Gert van der Hoek
In Memoriam - Editor, Senior Moderator
October 25, 2011
CDC's new estimate of flu vaccine efficacy: 50-70% in healthy adults... A risk communication comment
Brief analysis of a risk communication error:
The CDC reports its newest estimate of influenza vaccine efficacy:
50-70% in healthy adults under 65
By Jody Lanard M.D. (posted on October 25 2011, 1:30 pm EDT)
On October 12, the U.S. CDC updated its estimate of influenza vaccine effectiveness (written for health care professionals), based on randomized controlled studies published in 2009 and early 2010.
The most notable datum in the update:
Flu Vaccine Effectiveness: Questions and Answers for Health Professionals (October 12 2011)
>How well do inactivated influenza vaccines work in randomized control trials?
>As noted above, effectiveness varies with vaccine match and the age and immune function of the recipient. In general, the greatest benefits of influenza vaccines have been reported in randomized controlled trials (RCTs) conducted among healthy adults. For example, recent RCTs of inactivated influenza vaccine among adults under 65 years of age have estimated 50-70% vaccine efficacy during seasons in which the vaccines' influenza A components were well matched to circulating influenza A viruses (Beran et al., 2009, 2006-2007 season; Jackson et al., 2010, 2005-2006 season; Monto et al., 2009, 2007-2008 season). As vaccine efficacy from a randomized clinical trial is the gold standard for how well a vaccine actually works, vaccine effectiveness estimates obtained from observational studies can equal, but not exceed, estimates of efficacy.<
This updates the CDC’s previous estimate of 70% to 90% efficacy, based on older studies.
Here's the risk communication error:
The October 12 2011 update does not mention the previous estimate, or highlight that “50-70%” in healthy adults under 65 is a rather dramatic downward change. The update only notes that the estimate is based on “recent RCTs”.
And the CDC did not issue a heads-up to journalists highlighting the new, much lower estimate of efficacy.
As of noon on October 25th, no medical or other journalists appear to have reported this new information.
Read more - Riskcommunication
thanks to Crawford Killian for the link
CDC's new estimate of flu vaccine efficacy: 50-70% in healthy adults... A risk communication comment
Brief analysis of a risk communication error:
The CDC reports its newest estimate of influenza vaccine efficacy:
50-70% in healthy adults under 65
By Jody Lanard M.D. (posted on October 25 2011, 1:30 pm EDT)
On October 12, the U.S. CDC updated its estimate of influenza vaccine effectiveness (written for health care professionals), based on randomized controlled studies published in 2009 and early 2010.
The most notable datum in the update:
Flu Vaccine Effectiveness: Questions and Answers for Health Professionals (October 12 2011)
>How well do inactivated influenza vaccines work in randomized control trials?
>As noted above, effectiveness varies with vaccine match and the age and immune function of the recipient. In general, the greatest benefits of influenza vaccines have been reported in randomized controlled trials (RCTs) conducted among healthy adults. For example, recent RCTs of inactivated influenza vaccine among adults under 65 years of age have estimated 50-70% vaccine efficacy during seasons in which the vaccines' influenza A components were well matched to circulating influenza A viruses (Beran et al., 2009, 2006-2007 season; Jackson et al., 2010, 2005-2006 season; Monto et al., 2009, 2007-2008 season). As vaccine efficacy from a randomized clinical trial is the gold standard for how well a vaccine actually works, vaccine effectiveness estimates obtained from observational studies can equal, but not exceed, estimates of efficacy.<
This updates the CDC’s previous estimate of 70% to 90% efficacy, based on older studies.
Here's the risk communication error:
The October 12 2011 update does not mention the previous estimate, or highlight that “50-70%” in healthy adults under 65 is a rather dramatic downward change. The update only notes that the estimate is based on “recent RCTs”.
And the CDC did not issue a heads-up to journalists highlighting the new, much lower estimate of efficacy.
As of noon on October 25th, no medical or other journalists appear to have reported this new information.
Read more - Riskcommunication
thanks to Crawford Killian for the link