Guidelines With Global Implications

1. Guidelines With Global Implications Robert West, PhD

2. Outline • Need for a global evidence base • Aims and methods • Examples of evidence statements • Conclusions

3. Need for Global Evidence Base • Guideline development is an ongoing process worldwide • Repeating evidence reviews in each case is potentially wasteful, error-prone, and a source of inconsistencies • Guidelines themselves must take account of local circumstances, but the global evidence baseis generalisable

4. Aim • To present up-to-date, top-line conclusions on efficacy and effect size estimates of major clinical smoking-cessation interventions, together with caveats and qualifications, using a consistent format that can be used to calculate the cost-effectiveness of these interventions in preventing morbidity and mortality

5. Methods • Evidence base • Cochrane Reviews supplemented by individual studies to provide caveats and qualifications or to utilize when Cochrane Reviews are not available • Effect size estimate • 6-month continuous abstinence rate • Divide by 2 to get effect on “permanent cessation” • Basis of effect size estimate • “Russell Standard” where possible (West et al. 2005)

6. Clear Evidence • When given to [population category],[intervention category] has been found in [type of study/analysis]to increase 6-month abstinence rates by [range of values/NT range] compared with [comparator]

7. Suggestive Evidence • When given to [population category], evidence from [type of study/analysis]suggests that[intervention category] increases 6-month abstinence rates by [range of values] compared with [comparator]

8. Inconsistent Evidence • Evidence from [type of study/analysis] is inconsistent on the effectiveness of [intervention category] compared with [comparator]

9. Negative Evidence • Adequately powered and designed studies have failed to find an effect of [intervention category] compared with [comparator]

10. Insufficient Evidence • Insufficient evidence is available from which to draw conclusions about/regarding [statement concerning intervention category]

11. Caveats and Qualifications • Factors that may limit generalisability • Additional comparisons • Observational evidence of effectiveness intoreal-world settings

12. Brief Advice: Evidence Statement • Brief opportunistic advice involves a health professional raising the topic of smoking with a patient, advising the patient to stop, and offering support and follow-up • When given to unselected smokers attending a consultation for some other condition, brief advice has been found in multiple randomised controlled trials to increase 6-month abstinence rates by an average of 1% to 3% over a baseline quit rate of 3% (NNT=33-100) compared with doing nothing

13. Brief Advice: Caveats and Qualifications 1 • There is insufficient evidence to draw firm conclusions regarding the optimal manner in which the advice is given, and in any event this advice may vary according to the prevailing culture. Some guidelines have suggested an approach based on the “5 A’s”: Ask, Advise, Assess, Assist, Arrange. However, no evidence suggests that such an approach is more effective than one that, for example, asks about smoking and at the same time offers helpwith stopping • There is insufficient information to draw conclusions about whether this type of advice given by health professionals who are not physicians is effective

14. Brief Advice: Caveats and Qualifications 2 • The studies to date have mostly been carried out in a context in which medication and specialist behavioural support to aid cessation were not available. Encouraging smokers to use these treatments may increase the net effect of opportunistic advice • The studies were carried out in a context in which few other environmental factors promoting smoking cessation were present in the population (eg, indoor smoking restrictions). The effect in other contexts may vary • Brief opportunistic advice appears to have its effect by triggering a quit attempt. Whether quit attempts triggered in this way are more likely to be successful than quit attempts triggered in other ways is not known

15. Behavioural Support:Evidence Statements • Behavioural support involves providing advice and encouragement and sometimes practical exercises designed to bolster and sustain motivation to remain abstinent and minimize motivation to smoke during a quit attempt • When given to smokers seeking help with stopping, behavioural support has been found in multiple randomised controlled trials to increase 6-month continuous abstinence rates by 3% to 7% (NNT=14-33) compared with a control group quit rate of 5% for patients trying to quit but not receiving face-to-face support, only written materials, or brief advice

16. Behavioural Support: Caveats and Qualifications 1 • The studies conducted to date have usually involved multiple sessions provided by specially trained health professionals over a period of 1 to more than 4 weeks after a clearly specified target quit date. Single sessions of support or support provided by individuals who have not been specially trained or who are mainly employed on other duties and have to fit the behavioural support into those duties do not have clear evidence of effectiveness • The support can be provided to groups of smokers or individual smokers face to face or by telephone. Insufficient evidence is available from which to draw firm conclusions about whether any of these modes of delivery are likely to be more effective than others • Adding scheduled sessions of telephone support to face-to-face support has been found in multiple randomized controlled trials to increase 6-month continuous abstinence rates by 2% to 3% (NNT=33-50)

17. Behavioural Support: Caveats and Qualifications 2 • Insufficient evidence is available from which to draw conclusions about whether different approaches to behavioural support are more effective than others. Specifically, whether “cognitive behavioural therapy” or “motivational interviewing” is more effective than support not based on any particular theoretical position is not known • Insufficient evidence is available from which to draw conclusions about whether behavioural support is effective for long-term cessation, specifically in patients awaiting surgery • When given to hospital inpatients, behavioural support only appearsto be effective in promoting long-term smoking cessation if it continues for at least 1 month after discharge • Adequately powered and designed studies have failed to find an effect of relapse-prevention sessions after the initial acute withdrawal period (usually 4 weeks) compared with no additional intervention

18. Conclusions • A need exists for a global evidence base for use in treatment guidelines with findings expressed in a consistent format that can be used to determine cost-effectiveness • The current review uses the most rigorous available reviews supplemented by additional studies to • Provide quantitative effect size estimates • List caveats and qualifications that are important in interpreting these estimates