Academics are questioning whether Australian cardiology guidelines can be trusted after finding that up to 60% of the authors have undisclosed links with industry.
A review of 33 NHMRC-endorsed clinical guidelines – including four covering cardiovascular conditions – found that only 14% of guideline authors disclosed any financial conflicts of interest.
But one in four of the authors who did not disclose any financial interests were found by Bond University researchers to have at least one potentially relevant undisclosed financial tie to a pharmaceutical company active in the therapeutic area.
Of the four clinical guidelines covering cardiology, one had 59% of authors with undisclosed ties to industry, while the others had 50%, 43% and 29% of authors with undisclosed ties.
Overall, more than two-thirds, or 70%, of the 33 guidelines in their sample had at least one writer with an undisclosed tie
In their study in BMJ Open, the researchers also showed that guidelines developed by government were much less likely to have authors with potential biases than guidelines developed by non-government groups such as colleges and professional bodies (8% of authors compared with 31%). And guidelines for specialties such as arthritis, diabetes and cardiovascular disease were more likely to have undisclosed conflicts of interests than others such as mental health and injury.
They added that their findings were likely to underestimate the true scale of undisclosed conflicts of interest because the guidelines were published at a time when there was no open reporting of financial links between clinicians and industry.
“Guideline writer ties to companies with interest in the guideline’s outcome raise critical questions about potential bias in processes that may have great impacts on the use of healthcare interventions,” they commented.
“These data confirm the need for strategies to ensure greater transparency and more independence in relationships between guidelines and industry, they concluded.
The study authors added that it was not unrealistic to expect guidelines to be produced by independent authors.
“Almost one in five of these guidelines had less than 10% of writers with any ties to industry [showing] it is possible to assemble guideline panels almost entirely free of financial conflicts of interest,” they said.
The NHMRC is now working on a new guideline development framework that will include more rigorous requirements about identifying and managing conflicts of interest of authors.