The results of a five-year, multimillion dollar study conducted by Interphone on the health effects of cell phone use were lauded by US and European wireless industry officials who say the research validates their position against any conclusive link between mobile phone use and brain tumors. Arguing, however, that the study underestimated the risk of tumors, independent scientists took issue with the Interphone methodology as they called for further research that takes into account heavy users and the effects of cell phone use on the developing brains of children and adolescents. Covering wireless handset users in 13 countries, the Interphone project constitutes the largest control study to date on potential links between brain tumors and cell phone use. Observers also indicate that wireless industry sources financed nearly $6.8 million of the project’s total $23.7 million price tag. The study covered 2,700 persons between the ages of 30 and 59 with glioma, 2,400 persons in the same age group with meningioma, and matched controls. Twenty-one study researchers agreed that “no increase in risk of glioma or meningioma was observed with use of mobile phones.” Although there were suggestions of increased glioma risk at the highest exposure levels, the researchers admitted that “biases and error” prevented a causal interpretation and that the potential effects of long-term, heavy cell phone use thus warranted further investigation. The researchers further acknowledged that the majority of study subjects were not heavy cell phone users as the median lifetime cumulative call time for the study participants “was around 100 hours, with a median of 2 to 2.5 hours of reported use per month.” As wireless association CTIA noted that Interphone’s finding of no overall increased risk of brain cancer “is consistent with conclusions reached in an already large body of scientific research on the subject,” some independent scientists countered that the study’s focus on occasional cell phone users biased the study results against the discovery of harmful effects. Still, one analyst decreed: “while certain findings were inconclusive and some aspects of research methodology questioned, the data largely supports global scientific consensus that a causal association between mobile phone use and brain cancer cannot be identified at this time.”