Investigation of bias related to differences between case and control interview dates in five INTERPHONE countries.
Associations between cellular telephone use and glioma risk have been examined in several epidemiological studies including the 13-country INTERPHONE study. Although results showed no positive association between cellular telephone use and glioma risk overall, no increased risk for long-term users, and no exposure-response relationship, there was an elevated risk for those in the highest decile of cumulative call time. However, results may be biased as data were collected during a period of rapidly increasing cellular telephone use, and as controls were usually interviewed later in time than cases.



Further analyses were conducted in a subset of five INTERPHONE study countries (Australia, Canada, France, Israel, New Zealand) using a post hoc matching strategy to optimize proximity of case-to-control interview dates and age.



Although results were generally similar to the original INTERPHONE study, there was some attenuation of the reduced odds ratios and stronger positive associations among long-term users and those in the highest categories for cumulative call time and number of calls (eighth-ninth and 10th decile).



Proximity and symmetry in timing of case-to-control interviews should be optimized when exposure patterns are changing rapidly with time.
Barcelona Institute for Global Health (ISGlobal), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain; McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, Canada. Electronic address: michelle.turner@isglobal.org.
Michelle C
MC
Turner
The Cancer & Radiation Epidemiology Unit, The Gertner Institute, Chaim Sheba Medical Center, Israel; Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
Siegal
S
Sadetzki
Barcelona Institute for Global Health (ISGlobal), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
Chelsea E
CE
Langer
Barcelona Institute for Global Health (ISGlobal), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
Rodrigo
R
Villegas PhD
Barcelona Institute for Global Health (ISGlobal), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
Jordi
J
Figuerola
Sydney School of Public Health, The University of Sydney, Sydney, Australia.
Bruce K
BK
Armstrong
The Cancer & Radiation Epidemiology Unit, The Gertner Institute, Chaim Sheba Medical Center, Israel.
Angela
A
Chetrit
Cancer Epidemiology Centre, Cancer Council Victoria, Melbourne, Australia.
Graham G
GG
Giles
McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, Canada; Department of Epidemiology and Community Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Canada.
Daniel
D
Krewski
Unité Mixte de Recherche Epidémiologique Transport Travail Environnement Université Lyon 1/IFSTTAR, Université de Lyon, Lyon, France.
Martine
M
Hours
Cancer Control Research, British Columbia Cancer Agency, Vancouver, Canada.
Mary L
ML
McBride
INRS-Institut Armand-Frappier, Université du Québec, Laval, Canada.
Marie-Elise
ME
Parent
University of Montreal Hospital Research Centre, Montreal, Canada.
Lesley
L
Richardson
University of Montreal Hospital Research Centre, Montreal, Canada.
Jack
J
Siemiatycki
School of Population Health, University of Auckland, Auckland, New Zealand.
Alistair
A
Woodward
Barcelona Institute for Global Health (ISGlobal), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
Elisabeth
E
Cardis
D000328:Adult; D001315:Australia; D015982:Bias; D002170:Canada; D016022:Case-Control Studies; D040421:Cell Phone / Q000706:statistics & numerical data*; D004781:Environmental Exposure / Q000009:adverse effects* / Q000706:statistics & numerical data; D015340:Epidemiologic Research Design; D005260:Female; D005602:France; D005910:Glioma / Q000209:etiology*; D006801:Humans; D007407:Interviews as Topic; D007557:Israel; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D009520:New Zealand; D016017:Odds Ratio; D012307:Risk Factors; D013997:Time Factors
Case-control study; Cellular telephone; Glioma; Matching