Effects of Recall and Selection Biases on Modeling Cancer Risk From Mobile Phone Use: Results From a Case-Control Simulation Study.

Background: The largest case-control study (Interphone study) investigating glioma risk related to mobile phone use showed a J-shaped relationship with reduced relative risks for moderate use and a 40% increased relative risk among the 10% heaviest regular mobile phone users, using a categorical risk model based on deciles of lifetime duration of use among ever regular users.
Methods: We conducted Monte Carlo simulations examining whether the reported estimates are compatible with an assumption of no effect of mobile phone use on glioma risk when the various forms of biases present in the Interphone study are accounted for. Four scenarios of sources of error in self-reported mobile phone use were considered, along with selection bias. Input parameters used for simulations were those obtained from Interphone validation studies on reporting accuracy and from using a nonresponse questionnaire.
Results: We found that the scenario simultaneously modeling systematic and random reporting errors produced a J-shaped relationship perfectly compatible with the observed relationship from the main Interphone study with a simulated spurious increased relative risk among heaviest users (odds ratio = 1.91) compared with never regular users. The main determinant for producing this J shape was higher reporting error variance in cases compared with controls, as observed in the validation studies. Selection bias contributed to the reduced risks as well.
Conclusions: Some uncertainty remains, but the evidence from the present simulation study shifts the overall assessment to making it less likely that heavy mobile phone use is causally related to an increased glioma risk.
Competing Interests: Disclosure: M.F. was vice chairman (2012–2020) of the International Commission on Non-Ionizing Radiation Protection, an independent body setting guidelines for nonionizing radiation protection. She has served as advisor to a number of national and international public advisory and research steering groups concerning the potential health effects of exposure to nonionizing radiation, currently for the World Health Organization. M.F. is the principal investigator of the Swedish part of the COSMOS study, which has been funded by the Swedish Research Council, AFA Insurance, the Swedish Research Council for Health, Working Life and Welfare, the Swedish Radiation Safety Authority, and VINNOVA. VINNOVA received funds for this purpose from TeliaSonera AB, Ericsson AB, and Telenor Sverige AB, to cover part of the data collection (ended 2012). The provision of funds to the COSMOS study investigators via VINNOVA was governed by agreements that guarantee COSMOS’ complete scientific independence. The remaining authors declare they have no conflicts of interest.
(Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)