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  1. To introduce and practice interpreting key statistical concepts
  2. To help participants plan messaging for potential outcomes of future trials
  3. To provide participants with the skills to communicate trials results
  4. To help participants understand the concept of media bias, and how to recognize it

Key points

  • Although statistical analyses can be complex, understanding them is essential to proper interpretation of clinical trial results
  • It is important to be prepared with potential messages prior to learning the results of a trial
  • The same trial results can lead to many different interpretations—it is important to recognize media biases so that we can better understand why a particular analysis is being provided

Suggested activities

Practicing interpreting statistics (slide 14)

Part 1:
When slide opens, just the efficacy stat with CI and p‐value appears. Have the participants explain in their own words each component of the stats: 1) the efficacy; 2) the confidence interval; and 3) the p‐ value. Then, click on the slide so that the accurate interpretations appear.

  • “The vaccine recipients had a 31% lower risk of HIV infection than those who received placebo.”
  • “The efficacy of the prime‐boost regimen could be anywhere in the range of 1.2% to 52.1%, yet the most likely efficacy is at the middle of that range, or 31.2%.”
  • “If the vaccine had no effect whatsoever, there is a 4% chance that this split in infections, or an even larger one, would have occurred anyway.”

Part 2:
Distribute the Statistics Worksheet and have participants practice translating the numbers into sentences (#1 of the worksheet is completed as a group in Part 1 of this exercise).

You can also distribute the Glossary of Key Statistical Terms to help participants with this activity and with understanding statistics after the workshop.
Discussion (Slide 23)

Before putting up this slide, have participants list key messages that should be delivered regardless of a trial outcome. You can then put up the slide and discuss the messages listed:

  1. Prevention efforts must continue
  2. Research must continue
  3. Much has been learned to advance further research
  4. [Our country] must prepare for eventual availability of NPTs
  5. The safety and well‐being of trial participants remains the top priority for researchers

Alternatively, if you have time, you can divide the participants into 4 groups and assign each group one of the slides from 19‐22. Ask them to come up with key messages that should be delivered for their trial outcome. Then facilitate a discussion of key messages that should be delivered regardless of a trial outcome.
Exercise: CAPRISA microbicide trial (slide 25)

Divide participants into small groups; each receives the CAPRISA 004 trial backgrounder. Have each group review the document and discuss:

  • What was the result of the trial?
  • Summarize the trial findings into one PowerPoint slide or 50‐word summary

In plenary discussion, ask participants to share their summaries, and discuss any difficulties they encountered in interpreting the results.
Exercise: Media analysis (slide 28)

Make copies of newspaper articles that appeared concerning the CAPRISA trial. Articles from the Sowetan (South Africa), Vanguard (Nigeria) and Toronto Star (Canada) are included on the CD as examples. Have participants take a few minutes to read the articles carefully and consider the key concepts in the previous slide as well as the factual information they know from the previous exercise (review of backgrounder). Then discuss in plenary some of the following questions:

  • How accurate is the media coverage of the trial results?
  • What biases (if any) do you detect?
  • What seem to be the sources for the article?
  • What is the overall tone of the article?
  • What do you think the impact of the article might be in the community?
  • How does the article’s content and tone compare to what you think should be conveyed to the community?
  • How does the summary you prepared in the previous exercise compare to the key message from this article?

Exercise: Media analysis (part 2) (slide 29)

Hand out copies of the TAC response to the Sowetan article, then discuss in plenary some of the following questions:

  • What do you think of TAC’s response?
  • Did they address the same concerns you had when you read the Sowetan article?
  • Were any elements missing?
  • Are there any consequences—good or bad—to responding like this?
  • Would you have responded? In a similar way? Differently?