Living evidence 3


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Living evidence 3

  1. 1. Translating research into practice Wendy McDonald RN MPH&TM
  2. 2. Meaning of Evidence ?Evidence in best practice includes: Research evidence Clinical knowledge - experience of the individual practitioner Patient and practitioner preference Basic principles from theory and logic
  3. 3. Process Defined question Identify pertinent evidence Exhaustive search strategy Critically appraise & synthesize Reported in standard format Implement evidence into practice considering patient preferences & values
  4. 4. Where do you find the evidence?
  5. 5. Finding the information Electronic databases Journal Articles (electronic and paper) Internet Patient information Healthcare records Practice based data Textbooks
  6. 6. Examples of Where to FindEvidence Electronic Search Engines Web sources for EBP guidelines Professional Organizations LiteratureDetermine what the search will be from what the question focuses on.
  7. 7. Different types of Research Methods… Randomised Controlled Systematic Meta-Analysis Trial Review Cohort Study Quantitative Case Control Study Descriptive Studies Qualitative
  8. 8. Quantitative Research In quantitative studies, researchers use objective, quantifiable data (such as blood pressure or pulse rate) or use a survey instrument to measure knowledge, attitude. Quantitative research involves analysis of numerical data.
  9. 9. Types of Quantitative Research Randomized Controlled Trials Cohort study Descriptive study Case control study
  10. 10. Randomized Controlled Trials RCT’s The randomized controlled trial is one of the simplest yet powerful tools of research. RCTs are quantitative, comparative, controlled experiments in which investigators study two or more interventions in a series of individuals who receive them in random order.
  11. 11. Randomized Controlled Trials cont. RCT - A study in which people are allocated at random (by chance alone) to receive one of several clinical interventions. One of these interventions is the standard of comparison or control. The control may be a standard practice, a placebo, or no intervention at all. RCT seek to measure and compare the outcomes after the participants receive the interventions.
  12. 12. Cohort Study A cohort study is a research program investigating a particular group with a certain trait, and observes over a period of time. Observed for the occurrence of certain health effects over some period of time, commonly years rather than weeks or months. The occurrence rates of the disease of interest are measured and related to estimated exposure levels. Cohort studies can either be performed prospectively or retrospectively from historical records.
  13. 13. Case-control Study Investigates why certain people develop a specific illness, have an adverse reaction to a particular treatment or behave in a particular way.
  14. 14. Case-Control Study Research that retrospectively compares individuals who have a specific condition or disease ("cases") with a group of individuals without the condition or disease ("controls"). An application of medical history-taking that aims to identify the cause of disease among a group of people, or the cause-effect relationships of a condition of interest.
  15. 15. Design of a Case-Control Study Not Not Exposed Exposed Exposed Exposed Disease No Disease “CASES” “CONTROLS”
  16. 16. Case control study Often conducted to identify variables that might predict a condition or disease. Case-control studies have proved particularly useful in studying very rare conditions.
  17. 17. Descriptive StudyExamine differences in disease rates among populations in relation to :  age  gender  race  and differences in temporal or environmental conditions.
  18. 18. Descriptive Study Continued These studies are often very useful for generating hypotheses for further research. Useful in health service evaluation Can yield valuable information about a populations health status, and they can be used to measure risks. Used periodically to determine whether a particular service is improving, if serial description studies all show evidence of reduced sickness or disability rates over a period of years.
  19. 19. Descriptive Study Continued can only identify patterns or trends in disease occurrence over time or in different geographical locations. cannot ascertain the causal agent or degree of exposure. Examples include the U.S. National Health Care Survey, and periodic reports from cancer registries. Descriptive studies include case reports or case series, surveillance systems, correlational ( ecological studies) cross- sectional studies and cluster investigations.
  20. 20. Levels of Evidence
  21. 21. Systematic ReviewsUses a detailed search strategy to find relevant evidence to answer a clinical question.
  22. 22. Need for Systematic Reviews Complexity of the studies Volume of research literature on a given topic Bias existing in single studies Contradictory results from similar studies Sample size variation
  23. 23. Has the systematic reviewer done a goodjob?
  24. 24. Systematic Review A summary of evidence, conducted by an expert or expert panel on a specific topic. Uses rigorous process for  Identifying  Appraising  Synthesizing studies To answer a specific clinical question & draw conclusions & implications of all research available on a clinical question based on the data collected.
  25. 25. Value of Systematic Reviews Brings together and assesses all available research evidence into a single report about efficacy and effectiveness of specific practices Efficiently integrates valid information Provides a basis for rational decision making Resolves inconsistencies Establishes generalizability Assembles evidence Increases power and validity of the cause-and-effect relationship between intervention and outcome Limits bias and reduces chance effects
  26. 26. What do all of the numbers mean?
  27. 27. Meta-analysis combines the results of several studies that address a set of related research hypotheses. the statistical synthesis of the data from a set of comparable studies of a problem. yields a quantitative summary of the pooled results.
  28. 28. Meta-analysis continued aggregates the data and results of many studies, that used the same or similar methods and procedures. reanalyzing the data from all these combined studies. generates larger numbers, more stable rates & proportions for statistical analysis & significance testing than can be achieved by any single study.
  29. 29. Qualitative Research Qualitative researchers use methods such as interviews or narrative analyses to help understand a particular phenomenon Qualitative research involves analysis of data in non numeric forms such as words (e.g., from personal interviews), pictures (e.g., video), or objects (e.g., an artifact).
  30. 30. Both Triangulated approaches use both quantitative and qualitative methods Regardless of the method they use, researchers must adhere to certain approaches to ensure both the quality and the accuracy of the data and related analyses. The intent of each approach is to answer questions and develop knowledge using the scientific method.
  31. 31. TRIP Turning Research Into Practice (TRIP) Data Base Plus. A Data base doing research searches.
  32. 32. Implementing Research Findings inPractice (EBP Cycle) Need for a decision Implement findings Information need Appraise for Formulate validity and answerable usefulness Find evidence question from research
  33. 33. Examples of Nursing Research Randomized clinical trial examining best practice for orthopedic-pin site care Reliability of methods used to determine NG tube placement The effects of relaxation and guided imagery on preoperative anxiety Quality of life in patients with chronic pain The relationship of a preoperative teaching program for joint replacement surgery and patient outcomes
  34. 34. Importance of EBP Evidence-based practice helps nurses provide high- quality patient care based on research and knowledge. Rather than because “this is the way we have always done it,” or based on myths, hunches, traditions, or outdated textbooks.
  35. 35. Managing variance through EBPFor safe reliable healthcare
  36. 36. Study Design  Good Design = Control  Researchers need to control several variables that might affect the outcome of the study:  Environment  Subject selection  Treatment  Measurement
  37. 37. EBP - critically appraise theevidence for validity Validity Reliability Applicability - transferabilityThen synthesize that evidence.
  38. 38. Establishing Validity  Are the result of the study valid?  What were the results?  Will the results help me in caring for my patients?
  39. 39. Validity Validity- were the results of the study obtained via sound scientific research methods ? Bias or other confounding variables may compromise the validity of the findings.
  40. 40. Bias Anything that distorts study findings in a systematic way – often arises from study methodology. Any tendency to influence the results of a trial (or their interpretation) other than the experimental intervention.
  41. 41. Bias Bias is any deviation of results or inferences from the truth because of the way(s) in which the study is conducted.Blinding: A technique used in research to eliminate bias by hiding the intervention from the patient, clinician, and/or other researchers who are interpreting results.
  42. 42. Study Design Special types of control:  Blind: Unaware of assigned treatment.  Double blind: Provider also unaware of assigned treatment.  Placebo: A look-alike treatment with no efficacy.
  43. 43. Confounding Confounding variable: A variable which is not the one you are interested in but which may affect the results of trial.
  44. 44. Reliability – do the numbers add up? Do the results of the study have have sufficient influence on practice clinically and statistically? Can the results be counted on to make a difference when practitioners apply them to their practice? How large the reported intervention effect was & how precisely that effect was estimated. Together these determine reliability.
  45. 45. Reliability – do the numbers add up? Do the results of the study have have sufficient influence on practice clinically and statistically? Can the results be counted on to make a difference when practitioners apply them to their practice? How large the reported intervention effect was & how precisely that effect was estimated. Together these determine reliability.
  46. 46. Another case of “economy” class syndrome.Shouldn’t everyonetake an aspirin and wear stockings? What do you think about “flight socks?”
  47. 47. Applicability Whether or not the results of the study are appropriate for a particular a patient situation
  48. 48. Applying it to the Patient What do the results mean on average? What do they mean for this patient?
  49. 49. Consider Patient Values, Circumstances  Unique preferences  Concerns  Expectations  Financial resources  Social supports
  50. 50. Are the studies consistent? Are variations in results between studies consistent with chance? (Test of homogeneity: has low power) If NO, then WHY?  Variation in study methods (biases)  Variation in intervention  Variation in outcome measure (e.g. timing)  Variation in population
  51. 51. Critical Appraisal Terminology Null Hypothesis P-value Confidence intervals Relative vs Absolute Risk Reduction
  52. 52. Null Hypothesis States that there is no  Tylenol is better than relationship between the Advil for headaches variables being studied.  Exercising 30 minutes a Opposite of what you are day is good for your trying to find out. health  Lefthanders are prone to accidents
  53. 53. P-value Probability that the  Small p-value dismiss outcomes are due to chance chance  Large p-value means Accepted reference that anything is possible point is .05 (chance, actual effect, or confounding factors) Less than .05 is statistically significant
  54. 54. Statistical Significance  How strong are the statistical findings?  What is the strength of the associations/ differences between 2 or more groups?  What is the proportion of the variance that is accounted for?  Statistical significance p-value 0.05 is accepted in nursing.
  55. 55. Confidence interval Confidence interval (CI): The range around a studys result within which we would expect the true value to lie. CIs account for the sampling error between the study population and the wider population the study is supposed to represent.
  56. 56. Confidence Intervals Quantifies the uncertainty in measurement. A 95% confidence interval (CI) means that one can be 95% confident that the population value falls within a certain range Example: A study states that 40% of a sample of 1000 people are smokers with a CI of 95% +/- 3% means the frequency of smoking is between 37% and 43%.
  57. 57. Risk Relative Risk or risk ratio (RR) is the risk for achieving an outcome in the treatment group relative to that in the control group Relative Risk Reduction (RRR) is the increase in outcome with the treatment compared to the control (often expressed as a percentage) Absolute Risk Reduction (ARR) is the difference in outcome rates for two groups, usually treatment and control
  58. 58. Relative Risk or Risk ratio Indicates the likelihood (i.e. Risk) that the outcome would occur in one group compared to the other.
  59. 59. Relative Risk Reduction Not a good way to compare outcomes Amplifies small differences and makes insignificant findings appear significant Does not reflect the baseline risk of the outcome event Can make weak results look good Making weak results look good makes them popular, thus they are reported in many journal articles RRR can mislead
  60. 60. Absolute Risk Reduction A better statistic to evaluate outcome Does not amplify small differences, but shows the true difference between the experimental and control interventions
  61. 61. Is the review any good?FAST appraisal Question – What is the PICO? Finding  Did they find most studies? Appraisal  Did they select good ones? Synthesis  What do they all mean? Transferability of resultsApplicability – will the results help me care for my patients?
  62. 62. Critical Appraisal of Quantitative Studies Why was the study done? What is the sample size? Are the measurements of major variables valid and reliable? How were the data analyzed? Where there any untoward events during the conduct of the study? How do the results fit with previous research in the area? What does this mean for clinical practice? Melnyk /Fineout-overholt 2011
  63. 63. Critical Appraisal of Qualitative Evidence Are the results valid/trustworthy and credible? Are the implications of the research stated? What is the effect on the reader? What were the result s of the study? How does the research identify the study approach? Is the significance/importance of the study explicit? Is the sampling study clear and guided by the study needs? Are data collection procedures clear? Are data analysis procedures described? Melnyk/ Fineout-overholt 2011
  64. 64. Assessing the Studies Our job as critical readers is to determine whether the weakness is serious enough to warrant reinterpretation of the studys finding. We need to question whether the study measures what it intended to measure and whether the researchers have accounted for bias and confounding variables.
  65. 65. References Greiner, A., & Knebel, E., (Eds.). (2003). Health professions education: A bridge to quality. Washington, DC: The National Academies Press. Bio medical library University of Minnesota, Evidence Practice (power point) Malloch, K., Poter-OGrady, T., (2006)Introduction to Evidence -Based Practice in Nursing and Healthcare . Sudbury, MA, .Jones and Bartlet
  66. 66.  Ireland M. C.(2010) Evidence -Based Practice What does it mean? Innovations and Perspectives Virginia Department of Education. 1,2 Glasziou P. Introduction to EBM 2010(power point) Moseley, M., Evidence - Based Practice - an opportunity for nursing (2006) (power point) Rocky Mountain University Provo, Utah.
  67. 67.  Melnyk, Fine-Overholt Evidence based practice (2011). Evidence-based Practice in Nursing & Healthcare. 2nd edition. Philadelphia PA : Lippincot Williams & Wilkins Oakes, J. Evidence Based Practice for Beginners (power point) Dontje K. J.(2007)Evidence-Based Practice: Understanding the Process .Topics in Advanced practice Nursing Journal ,7,4.
  68. 68.  Academy of Medical Surgical Nurse, Evidence-based practice module 1,2 (power point) Glover ,J. Izzo, D.,Odato, K.,Wang, L. (2006) EBM Pyramid . Yale University School of Medicine. tml