Tuesday 6 August 2013

Warning: Distressing content which may damage you


What possessed you to read this item? Do you really think you can handle it? It might cause you permanent distress and unhappiness, even illness. For example, the sort of problems you might get if you exposed yourself to media coverage of dreadful events, like terrorist atrocities and wars. You know what I mean. Stuff you see on TV, without switching it off. Stuff you continue to watch, even when the announcer says that some of the content is distressing or “might disturb some viewers”. By the way, it is not too late to give up reading this item.


Mental- and Physical-Health Effects of Acute Exposure to Media Images of the
September 11, 2001, Attacks and the Iraq War. Silver, Holman, Andersen, Poulin, McIntosh, and Gil-Rivas. Psychological Science OnlineFirst, published on August 1, 2013 as doi:10.1177/0956797612460406

Silver et al. have done a study on a perfectly reasonable sample, and here is their abstract:

Millions of people witnessed early, repeated television coverage of the September 11 (9/11), 2001, terrorist attacks and were subsequently exposed to graphic media images of the Iraq War. In the present study, we examined psychological and
physical-health impacts of exposure to these collective traumas. A U.S. national sample (N = 2,189) completed Web-based surveys 1 to 3 weeks after 9/11; a subsample (n = 1,322) also completed surveys at the initiation of theIraq War. These surveys measured media exposure and acute stress responses. Posttraumatic stress symptoms related to 9/11 and physician-diagnosed health ailments were assessed annually for 3 years. Early 9/11- and Iraq War–related television exposure and frequency of exposure to war images predicted increased posttraumatic stress symptoms 2 to 3 years after 9/11. Exposure to 4 or more hr daily of early 9/11-related television and cumulative acute stress predicted increased incidence of health ailments 2 to 3 years later. These findings suggest that exposure to graphic media images may result in physical and psychological effects previously assumed to require direct trauma exposure.

In fact, there is a previous clinical literature showing that TV can trigger disturbances which meet the diagnostic criteria for PTSD. The authors list some of the other papers showing a “ptsd by TV” effect.That aside, they have a sizeable and nationally representative sample, so the usual problems of self selected clinical samples do not apply.

What strikes you most about the abstract? To my eyes the key phrase is “Exposure to 4 or more hours daily of early 9/11-related coverage and cumulative acute stress predicted increased incidence of health ailments 2 to 3 years later”. Four or more hours daily of television about a dreadful event is a lot of television viewing. One day might be understandable. Who would do such a thing for several days? One should distinguish between an early acute phase in which most citizens take in the event itself, and the new hazard it represents, and another longer phase in which most citizens stop watching disaster coverage and have returned to their lives, still with the additional threat in mind to some degree. Finding out about bad things is part of reality, and assists in the planning of avoidance and coping reactions. Repeating exposure to tragedy is unlikely to help planning of any sort.

Looking at the paper itself, it is immediately apparent that the stress estimates are based on self-report. These need not be totally inaccurate, but they are hardly conclusive. Studying a sub-sample with a telephone or face to face interview would have been more convincing. On a more general methodological point, the more anxious “vigilant” danger-signal-seeking persons (the sort who might watch lots of frightening news coverage) might be more likely to have anxiety responses, be anxious about their health, and consult a physician about their health. The authors controlled for pre-exposure mental health issues, so they have a partial corrective, but they do not have, or do not use, personality data which could be highly relevant in this context. The odds ratio of distress for those with pre-9/11 mental-health ailments was 1.37 [1.20, 1.56] < .001. The odds ratio for those watching more than 4 hours per day of 9/11-related TV in the week after 9/11 was 1.57 [1.15, 2.14] .004  The sex odds ratio was 1.49. As usual, women were more vulnerable.

I think that the simplest explanation is that pre-event mental health problems made people more vulnerable, and extensive self-exposure to TV about the event made them even more vulnerable. Perhaps the abstract should have read:

These findings suggest that prior vulnerabilities plus self exposure to graphic media images may result in physical and psychological self-reported effects, more so in women.

Not quite so stirring a finding when you put in these explanations, is it?

I think that when research relies on well-standardised samples of respondents it would strengthen analysis of causal factors if these respondents have been tested for personality and intelligence, both well known to be important factors in PTSD vulnerability and other illness behaviours.

Meanwhile, if you find that your health deteriorates after reading this little item, you have only yourself to blame. You ignored a clear warning. You are on your own.


  1. "mental health issues": eh? What's that in English? Do they mean that they were a bit bonkers already?

  2. "ailments" is a fine word. Thank you.