Sense about Science ? equipping people to make sense of science and evidence
For the record
Exposure to mobile phones before and after birth linked to behavioural problems in children
On 6th December several newspapers (including Daily Mail, The Sun, Metro and The Telegraph) reported showing a ‘link’ between mobile phones use by expectant mothers and also their children and behavioural problems in their children. The research was published in the Journal of Epidemiology and Community Health. Many of the media stories put the research into context with quotes from other scientists explaining why the ‘link’ reported in the epidemiological study did not show that mobile phone exposure causes behavioural problems and that other factors need to be considered.
It is a pity to see that the press release by the BMJ, entitled “Exposure to mobile phones before and after birth linked to kids' behavioral problems”, did not explain that the research does not show that mobile phone exposure causes behavioural problems apart from a brief quote at the end. In the last sentence the researchers say: “although it is premature to interpret these results as causal, we are concerned that early exposure to cell phones could carry a risk, which, if real, would be of public health concern given the widespread use of this technology." Also, the press release did not discuss other factors that might have affected the results.
The comments below from other scientists not involved in the study explain the limits of the research presented in this paper:
Prof David Coggon, Professor of Occupational and Environmental Medicine at the University of Southampton, said:
"This study appears to have been well conducted, but the pattern of results suggests that the observed increase in behavioural problems may have been caused by factors other than mobile phone use. When the authors took into account considerations such as quality of parenting, estimates of risk were reduced, but confounding influences of this sort are unlikely to have been fully eliminated."
Prof David Spiegelhalter, Professor of Biostatistics at the University of Cambridge, said:
“I am sceptical of these results, even though they will get a lot of publicity. One finding is that very young children who use mobile phones show more behavioural disorders: this may well be the case, but is it plausible that the first causes the second? The authors suggest that precautionary measures may be warranted because they have ‘virtually no cost’, but they ignore the cost of giving intrusive health advice based on inadequate science."
"The authors say that 'early exposure to cell phones could carry a risk which, if real, would be of public health concern'. Well, I might just as well say 'Paul's psychic abilities, if real, would revolutionise our thinking about molluscs.'"
Cell phone use and behavioural problems in young children, Hozefa A Divan, Leeka Kheifets, Carsten Obel and Jorn Olsen, J Epidemiol Community Health (2010) doi 10.1136/jech.2010.115402
Author: Sense About Science
Document type: For The Record
Published: 9 December 2010