The effects of recall errors and of selection bias in epidemiologic studies of mobile phone use and cancer risk
1: J Expo Sci Environ Epidemiol. 2006 Jun 14; [Epub ahead of print]
Vrijheid M, Deltour I, Krewski D, Sanchez M, Cardis E.
International Agency for Research on Cancer, Lyon, France.
This paper examines the effects of systematic and random errors in recall and of selection bias in case-control studies of mobile phone use and cancer. These sensitivity analyses are based on Monte-Carlo computer simulations and were carried out within the INTERPHONE Study, an international collaborative case-control study in 13 countries. Recall error scenarios simulated plausible values of random and systematic, non-differential and differential recall errors in amount of mobile phone use reported by study subjects. Plausible values for the recall error were obtained from validation studies. Selection bias scenarios assumed varying selection probabilities for cases and controls, mobile phone users, and non-users. Where possible these selection probabilities were based on existing information from non-respondents in INTERPHONE. Simulations used exposure distributions based on existing INTERPHONE data and assumed varying levels of the true risk of brain cancer related to mobile phone use. Results suggest that random recall errors of plausible levels can lead to a large underestimation in the risk of brain cancer associated with mobile phone use. Random errors were found to have larger impact than plausible systematic errors. Differential errors in recall had very little additional impact in the presence of large random errors. Selection bias resulting from underselection of unexposed controls led to J-shaped exposure-response patterns, with risk apparently decreasing at low to moderate exposure levels. The present results, in conjunction with those of the validation studies conducted within the INTERPHONE study, will play an important role in the interpretation of existing and future case-control studies of mobile phone use and cancer risk, including the INTERPHONE study.Journal of Exposure Science and Environmental Epidemiology advance online publication, 14 June 2006; doi:10.1038/sj.jes.7500509.
PMID: 16773122 [PubMed - as supplied by publisher]
http://tinyurl.com/lklkv
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Do I read this right:
"Results suggest that random recall errors of plausible levels can lead to a large underestimation in the risk of brain cancer associated with mobile phone use."
Isn't that exactly what we were told by Hepworth, Shoemaker ... Swerdlow et al., "Mobile phone use and risk of glioma in adults: case-control study"?:
"The complementary positive and negative risks associated with ipsilateral and contralateral use of the phone in relation to the side of the tumour might be due to recall bias."
http://press.psprings.co.uk/bmj/january/glioma.pdf
Omega see also "Mobile phone use and risk of glioma in adults" under: http://omega.twoday.net/stories/1439856/
Hmmm.
Andy
From Mast Sanity/Mast Network
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INTERPHONE
One remark on the Interphone: Choosing the biased definition of regular user in the INTERPHONE is not a "Random error" at all. It is made with an intention. Why don't researchers of tobacco define someone who smokes 1 cigarette a week as "a regular smoker"? Because they are not ready to make a fool of themselves when writing in the conclusions that "regular smokers" didn't have an increased risk for lung cancer. People laugh very loud when I tell them about the definition of the regular user in the INTERPHONE. They immediately get the point and the purpose of the study. I am talking about non- scientific people. It is misleading and not honest to use this definion and then to write at the conclusions (like in the Interphone german study for example) that there was no increased risk for regular users, while the definition itself does not represent regular users at all. Hardell's study is several levels above the INTERPHONE study because Hardell's research is scientific, whereas the INTERPHONE is a political study. After I saw IARC'S Philip Autier saying that dioxin is not carcinogenic for humans while it is on the IARC list of known carcinogens from 1997, I have to think - something is very rotten at IARC and you'd bettter believe it.
Iris Atzmon
--------
http://omega.twoday.net/search?q=brain+cancer
http://omega.twoday.net/search?q=cancer+risk
Vrijheid M, Deltour I, Krewski D, Sanchez M, Cardis E.
International Agency for Research on Cancer, Lyon, France.
This paper examines the effects of systematic and random errors in recall and of selection bias in case-control studies of mobile phone use and cancer. These sensitivity analyses are based on Monte-Carlo computer simulations and were carried out within the INTERPHONE Study, an international collaborative case-control study in 13 countries. Recall error scenarios simulated plausible values of random and systematic, non-differential and differential recall errors in amount of mobile phone use reported by study subjects. Plausible values for the recall error were obtained from validation studies. Selection bias scenarios assumed varying selection probabilities for cases and controls, mobile phone users, and non-users. Where possible these selection probabilities were based on existing information from non-respondents in INTERPHONE. Simulations used exposure distributions based on existing INTERPHONE data and assumed varying levels of the true risk of brain cancer related to mobile phone use. Results suggest that random recall errors of plausible levels can lead to a large underestimation in the risk of brain cancer associated with mobile phone use. Random errors were found to have larger impact than plausible systematic errors. Differential errors in recall had very little additional impact in the presence of large random errors. Selection bias resulting from underselection of unexposed controls led to J-shaped exposure-response patterns, with risk apparently decreasing at low to moderate exposure levels. The present results, in conjunction with those of the validation studies conducted within the INTERPHONE study, will play an important role in the interpretation of existing and future case-control studies of mobile phone use and cancer risk, including the INTERPHONE study.Journal of Exposure Science and Environmental Epidemiology advance online publication, 14 June 2006; doi:10.1038/sj.jes.7500509.
PMID: 16773122 [PubMed - as supplied by publisher]
http://tinyurl.com/lklkv
--------
Do I read this right:
"Results suggest that random recall errors of plausible levels can lead to a large underestimation in the risk of brain cancer associated with mobile phone use."
Isn't that exactly what we were told by Hepworth, Shoemaker ... Swerdlow et al., "Mobile phone use and risk of glioma in adults: case-control study"?:
"The complementary positive and negative risks associated with ipsilateral and contralateral use of the phone in relation to the side of the tumour might be due to recall bias."
http://press.psprings.co.uk/bmj/january/glioma.pdf
Omega see also "Mobile phone use and risk of glioma in adults" under: http://omega.twoday.net/stories/1439856/
Hmmm.
Andy
From Mast Sanity/Mast Network
--------
INTERPHONE
One remark on the Interphone: Choosing the biased definition of regular user in the INTERPHONE is not a "Random error" at all. It is made with an intention. Why don't researchers of tobacco define someone who smokes 1 cigarette a week as "a regular smoker"? Because they are not ready to make a fool of themselves when writing in the conclusions that "regular smokers" didn't have an increased risk for lung cancer. People laugh very loud when I tell them about the definition of the regular user in the INTERPHONE. They immediately get the point and the purpose of the study. I am talking about non- scientific people. It is misleading and not honest to use this definion and then to write at the conclusions (like in the Interphone german study for example) that there was no increased risk for regular users, while the definition itself does not represent regular users at all. Hardell's study is several levels above the INTERPHONE study because Hardell's research is scientific, whereas the INTERPHONE is a political study. After I saw IARC'S Philip Autier saying that dioxin is not carcinogenic for humans while it is on the IARC list of known carcinogens from 1997, I have to think - something is very rotten at IARC and you'd bettter believe it.
Iris Atzmon
--------
http://omega.twoday.net/search?q=brain+cancer
http://omega.twoday.net/search?q=cancer+risk
Starmail - 25. Jun, 17:26
