CLINICAL EFFICACY: KNOWING WHAT WORKS

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CLINICAL EFFICACY KNOWING WHAT WORKS

• Laura Bolton, PhD, FAPWCA
• Adj. Assoc. Professor  Department of Surgery
  (Bioengineering)
• UMDNJ, New Brunswick, NJ

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Rationale

•  Clinicians use evidence to supplement clinical
  judgment to improve
• Consistency and quality of care
• Patient and wound outcomes
• Clear scientific method proves efficacy
• Misuse of the term efficacy confuses all
• More accurate efficacy communication helps
• Professionals support and implement care
  decisions
• Patients receive care that works
• Institutions deliver consistent high quality care

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Educational Objectives Of this Literature Review

• Define wound care efficacy
• Locate evidence of efficacy
• Recognize good quality efficacy evidence
• List example aspects of chronic wound care with
  sound evidence of efficacy

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Methods

• Study Design Literature review
• Procedure
• Literature search of MEDLINE, Cochrane, AHRQ, and
  Google databases for terms
• definition clinical (or wound) efficacy
• clinical (or wound) evidence source
• strength of evidence and evidence criteria
• improve wound care outcomes.
• Included references on efficacy
• Excluded those on safety only

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Efficacy Evidence defined1

• That which proves or disproves something
• ground for belief
• proof
• 1RWebsters College Dictionary, Random House,
  McGraw-Hill Edition, 1976

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Definitions of Efficacy in Health Care

• AHRQ1 Whether a drug or other treatment works
  under the best possible conditions
• Study participants carefully selected May
  differ from general public who have the disease
• Agent applied and stored properly.
• Treatment with efficacy under best conditions
  may not work as well in a different group with
  same disease.
• FDA2 A properly conducted randomized controlled
  trial (RCT) compares test intervention to a
  standard of care as proof of its comparative
  efficacy.
• IOM3 Efficacy RCTs answer Does Agent A work?
• Effectiveness trials answer Is A better than B
  in practice?

1. www.effectivehealthcare.ahrq.gov/index.cfm/glossar
   y-of-terms/
2. www.fda.gov/cder/guidance/ 5512/fnl.pdf Accessed
   May 1, 2009
3. www.annals.org/content/151/3/203.full Accessed
   April 2, 2010

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AHRQ Criteria for Distinguishing Between Efficacy
and Effectiveness (sensitivity 0.83 specificity
0.721
Criterion Efficacy Effectiveness
Population studied In larger, more equipped, specialized care settings Local available care for diverse populations
Eligibility criteria More stringent, highly selected Less stringent, more general
Outcomes studied Objective or subjective symptoms or lab results Clinically relevant health-related outcomes
Study duration and treatment Sufficient to prove effect safety strict adherence to protocol Sufficent to measure the outcomes in everyday use
Adverse event assessment All related and unrelated adverse events reported Limited to critical issues from prior studies
Sample size Large enough to prove the modality works and is safe Large enough to detect a minimally important quality of life difference
Intent-to-treat analysis Efficacy excludes subjects with protocol deviations Analyzes all subjects enrolled into treatment
Gartlehner G, et al. AHRQ Publication No.
06-0046. Rockville, MD Agency for Healthcare
Research and Quality. April 2006
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Results Mining the treasure that proves
efficacy http//.

• Cochrane Initiative Systematic reviews, reports
• www.cochrane.org/
• Joanna Briggs Initiative Best practice summaries
• joannabriggs.www.edu.au/pubs/best_practice.php
• Core Library of Evidence Based Practice Articles
• http//74.125.93.132/search?qcacheO-z76YXoSKYJ
  www.shef.ac.uk/scharr/ir/core.htmlUKevidence
• Agency for Healthcare ResearchQuality
  Initiatives
• www.ahrq.gov/clinic/epcix.htm
• National Library of Med. (MEDLINE) Abstracts
• www.ncbi.nlm.nih.gov/PubMed/
• National Guideline Clearinghouse Guidelines
• www.guideline.gov/
• Clinical trials clinicaltrials.gov

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Results Recognizing efficacy evidence that is
treasure to improve patient outcomes1,2

• Treatment effects compared to
• Consistent best practice standard
• Well-blinded sham or placebo control
• Patients assigned randomly to treatment
• Independent blinded comparison
• Efficacy and safety measured and reported
• Valid outcomes measured reliably
• Clinically relevant, patient-centered
• Representative, relevant patient samples
• Adequate timing and scope of follow up
• 1Jaeschke R et al. Adv Wound Care, 1998
  11(5)214-218
• 2Van Rijswijk L. Pediatric Nursing, 1990
  2(3)158-161.

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Results Grading Efficacy EvidenceMore detail
at AHRQ Website http//www.ahrq.gov/clinic/epcsu
ms/strengthsum.htm
RCTs SR, MA
Convenience or Historical Controlled CT Or
Relevant Animal CT
Case Controlled Studies, Case Studies,
Uncontrolled Models (Usually in vivo gt in vitro)
Systematically Validated Opinion Consensus
Statement Individual Opinion
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Results Wielding Efficacy Evidence

• Use of current best evidence to inform decisions
  about the care of an individual patient.1

1Sackett DL et al. Br Med J, 1997 31271-77.
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ResultsEvidence Quality and How to Use It

• Opinion or consensus of opinion
• Observation or description
• Measured observation
• " on defined set of patients
• " on " given standard practice
• " on " comparing gt1 standard "
• " on " " randomly assigned "
• See also Meakins J. Amer J Surgery 2002183399
• Gray M. et al. JWOCN 2004 31(2)53-61.

LOW
Generate Research Support Practice
HIGH
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Conclusions Example Steps with Efficacy in
Chronic Wound Management Pressure Ulcers1-4

• Address causes of tissue damage
• prolonged pressure, friction, sheer1-4
• nutritional deficiencies1-4
• Wound bed
• Debride necrotic tissue4
• Treat local or distant infection2
• Protect skin from
• excess moisture or dryness1,3,4
• chemical or physical trauma1,3,4
• Maintain a moist wound environment1-4

Pressure ulcer treatment prevention guidelines
AHRQ,1 WHS2 and WOCN3 4Kerstein et al. Disease
Management Health Outcomes, 2001 9(11)651-663
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Conclusions continuedSteps with Venous Ulcer
Management Efficacy1,2,3

• Diagnose and correct the cause
• Rule out arterial cause
• Ankle/brachial index (ABI) gt 0.9
• ABI 0.7-0.9 compress with care
• Sustained, graduated, high, 2- to 4- layer
  elastic compression
• Elevate limb, flex ankle or walk
• Elastic stockings prevent recurrence
• Manage exudate and dermatitis
• Moist wound environment4

Pressure ulcer treatment prevention guidelines
AAWC,1 WHS2 and WOCN3 4Kerstein et al. Disease
Management Health Outcomes, 2001 9(11)651-663
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Conclusions, continued Steps with Arterial
Ulcer Management Efficacy1,2

• Diagnose, correct related conditions1,2
• Peri-wound TcPO2 lt 20 mmHg predicts non-healing1
• Vascular specialist locate, correct arterial
  blockage
• Prompt referral if rest pain and/or gangrene2
• Remove necrotic tissue
• limit microorganisms2
• Avoid nicotine1,2

1Hopf H. et al. Wound Rep Regen, 2006 14
693-710. (WHS Guideline) 2Kerstein MD.
Ostomy/Wound Mgmt 1996 42(10A Suppl)19S-35S
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Conclusions, continued Steps with Diabetic
Foot Ulcer Care Efficacy1,2,3,4

• Diagnose and correct the cause
• Control diabetes (HbA1c lt 6.5)
• ABI gt 0.9 rules out arterial insufficiency
• ABI gt 1.3 ? rigid vessel wall use great toe
• No ABI, use TcPO2 gt 40 mmHg
• Check for neuropathy
• Semmes-Weinstein 10 g (5.07) fiber
• Protect skin and off load consistently
• Wound/Skin
• Gel debridement speeds DFU healing4
• No healing progress suspect infection
• Moist wound environment3

1Steed et al. Wound Rep Reg (2006) 14 680692
(WHS Guideline) 2Crawford et al. WOCN Guideline 3
Lower extremity neuropathic disease 3Boulton et
al. Wound Rep Reg 199977-16 42Smith J, Thow
J. The Diabetic Foot 2003 6(1)12-16