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10-Year Cell Phone / Cancer Study Is Inconclusive
crimeandpunishment writes "A major international (retrospective) study into cell phones and cancer, which took 10 years and surveyed almost 13,000 people, is finally complete — and it's inconclusive. The lead researcher said, 'There are indications of a possible increase. We're not sure that it is correct. It could be due to bias, but the indications are sufficiently strong ... to be concerned.' The study, conducted by the World Health Organization and partially funded by the cellphone industry, looked at the possible link between cell phone use and two types of brain cancer. It will be published this week."
At least from this we know that cell phone radiation isn't causing some massive epidemic of brain cancer, and the affects, if there are any, are relatively small. That's not the biggest comfort you could have, but it's something (considering most of us are not going to give up our cell phones anyway).
Qxe4
Yeah, because surveying all those people would be ABSOLUTELY FREE and take NO TIME. Also, it's totally necessary to check everyone. Sampling and statistics don't exist.
How silly.
Not really. Sampling can give accurate results even when sampling a small percentage of the total population. If U.S. political polls select a sample size of between a few hundred and a thousand out of 300 million with only 3% error, it sounds reasonable that 13,000 would be a good sample size of a population 20 times that, giving the same margin of error.
Also remember that, assuming the sample is chosen well (it is a good cross-section of the population and not confined to one specific subgroup), the benefits of adding additional samples drops off. It is essentially logarithmic: at first, adding samples is a huge benefit: after a certain point, the incremental gain from one additional sample is only a tiny fraction of the first samples.
24 beers in a case, 24 hours in a day. Coincidence? I think not!
Cell phones cause so much cancer that ... the most widespread studies cant tell whether they cause cancer at all. That is good news for cell phone users.
So people who are convinced cellphones cause cancer are going to take their "possible increase" and declare scientists just definitively said cellphones cause cancer.
On the other hand, cellphone companies may try to take "we're not sure that it is correct" and declare no link to cancer.
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And even if there is some correlation, people need to put it in perspective.
The last time I talked to a flat-earth-er about their fear of cell phones causing cancer, they had a drink in one hand and a cigarette in the other.
Now that, Alanis Morrissette, is irony.
--- "We've always been at war with Eastasia."
I have a problem with "medical surveys" in that they a prone to make correlation-causation errors. This seems to be a measurable problem that can be tested in the lab. Why don't people do this instead. Put a lab monkey next to an active mobile phone and keep them there for several years. After that, dissect the monkey for any signs of cancer. If there is, then alert the public. You then look into how it happened, i.e the biochemical interactions that caused it. Just "surveying" people introduces biases, other factors like diet and lifestyle and also crackpots.
Have they done this study against other types of radio frequencies like cordless land-line phones? What about emergency services workers that carry radios on their hips until needed...are they being checked for hip-cancer? Doesn't Nike or some other shoe maker have a device that fits inside a shoe so people can listen to FM whilst jogging? Watch out for heel-cancer! The point being, why are cell-phones being singled out as possible culprits where then are so many other devices out there that use radio technology?
I think the media has way too much control over what is allowed to scare us into taking action. It seems that our efforts could be better directed toward something that actually makes sense. Let Mythbusters handle this type of shit.
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The article in USA Today has a nice little gem in it: "The authors acknowledged possible inaccuracies in the survey from the fact that participants were asked to remember how much and on which ear they used their mobiles over the past decade. Results for some groups showed cellphone use actually appeared to lessen the risk of developing cancers, something the researchers described as "implausible."" Now, I don't know why, but something about this statement seems kind of important.
The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
Certainly actual elections tend to fall well outside the +/- 3% accuracy claimed by many of the election-day pollsters.
Because for many of those pollsters accuracy isn't main goal; swaying people, untill the last minute, to vote for the "winners" is.
One that hath name thou can not otter
The uncertainty in the study is due to the low precision of their data- they asked people to try and remember how much they were typically using their cellphones. Surveying more people isn't going to get people to provide more precise data.
Also, unless the needed data is already available somewhere, gathering more data costs more money. As someone else mentioned in a sibling post, there are diminishing returns when increasing your sample size. Eventually the cost of the data will exceed the benefit to the certainty of your results.
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I'm not so sure those percentages are accurate. You'll often see different polls differ by much more than that (far more often than 5% of the time or whatever the confidence level is).
Election polling is just especially difficult, since what counts is if you actually vote and who you vote for, neither of which have been determined at the time of the poll and could change. Election polling isn't simply an opinion poll, but is obviously supposed to reflect the population of people who will actually vote on election day. The polls have differing models of selecting "likely voters", and will thus have numbers that differ more than the margin of error for any single poll. In other words, taking the margin of error for a single poll and comparing it among multiple polls is invalid, since the differing polls used different means of sample selection.
Certainly actual elections tend to fall well outside the +/- 3% accuracy claimed by many of the election-day pollsters.
I guess I haven't found that to be true if you mean "tend to" is more than 50% of the time. Sure, you're going to find some that are outside of the 3% error bars, but you'd also expect that to happen, statistically speaking.
AccountKiller
Science isn't inconclusive. There is statistically significant, or not. In this case, not.
Test another hypothesis or test again if data looks fishy.
To get statistical significance, you don't need to sample the entire population. Beyond a certain number for a certain confidence level, you don't get very much more.
Exactly right.
There was no statistical significance, which means that the cancers (or absence there of) were distributed over cell phone users and non-users (controls) with no preference for either group.
Normally this would be the end of it.
But by the way the reporter worded it (Inconclusive) and (to a lesser extent) the way the Researcher phrased it, indicates a clear predilection toward finding a positive correlation, which they could not do.
The takeaway is not that the study "inconclusive". The scientific takeaway is that there is yet again no evidence of correlation between cancer and cell usage.
Its over. The absence of evidence destroys this theory. Time to move on.
Sig Battery depleted. Reverting to safe mode.
Here are some additional details for those of you so inclined.
Consider a simple binary choice question. This is easily modelled by the binomial distribution which has well understood distributions. (Other distrbutions may be relevant but the principles remain pretty constant across them all.) The standard deviation is given by sqrt[np(1-p)] where n is the sample size and p is the probability of the observation you are interested in (the mean is np so in what follows I will be dividing by n to talk about percentages if you are taking notes). For example, are you male? If the true p is, say, 75% then you need a sample size of approximately 833 to get a 95% confidence interval (2 s.d.) of +/- 3%.
You might also note that the closer the true p is to 50%, the larger the sample size needed. If the true p is 50% you need a sample size of approximately 1100 for the same confidence interval. Furthermore, if you want to get it within 1%, the sample size goes up dramatically - to 10,000.
The population size is pretty much irrelevant. The population matters for ensuring that your sampling is truly random, but political pollsters can use the same sample sizes in Australia (pop ~20 million) as in the US (pop ~300 million) for similar accuracy. (Sampling bias is the reason that political polls can be out by so much - if you call households during work hours you are going to get a very different sample of people than if you call at dinner time.)
The fact that most people don't understand statistics doesn't mean stats are bullshit. It just means people are dumb.