Misleading communication aid

The systematic review comparing various osteoarthritis treatment options is a valuable summary of the evidence and I thank the authors for their work.¹

Unfortunately the simplified decision aid with the page of 100-face diagrams is misleading and does not accurately and clearly summarize the evidence collected.² Meaningfully improved pain is not defined in the article so it is not clear exactly what is being measured in the diagrams. It looks as though 94% of the patients to whom I prescribe exercise will have improvement (54% of them owing to the exercise and 40% related to natural variation in disease severity). This leaves only 6% who will get worse or stay the same. One has to read the text in detail to discover the statistical compromises that resulted in this implausible finding.

The accompanying table lists opioids as being likely harmful, but the 100-face diagram makes them look modestly beneficial. Only the text makes it clear that this is because the diagram represents short-term outcomes and the table focuses on long-term outcomes (which is appropriate for a chronic disease).

Glucosamine, chondroitin, and viscosupplementation appear twice on the page of 100-face diagrams, but only the text explains that the benefits are unclear because industry-funded trials with positive results could not be replicated.

I am glad that I read the whole article and it will help me with quantifying benefits when sharing decision making with my patients, but I will definitely not be using the 100-face diagram as a communication aid. It is not a good summary of the evidence so carefully collected in the systematic review.

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