We included in a case-control study on brain tumours and mobile and cordless 
telephones 1,617 patients aged 20-80 years of both sexes diagnosed during 
January 1, 1997 to June 30, 2000. They were alive at the study time and had 
histopathology verified brain tumour. One matched control to each case was 
selected from the Swedish Population Register. The study area was the 
Uppsala-Orebro, Stockholm, Linköping and Göteborg medical regions of Sweden. 
Exposure was assessed by a questionnaire that was answered by 1,429 (88%) cases 
and 1,470 (91%) controls. In total use of analogue cellular telephones gave an 
increased risk with odds ratio (OR)=1.3, 95% confidence interval (CI)=1.04-1.6, 
whereas digital and cordless phones did not overall increase the risk 
significantly. Ipsilateral use of analogue phones gave OR=1.7, 95% CI=1.2-2.3, 
digital phones OR=1.3, 95% CI=1.02-1.8 and cordless phones OR=1.2, 95% 
CI=0.9-1.6. The risk for ipsilateral use was significantly increased for 
astrocytoma for all studied phone types, analogue phones OR=1.8,95% CI=1.1-3.2, 
digital phones OR=1.8, 95% CI=1.1-2.8, cordless phones OR=1.8, 95% CI=1.1-2.9. 
Use of a telephone on the opposite side of the brain was not associated with a 
significantly increased risk for brain tumours. Regarding anatomical area of the 
tumour and exposure to microwaves, the risk was increased for tumours located in 
the temporal area on the same side of the brain that was used during phone 
calls, significantly so for analogue cellular telephones OR=2.3, 95% CI=1.2-4.1. 
For acoustic neurinoma OR=4.4, 95% CI=2.1-9.2 was calculated among analogue 
cellular telephone users. When duration of use was analysed as a continuous 
variable in the total material, the risk increased per year for analogue phones 
with OR=1.04, 95% CI=1.01-1.08. For astrocytoma and ipsilateral use the trend 
was for analogue phones OR=1.10, 95% CI=1.02-1.19, digital phones OR=1.11, 95% 
CI=1.01-1.22, and cordless phones OR=1.09, 95% CI=1.01-1.19. There was a 
tendency of a shorter tumour induction period for ipsilateral exposure to 
microwaves than for contralateral, which may indicate a tumour promotor effect.