Evidence-Based Practice

Evidence-Based Practice

Learning Objectives

• The Cochrane Database of Systematic Reviews.
• Randomised controlled trials.
• Meta-analysis.
• Quality Adjusted Life Years.
• Clinical Guidelines

Development of Experimental Evidence

• How we are managing evidence.
• QALYs, NICE.
• Getting a quick, accurate, authoritative answer to a question on clinical evidence.

Hippocrates (460-370 BC)

• Stated the importance of prescribing regimens for the good of patients, according to ability and judgment, and never doing harm.
• Highlighted the practice of not performing certain procedures (cutting for stone) and leaving it to specialists.
• Emphasized entering houses only for the good of patients, avoiding intentional ill-doing and seduction.
• Stressed the importance of keeping knowledge gained in the profession or daily commerce secret.

Sir Austin Bradford-Hill (July 1897 – April 1991)

• English Epidemiologist and Statistician.
• Conducted the first clinical trial – Streptomycin in tuberculosis published 1948.
• Famous for criteria of causation.

Sir Archie Cochrane (Jan 1909 – June 1988)

• Scottish doctor famous for his book – Effectiveness and Efficiency – Random Reflections on Health Services (Nuffield Provincial Hospitals Trust) 1972.

• Randomized control trial is the hero of the book.

• Clinicians in the "care" part of the National Health Service (NHS) who either fail to carry out such trials or succeed in ignoring the results if they do not fit in with their own preconceived ideas are the villains.

• Subsequent report in the BMJ (1978) of a study he made of 18 countries:

  “ …the indices of health care are not negatively associated with mortality, and there is a marked positive association between the prevalence of doctors and mortality in the younger age groups. No explanation of this doctor anomaly has so far been found. Gross national product per head is the principal variable which shows a consistently strong negative association with mortality. ” doi:10.1136/jech.32.3.200

Sir Ian Chalmers (b June 1943)

• Clinician and Health Researcher.
• Oxford Database of Perinatal Trials (ODPT) 1986.
• Effective Care in Pregnancy and Childbirth 1989.
• Guide to Effective Care in Pregnancy and Childbirth. 1989.
• Co-founder of the Cochrane Library of Systematic Reviews in 1993.
• British organization running 53 review groups around the world with 30,000+ volunteers contributing their expertise.
• Invaluable resource of systematic reviews of randomised controlled trials.

Cochrane Library

• Trusted evidence.
• Informed decisions.
• Better health.
• The Cochrane Database of Systematic Reviews (CDSR) is the leading journal and database for systematic reviews in health care.
• The CDSR includes Cochrane Reviews (systematic reviews) and protocols for Cochrane Reviews as well as editorials and supplements.
• The CDSR (ISSN 1469-493X) is owned and produced by Cochrane, a global, independent network of researchers, professionals, patients, carers, and people interested in health.
• The CDSR covers any topic relevant to health care, including health services.
• The Cochrane library now has more than 7500 systematic reviews

Evidence-Based Practice

• Evidence-based practice is a systematic approach to decision-making that involves using the best available evidence to inform decisions and actions.

Evidence-Based Medicine

• Translation of uncertainty to an answerable question and includes critical questioning, study design and levels of evidence
• Systematic retrieval of the best evidence available
• Critical appraisal of evidence for internal validity that can be broken down into a range of aspects including…. Evaluation of performance[2005] Sicily Conference of Evidence-Based Health Care Teachers and Developers Systematic Review and Delphi Survey. doi:10.1001/jamanetworkopen.2018.0281

Hierarchy of Experimental Evidence

• Meta-analyses (strongest)
• Systematic reviews
• Randomized controlled trials
• Cohort studies
• Case-control studies
• Case report
• Expert opinion (weakest)

Randomized Controlled Trial (RCT)

• A randomized controlled trial (RCT) is an experimental form of impact evaluation in which the population receiving the programme or policy intervention is chosen at random from the eligible population, and a control group is also chosen at random from the same eligible population.
• A randomized controlled trial is a form of scientific experiment used to control factors not under direct experimental control.

Meta-Analysis

• A meta-analysis is the statistical integration of evidence from multiple studies that address a common research question. By extracting effect sizes and measures of variance, numerous outcomes can be combined to compute a summary effect size.
• Meta-analysis is a quantitative, formal, epidemiological study design used to systematically assess the results of previous research to derive conclusions about that body of research.

Managing Evidence

• Potentially unmanageable volume of evidence.
• Evidence needs rationalizing.
• Evidence has to be compatible with the clinical situations in which I find myself.
• The solution has been provided in three places:
  • Clinical Guidelines
  • National Institute of Health and Care Excellence
  • BMJ Clinical Guideline Concise and similar

Clinical Guidelines

• Made the volume of research manageable for the individual clinician.
• Resolved clinicians’ disagreement on appropriate management.
• Funding from special interest groups and government.
• Expertise became available – specialist, generalist, the patient and public.
• Administrative resource included to handle large volumes of research evidence.

Source of Guidelines

• Professional Societies and Associations – British Thoracic Society, European Respiratory Society, Medical Royal Colleges
• Stakeholder Associations - Asthma + Lung UK
• Government supported national bodies – SIGN, NICE

Risk of Duplication – Consider Chronic Obstructive Pulmonary Disease - COPD

• NICE
• GOLD COPD
• British Thoracic Society
• European Respiratory Society
• American Thoracic Society
• All produce independent guidelines and some guideline committee participants sit on two or three committees

Too Much Evidence?

• In 2019, 80 systematic reviews were published each day compared to 4 in 2000 and 14 in 2010
• Thousands of RCTs are published every day.

Impact of Too Much Evidence

• Volume, especially of clinical guidelines becomes unmanageable
• Statistically significant benefits may not be clinically important
• The evidence may not apply to people with complex multimorbidity and may become unintelligible
• There needs to be continuing rationalization

NICE (National Institute for Health and Care Excellence)

• Independent organization funded by the Department of Health
• Provides national guidance on the promotion of good health, prevention and treatment of ill health.
• Established in 1999 as a NHS Special Authority.
• In 2013 it become the National Institute for Health and Care Excellence and now covers social care.
• It left the NHS to become a non-departmental public body.

Why the Need for NICE?

• Address inappropriate variations in clinical practice and “post-code” access to expensive treatments
• Support clinicians to keep up to date with relevant new evidence
• Assess the “value” (cost effectiveness) of new and existing treatments
• Encourage innovation

Core Principles of NICE

• Comprehensive Evidence Base
• Expert Input
• Public Patient and Carer Involvement
• Independent Advisory Committees
• Genuine Consultation
• Regular Review
• Open and Transparent Process

QALYs (Quality Adjusted Life Years)

• Two dimensions – added duration of life quality of that life
• Quality from 0 - 1, 0 = no quality, 1 = full quality
• QALY = Added\ life \times Quality\ during \ that\ added\ time.
• QALYs are assessed by health economists They combine the outcome measure in years of quality of life gained and the cost of that gain.

NICE and Guidelines

• Evidence, Expert opinion, Observational studies, RCTs, Cohort and case control studies, Systematic reviews.
• NICE Guideline Committee: Multidisciplinary, Specialists, Generalists, Members of public, Patient groups, Committee staff.
• Draft guideline published for comments.

NICE's Activities Over the Years

• Growth in NICE's activities over the years (2000-2014) - Social care, CCG OIS, Evidence updates, Evidence summaries, Diagnostics, Quality standards, Medical devices, QOF, QIPP, Accreditation, Public health, Interventional procedures, Clinical guidelines, Technology appraisals
• COG OIS provides a set of outcome indicators that allow Clinical Commissioning Groups to benchmark their quality performance.
• QOF stands for the Quality and Outcomes Framework used in general practice.
• QIPP is support for the NHS's Quality, Innovation, Productivity and Improvement programme, aimed at improving the quality of care in ways that also increase the service's productivity and efficiency.

Easy Access to Evidence: Clinical Evidence Concise

• BMJ publication
• Guidance on 158 conditions currently
• Includes a synopsis of guidance from a wide variety of sources – NICE Clinical Guidelines, Professional Group Guidelines, Stakeholder Guidelines, International Guidelines
• Integral to the working day of many junior doctors

Integrating Evidence with the Clinical Record

• Health informatics - linking evidence with the electronic patient record

• Learning health system - integrated AI in the electronic record

• A Learning Health System (LHS) is an advanced approach to healthcare where data and experiences from clinical practice are continuously collected, analyzed, and used to improve patient care.

• Data driven / Integrated care / Patient centred

  • EPR – Patient’s demographic data, biometric data, disease and treatment data, presenting history and examination data + Clinician’s action: – proposed diagnosis, proposed investigation; proposed treatment
  • EPR + learning health system provides an integrated assessment