Fact or fallacy? Immunisation arguments in the New Zealand print media

Objective: To explore New Zealand's four major daily newspapers' coverage of immunisation with regards to errors of fact and fallacy in construction of immunisation-related arguments. Methods: All articles from 2002 to 2007 were assessed for errors of fact and logic. Fact was defined as that which was supported by the most current evidence-based medical literature. Errors of logic were assessed using a classical taxonomy broadly based in Aristotle's classifications. Results: Numerous errors of both fact and logic were identified, predominantly used by anti-immunisation proponents, but occasionally by health authorities. The proportion of media articles reporting exclusively fact changes over time during the life of a vaccine where new vaccines incur little fallacious reporting and established vaccines generate inaccurate claims. Fallacious arguments can be deconstructed and classified into a classical taxonomy including non sequitur and argumentum ad Hominem. Conclusion: Most media 'balance' given to immunisation relies on 'he said, she said' arguments using quotes from opposing spokespersons with a failure to verify the scientific validity of both the material and the source. Implications: Health professionals and media need training so that recognising and critiquing public health arguments becomes accepted practice: Stronger public relations strategies should challenge poor quality articles to journalists' code of ethics and the health sector needs to be proactive in predicting and pre-empting the expected responses to introduction of new public health initiatives such as a new vaccine.