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L. Lloyd Morgan [bilovsky@aol.com]1 Interphone Studies To Date An Examination of Poor Study Design Resulting in an UNDER-ESTIMATION of the 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
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L. Lloyd Morgan [bilovsky@aol.com]2 Methodology Methodology What If There Is No Risk of Brain Tumors? ORs 1.0 Think coin tossing OR=1.0 are excluded ~5% of ORs would be significant ORs 1.0 Calculate ratio: 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
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L. Lloyd Morgan [bilovsky@aol.com]3 Methodology Methodology Calculate 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)
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L. Lloyd Morgan [bilovsky@aol.com]4 Results Results Percent Significant Findings By Category Expectation: ~5%
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L. Lloyd Morgan [bilovsky@aol.com]5 Results Results Ratio (OR 1.0): Exposures: >10 Year and <10 Year
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L. Lloyd Morgan [bilovsky@aol.com]6 Results Results Ratio by Category
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L. Lloyd Morgan [bilovsky@aol.com]7 Results Results Ratio by Brain Tumor Type
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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
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L. Lloyd Morgan [bilovsky@aol.com]9 Flaw 2 Tumors 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%)
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L. Lloyd Morgan [bilovsky@aol.com]10 Flaw 2 Absorbed Radiation Decreases Rapidly w Depth
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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
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L. Lloyd Morgan [bilovsky@aol.com]12 Flaws 3 and 4 Latency Time and the Definition of “Regular Users”
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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
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L. Lloyd Morgan [bilovsky@aol.com]14 Flaw 5 Young Adults and Children Excluded Israel: Ionizing Radiation Korea: Cellphone Rad.Sweden: Cellphone Rad.
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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
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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
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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
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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., …
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L. Lloyd Morgan [bilovsky@aol.com]19Conflict-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)
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L. Lloyd Morgan [bilovsky@aol.com]20 Potential Brain Tumor Risk 30-year Latency Potential Brain Tumor Risk 30-year Latency Poisson Distribution Calculation
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L. Lloyd Morgan [bilovsky@aol.com]21 Potential Public Health Risk
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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
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L. Lloyd Morgan [bilovsky@aol.com]23 I Pray I’m Wrong!
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L. Lloyd Morgan [bilovsky@aol.com]24 Now What? 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
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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
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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
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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
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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
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L. Lloyd Morgan [bilovsky@aol.com]29 Tumors Outside Radiation Plume Are Unexposed Flaw 2 Tumors Outside Radiation Plume Are Unexposed
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L. Lloyd Morgan [bilovsky@aol.com]30 Children Excluded Ionizing Radiation Example Flaw 5 Children Excluded Ionizing Radiation Example
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L. Lloyd Morgan [bilovsky@aol.com]31 Young Adults Excluded Korean Cellphone Study Flaw 5 Young Adults Excluded Korean Cellphone Study
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L. Lloyd Morgan [bilovsky@aol.com]32 Young Adults Excluded Swedish Cellphone Study Flaw 5 Young Adults Excluded Swedish Cellphone Study
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L. Lloyd Morgan [bilovsky@aol.com]33 Tumors Outside Radiation Plume Are Unexposed Flaw 2 Tumors Outside Radiation Plume Are Unexposed
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