ANM 100 Week 14 Research 2 PDF
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Canadian College of Naturopathic Medicine (CCNM)
Dr. Monique Aucoin ND MSc
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Summary
This document is a presentation on various types of research methods, including Randomized Controlled Trials (RCTs), observational studies (cohort and case-control studies), and other research designs, along with concepts relevant to Naturopathic Medicine, including the hierarchy of evidence.
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ART AND PRACTICE: RESEARCH WEEK 2 DR. MONIQUE AUCOIN ND MSc ANM 100 Week 13 QUESTION: WHAT DO WE DO WHEN WE HAVE CONFLICTING INFORMATION FROM DIFFERENT TYPES OF RESEARCH? OUTCOMES Identify and summarize the basic types of clinical epidemiological studies including: randomized controlled trials,...
ART AND PRACTICE: RESEARCH WEEK 2 DR. MONIQUE AUCOIN ND MSc ANM 100 Week 13 QUESTION: WHAT DO WE DO WHEN WE HAVE CONFLICTING INFORMATION FROM DIFFERENT TYPES OF RESEARCH? OUTCOMES Identify and summarize the basic types of clinical epidemiological studies including: randomized controlled trials, cohort studies, case-control studies, systematic reviews, case reports, n-of-1 studies, and whole systems research. RESEARCH STUDY METHODOLOGIES HIERARCHY OF EVIDENCE Wellness blogger NEW AND VERY MUCH UNIMPROVED NUTRITION HIERARCHY OF EVIDENCE Celebrity Personal anecdote from your cousin’s best mate’s brother’s girlfriend Dr Google Info Commercial Personal testimony of a stranger overheard on public transit Highly educated individual with university dress in something totally unrelated to health/nutrition (ie. Law, Journalism) N=1 studies OTHER TYPES OF EVIDENCE Textbooks Peers, Elders Qualitative research Traditional/Historical use N of 1 Whole systems research EXPERIMENTAL/INTERVENTION STUDIES DO Something to the patient, OBSERVE what happens Does the treatment change the likelihood of the outcome? Treatment TIME RANDOMIZED CONTROLLED TRIAL: CHARACTERISTICS Defined population (inclusion/exclusion criteria) 2(+) Groups: Treatment arm + Comparison arm Prospective: look forward in time Tx A TIME Tx B RANDOMIZED CONTROLLED TRIAL: CHARACTERISTICS Randomized: Equal chance of being assigned to the intervention or control group Control group: accounts for natural course of illness, placebo effect, confounding factors May have Blinding: minimize expectation effect RCT Use: **Best Design for confirming cause/effect** OTHER KINDS OF INTERVENTION STUDIES Cross-over: everyone gets intervention AND comparison Image source: Cochrane OTHER KINDS OF INTERVENTION STUDIES Preference (controlled, not randomized): choose between different arms (ex. Cancer survivors, pick MBT or Tai Chi) Open-label, Pre/Post: everyone gets the intervention (know it), assess changes before and after intervention Treatment TIME DESIGN A STUDY! Question: Dose a maternal diet deficient in B12 impact fetal brain development? appropriate study design? Clinical trial? Case report? Vandenbroucke JP. When are observational studies as credible as randomised trials?. The Lancet. 2004 May 22;363(9422):1728-31. OBSERVATIONAL STUDIES Exposure NOT controlled by the researcher They ask: Is there a relationship between a risk factor (or health factor) and an outcome (harm or benefit) Ex. Is high intake of blueberries associated with a lower risk of cancer? Is increased stress associated with an increased risk of a heart attack? OBSERVATIONAL STUDIES TIME COHORT STUDY Compare Incidence Exposed CROSS-SECTIONAL STUDY TIME Un-exposed TIME Compare Prior Exposure Diseased TIME Non-Diseased CASE-CONTROL Compare Current Disease Status and Current Exposure COHORT STUDY Recruit the cohort (outcome is NOT present) Assess risk/health factors (creates a comparison grp) Follow over time See who develops the outcome “longitudinal” “prospective” TIME COHORT STUDY Exposed TIME Un-exposed Compare Incidence COHORT EXAMPLE: SATURATED FAT AND CVD Who developed CVD? Is there a difference between the groups? High sat fat diet -People without CVD -Ask about sat fat COHORT STUDY consumption TIME Exposed TIME Un-exposed Low sat fat diet Compare Incidence CASE-CONTROL Outcome is PRESENT at the beginning of the study Looks backwards in time for exposure (how much meat did you eat 10 years ago?) TIME Compare Prior Exposure Diseased TIME Non-Diseased CASE-CONTROL OBSERVATIONAL STUDIES: STRENGTHS Can study any question (harmful exposure, lack of a beneficial exposure) Can be less expensive or faster CASE CONTROL EXAMPLE Find people with AND without CVD -Is there a difference? TIME Compare Prior Exposure Diseased TIME Non-Diseased -Ask them to think about the past -high or low saturated fat diet? CASE-CONTROL CASE CONTROL STUDIES Strengths Weaknesses • Can look at rare outcomes • Assignment to comparison grp is NOT random • Faster (no waiting time, minimal loss of participants) • Hard to assess temporality (ex. recall bias) CROSS-SECTIONAL STUDIES Outcome is PRESENT at the beginning of the study CROSS-SECTIONAL STUDY Assess exposure and outcome at ONE time point Ex. Patients with CVD and healthy controls, ask about CURRENT meat intake Compare Current Disease Status and Current Exposure CROSS-SECTIONAL EXAMPLE CROSS-SECTIONAL STUDY Find people with AND without CVD Ask about sat fat in diet Is there a difference? Compare Current Disease Status and Current Exposure CASE REPORTS, CASE SERIES Report previously undocumented events (success, adverse reaction) May lead to further action Real patients and real clinical approaches BUT concerns about bias and generalizability N OF 1 STUDY Randomized, double blind, multiple crossover comparisons in an individual patient. “individualized RCT” - compare to self while taking the real treatment vs taking the comparison (ex. patient with hypertension: magnesium vs placebo or blood pressure medication) N OF 1 TRIAL DESIGN PRECLINICAL STUDIES In vitro: outside the body: cell lines, organs In vivo: in non-disease model: healthy human to study pharmacokinetics (absorption, elimination), animal models Base of the EBM hierarchy Basic knowledge to build on, allows to innovation, highly controlled, ‘ethical’, study mechanisms of action SYNTHESIS RESEARCH Why? TIME!! Incorporate the results of individual studies together Draw bigger conclusions NARRATIVE REVIEWS Researcher combines some of the research on a topic Reports on the collection of evidence Often does NOT describe how they searched and how they decided to include certain studies High risk of bias – results often consistent with author’s hypothesis SYSTEMATIC REVIEWS Explicit and rigorous methods to: 1. Identify (2+ databases, specific inclusion/exclusion criteria) 2. Critically appraise 3. Synthesize (combine) Scientific investigation with pre-planned methodology Enormous effort to minimize bias META-ANALYSES Statistically combine the results of studies in a systematic review Ex. 5 studies with 20 participants → 1 study with 100 participants Visual representation of the studies (Forest Plot) WHOLE PRACTICE RESEARCH Need: Do the results of RCTs apply to real clinical practice of naturopathic medicine? Issues: RCT often use one intervention to treat one disease in a uniform patient population Naturopathic medicine: often complex interventions, prescribed in an individualized way, to patients with complex health conditions WHOLE PRACTICE/SYSTEMS RESEARCH Assess entire system of care vs individual treatments of modalities Ex. individualized acupuncture treatments vs testing 3 set acupuncture points Ex. Individualized homeopathy vs a single remedy Ex. Naturopathic medicine as a whole WSR TRIAL DESIGN Goal: accurately study what is actually done in the real world Modified RCT design: use an entire system of medicine vs individual therapy W H AT ’ S T H E M E T H O D O LO G Y ? a) Systematic Review b) Intervention study c) Cohort Study d) Case-Control Study W H AT ’ S T H E M E T H O D O LO G Y ? a) Systematic Review b) Intervention study c) Cohort Study d) Case-Control Study GROUP WORK WRAP UP AND QUESTIONS ANY THOUGHTS OR INSIGHTS OR N E W P E R S P E C T I V E F R O M T O D AY ’ S M AT E R I A L ?