earlier reports in the light of new evidence.
In 1994, the CTFPHC published “The Canadian Guide to Clinical Preventive Health Care,” a landmark compilation of recommendations for 81 conditions. This 1009-page volume, known as “The Red Brick,” became a standard reference tool for Canadian primary care clinicians.
In the 1980s, the CTFPHC’s approach was adopted with minimal modification by the United States Preventive Services Task Force (USPSTF). It was applied successfully by both the Canadian and U.S. Task Forces to evaluate the preventability of over 200 conditions and has achieved international recognition as a basis for developing guidelines for clinical practice and public health policy.
The CTPFHC was disbanded in 2005, but it was re-established in 2010 with the support of the Public Health Agency of Canada and the Canadian Institutes of Health Research.
GRADE: Question and Answer
The CTFPHC develops its guidelines using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method. This is an internationally recognized method for evaluating systematic review evidence to develop clinical practice guidelines. In each issue of the CTFPHC newsletter, we will discuss one frequently asked question about GRADE posed by primary care practitioners.
According to GRADE, what is the strength of a recommendation based on?
The strength of a recommendation is based on four factors: (a) the trade-off between the harms and benefits of an intervention, (b) the quality of evidence underlying the recommendation, (c) patient values and preferences related to the intervention, and (d) resources available to deliver the intervention.
The strength of a recommendation tells practitioners how the recommendation should be applied in practice. A strong recommendation means that most patients would be well served by the recommended course of action. A weak recommendation means that many patients would want the recommended course of action but some may not. When a recommendation is weak, practitioners should have an informed discussion with patients and help them make a decision that is consistent with their values and preferences.
Opportunities for Engagement
Patient Engagement in Guideline Development
The CTFPHC now engages patients in its guideline development process. Specifically, the CTFPHC recruits patients to provide input at up to two stages of the process: (1) when outcomes are selected for inclusion in the systematic review protocol that informs the guideline and (2) when the guideline recommendations are developed. The CTFPHC uses feedback provided by patients to guide the search for evidence on the harms and benefits of preventive health care interventions and to develop KT tools to accompany the guidelines.
The CTFPHC is currently engaging patients in Stage 2 for its guideline on screening for hepatitis C and screening for abdominal aortic aneurysm.
Usability Testing of Practitioner Tools
The CTFPHC produces practitioner tools to support each of its guidelines. To ensure that the content, layout, navigation, and aesthetics of these tools are appropriate and useful for practice, we conduct usability testing with practitioners. If you are interested in reviewing and providing feedback on one of our upcoming guideline tools, please email Kavitha Thiyagarajah, research assistant, at email@example.com for more information. Note that we offer $100 compensation for a one-hour telephone interview.
Guidelines in Progress
Forthcoming guidelines developed by the CTFPHC will focus on the following topics:
- Screening for hepatitis C
- Tobacco smoking prevention and cessation in children and adolescents
- Screening for abdominal aortic aneurysm
- Screening for glaucoma and visual acuity
- Screening for esophageal cancer
- Antenatal screening for birth defects
- Antenatal screening for asymptomatic bacteriuria
Is there a preventive health topic that you would like to see the CTFPHC develop a clinical practice guideline for? Let us know what you are passionate about! We accept topic suggestions on a rolling basis and would love to hear from you. To submit a suggestion, please email us at firstname.lastname@example.org with the subject line “Topic Suggestions”.
Suggestions for the next newsletter
Is there a subject that you would like to see addressed in the next issue of the CTFPHC newsletter? Let us know what you’d like to see covered! We accept suggestions on a rolling basis. To submit a suggestion, please email Kavitha Thiyagarajah, research assistant, at email@example.com with the subject line “Newsletter Suggestions”.