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Methodology What If There Is No Risk of Brain Tumors?

Interphone Studies To Date An Examination of Poor Study Design Resulting in an UNDER-ESTIMATION of the Risk of Brain Tumors L. Lloyd Morgan BEMS, San Diego, 12 June 2008. Methodology What If There Is No Risk of Brain Tumors?. ORs <1.0 would be ~equal ORs>1.0 Think coin tossing

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Methodology What If There Is No Risk of Brain Tumors?

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  1. Interphone Studies To DateAn Examination of Poor Study DesignResulting in an UNDER-ESTIMATIONof the Risk of Brain TumorsL. Lloyd MorganBEMS, San Diego, 12 June 2008 L. Lloyd Morgan [bilovsky@aol.com]

  2. MethodologyWhat If There Is No Risk of Brain Tumors? • ORs <1.0 would be ~equal ORs>1.0 • Think coin tossing • OR=1.0 are excluded • ~5% of ORs would be significant • ORs <1.0 would be ~equal ORs>1.0 • Calculate ratio: OR<1.0/OR>1.0 • 13 Interphone brain tumor studies to date • Exclude 2 overlapping studies and recent (Schlehofer) study • Analysis restricted to 10 Interphone brain tumor studies • Calculate binomial p-values L. Lloyd Morgan [bilovsky@aol.com]

  3. MethodologyCalculate Ratio by Categories by Studies • How to have statistically independent categories? • Compare between studies, not within studies • Categories • Brain Tumors • All • Acoustic Neuroma • Glioma • Meningioma • Years of use (Years) • Cumulative hours of use (Hours) • Cumulative number of calls (Call #) • “Regular” cellphone use (“Regular”) • Years of ipsilateral cellphone use (Years Ipsi) • Years of contralateral cellphone use (Yrs Contra) • Minutes of cellphone use per day (Min/Day) L. Lloyd Morgan [bilovsky@aol.com]

  4. ResultsPercent Significant Findings By CategoryExpectation: ~5% L. Lloyd Morgan [bilovsky@aol.com]

  5. ResultsRatio (OR<1.0/OR>1.0): Exposures: >10 Year and <10 Year L. Lloyd Morgan [bilovsky@aol.com]

  6. ResultsRatio by Category L. Lloyd Morgan [bilovsky@aol.com]

  7. ResultsRatio by Brain Tumor Type L. Lloyd Morgan [bilovsky@aol.com]

  8. Interphone Protocol Design Flaws • Flaw 1: Selection Bias • Participating controls use cellphones more than non-participating controls • Weighted average control participation rate: 59% • Löon 2004: 20% control refused; 34% used, 59% did not use • Underestimates risk • Flaw 2: Tumors outside the radiation plume are unexposed • Unexposed tumors treated as exposed • Plume volume small relative to brain volume • Well know since 1994 (4 previous papers) • Underestimates risk L. Lloyd Morgan [bilovsky@aol.com]

  9. Flaw 2Tumors Outside Radiation Plume Are Unexposed • Radiation plume’s volume is small % of brain’s volume • Ipsilateral: exposed Contralateral: unexposed • Absorbed radiation decreases rapidly with plume penetration depth • Half-way to the brain’s mid-line, >90% of energy is absorbed • Percentage of absorbed cellphone radiation • Ipsilateral temporal lobe: 50-60% (wt. av.=53%) • ~15% of brain’s volume • “Ipsilateral” cerebellum: 12-25% (wt. av.=19%) • ~5% of brain’s volume • 62-85% of absorbed radiation is in ~20% of the brain’s volume • Plume decreases rapid with depth (actual exposed brain’s volume: <20%, perhaps 15%) L. Lloyd Morgan [bilovsky@aol.com]

  10. Flaw 2Absorbed Radiation Decreases Rapidly w Depth L. Lloyd Morgan [bilovsky@aol.com]

  11. Interphone Protocol Design Flaws • Flaw 3: Latency time • Known latency times • Ionizing radiation & brain tumor: 20-40 years • Smoking & lung cancer: ~30 years • Asbestos & mesothelioma: 20-40+ years • Short latency times underestimates risk • Flaw 4: Definition of “regular” user • “Regular” user: At least once a week for 6 months or more • If definition of “regular” smoker were used, would a risk of lung cancer be found? • Definition of “regular” user underestimates risk L. Lloyd Morgan [bilovsky@aol.com]

  12. Flaws 3 and 4Latency Time and the Definition of “Regular Users” L. Lloyd Morgan [bilovsky@aol.com]

  13. Interphone Protocol Design Flaws • Flaw 5: Young adults and children excluded • Children and young adults at greater risk than adults • Interphone Protocol: 30-59 years • Some studies reduce minimum age to 20 years • Underestimates risk L. Lloyd Morgan [bilovsky@aol.com]

  14. Flaw 5Young AdultsandChildrenExcluded Sweden: Cellphone Rad. Korea: Cellphone Rad. Israel: Ionizing Radiation L. Lloyd Morgan [bilovsky@aol.com]

  15. Interphone Protocol Design Flaws • Flaw 6: Comparison cellphone radiated power: higher vs lower • Analog Vs Digital phones • No longer possible • Rural Vs Urban users • Underestimates risk L. Lloyd Morgan [bilovsky@aol.com]

  16. Interphone Protocol Design Flaws • Flaw 7: Cordless phone, walkie-talkie, Ham, and proximity to TV & radio transmitters • Treated as unexposed • Underestimation of risk • Flaw 8: Exclusion of brain tumor types • Includes only acoustic neuroma, glioma & meningioma • Other brain tumor types are excluded • For example lymphoma and neuroepithelial brain tumors • Underestimates risk • Flaw 9: Exclusion of brain tumor cases because of death • Underestimates risk of most deadly brain tumors L. Lloyd Morgan [bilovsky@aol.com]

  17. Interphone Protocol Design Flaws • Flaw 10: Recall bias • Light users underestimate use • Heavy users overestimate use • Result: Large underestimation of risk L. Lloyd Morgan [bilovsky@aol.com]

  18. How to Resolve Flaws • Increase diagnosis eligibility time • Nine Interphone studies: weighted-average 2.6 years • Hardell et al. eligibility time: 6 years • Lower age range to <15 years • Pay controls (and cases?) for participation in study • Do not tell controls what is the purpose of the study • Interview proxies in case of death • Separately report both case and proxy interview results • Treat unexposed tumors as unexposed • Etc., Etc., Etc., … L. Lloyd Morgan [bilovsky@aol.com]

  19. Conflict-of-Interest • Cellphone Industry • Interphone funding is inadequate to resolve flaws • More funding, greater potential of substantial revenue loss • Researchers’ conflict-of-interest (unconscious?) • Source of funds is known in spite of “Firewall” • Honest, but • “Don’t bite the hand that feeds you” • 90 significant protective results • Ignored by authors (no commentary in the text) L. Lloyd Morgan [bilovsky@aol.com]

  20. Potential Brain Tumor Risk30-year LatencyPoisson Distribution Calculation L. Lloyd Morgan [bilovsky@aol.com]

  21. Potential Public Health Risk L. Lloyd Morgan [bilovsky@aol.com]

  22. Conclusions • Interphone results substantially underestimate the risk of brain tumors • Great majority of results have OR<1.0 • Either cellphone use is protective, or the study has major flaws • Ratio is lowest for highest exposures: ipsilateral use or>10 years of use • Significant risk found for >10 years and ipsilateral use • Without design flaws Odds Ratios would increase substantially • Cellphone industry’s conflict-of-interest is obvious • Government: ignores potential epidemic (see no evil) • Public health impact is enormous • Industry independent studies are required L. Lloyd Morgan [bilovsky@aol.com]

  23. I Pray I’m Wrong! L. Lloyd Morgan [bilovsky@aol.com]

  24. Now What?Based on CBTRUS Incidence Data • Window closed for case-control studies • No unexposed cases remain • Cohort studies • Unable to know users of company owed cellphones • Unable to interview cellphone users • Requires enormous numbers • 1,000,000 user-years will find (assuming cellphones do not increase risk) • ~6 acoustic neuromas • ~54 gliomas • ~45 meningiomas • Requires ~1 billion user-years to analyze by • Gender, SES, Years of use ,Exposed tumors only • Requires 30 year cohort study L. Lloyd Morgan [bilovsky@aol.com]

  25. Interphone Protocol Design Flaws • Flaw 11: Recall bias • Interview cases immediately after diagnosis and 6 months after surgery • Improved memory and cognition 6 months after surgery • Flaw 12: Observational bias • Interviewer not blinded with face-to-face interviews • Mailed questionnaires provide blindness • Supplement by phone as necessary • Flaw 13: Too few cases for statistical power • Nine Interphone Brain Tumor Studies: Use for >10 years • Average 18 cases per study • At minimum requires 2-fold more cases and controls for sufficient statistical power L. Lloyd Morgan [bilovsky@aol.com]

  26. Design Changes to Resolve Flaws • Treat unexposed tumors as unexposed • Tumors outside radiation plume • Data was available, but to date not used, or even discussed • Too few cases? • Treat RF/MW exposures and exposed • Cordless phone, walkie-talkie radios, Ham transmitters • Overweight rural users or increase eligibility time • Compare risk of brain tumor with rural and urban users • Requires sufficient number of cases and controls • Use questionnaires not face-to-face interviews L. Lloyd Morgan [bilovsky@aol.com]

  27. Design Changes to Resolve Flaws • Reporting “regular” use • Do not publish “regular” use data • At minimum report “regular” use for >5 years, or >10 years • Assumes >3-fold increase in case eligibility range • Latency time: initiation or promotion? • Some researchers assume cellphone can only be promoters • What is evidence for initiation vs promotion? • Follow cases & controls for a longer period L. Lloyd Morgan [bilovsky@aol.com]

  28. Design Changes to Resolve Flaws • Increase eligibility time to 9 years (for sufficient statistical power) • >3-fold increase in cases and controls • Publish results every 3 years • Provides longer latency time • Resolves whether cellphones use initiates or promotes tumors L. Lloyd Morgan [bilovsky@aol.com]

  29. Flaw 2Tumors Outside Radiation Plume Are Unexposed L. Lloyd Morgan [bilovsky@aol.com]

  30. Flaw 5Children ExcludedIonizing Radiation Example L. Lloyd Morgan [bilovsky@aol.com]

  31. Flaw 5Young Adults ExcludedKorean Cellphone Study L. Lloyd Morgan [bilovsky@aol.com]

  32. Flaw 5Young Adults ExcludedSwedish Cellphone Study L. Lloyd Morgan [bilovsky@aol.com]

  33. Flaw 2Tumors Outside Radiation Plume Are Unexposed L. Lloyd Morgan [bilovsky@aol.com]

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