Statistics for Dummies by Deborah Jean Rumsey Read Free Book Online

the statistics. In fact, you'll often see a real gap between a headline and the "fine print" in such media stories.
    A study conducted a few years back evaluated videotaped sessions of 1,265 patient appointments with 59 primary-care physicians and 6 surgeons in Colorado and Oregon. This study found that physicians who had not been sued for malpractice spent an average of 18 minutes with each patient, compared to 16 minutes for physicians who had been sued for malpractice.
    Wow, is two minutes really that important? When the study was reported by the media with the headline, "Bedside manner fends off malpractice suits", this study seemed to say that if you are a doctor who gets sued, all you have to do is spend more time with your patients, and you're off the hook.
    What's really going on? Am I supposed to believe that a doctor who has been sued needs only add a couple more minutes of time with each patient, and he can avoid being sued? Think about some of the other possibilities that may be involved here. It could be the case that doctors who don't get sued are just better doctors, ask more questions, listen more, and tell their patients more of what to expect, thereby taking more time; if so, what a doctor does during that time counts much more than how much time the doctor actually spends with each patient. But what about this possibility: Maybe the doctors who get sued are doing more difficult types of operations, or maybe they're specialists of some kind. Unfortunately, the article doesn't give you this information. Another possibility is that the doctors who don't get sued have fewer patients and, therefore, are able to spend more time with each patient and keep better track of them. At any rate, the fine print here doesn't quite match the hype, and when you read or hear about stories like these, watch out for similar gaps between what the headline claims and what the study actually found.
    Reporting beyond the scope
    You may wonder how political candidates find out about how their constituents feel. They conduct polls and surveys. Many surveys are done by an independent group, such as The Gallup Organization; others are done by representatives of the candidates themselves, and their methods can differ greatly from candidate to candidate, or from survey to survey.
    In the 1992 presidential election, Ross Perot made quite a splash on the political scene. His group, United We Stand America, gained momentum and, ultimately, Ross Perot and his supporters made an impact on the election results. Often during debates and campaign speeches, Perot would give statistics and make conclusions about how Americans felt about certain issues. But was Mr. Perot always clear on how "Americans" felt, or was he simply clear about how his supporters felt? One of the vehicles Ross Perot used to get a handle on the opinions of Americans was to publish a questionnaire in the March 21, 1992, TV Guide , asking people to fill it out and send it to the address provided. Then he compiled the results of the survey and made them part of his campaign platform. From these results, he concluded that over 80% of the American people agreed with him on these issues. (Note, however, that he received only 18.91% of the vote in 1992.)
    Part of the trouble with Mr. Perot's claims is the way the survey was conducted. In order to respond, you had to purchase the TV Guide , you had to have strong enough feelings about the survey to fill it out, and you had tomail it in yourself with your own stamp. Who is most likely to do this? Those who have strong opinions. In addition, the wording of the questions in this survey probably encouraged the people who agreed with Ross Perot to fill out the survey and send it in; those who didn't agree with him were more likely to ignore the survey.
Tip 
If you can tell, based on the wording of the question, how the researcher wants you to respond to it, you know you're looking at a leading question. (See Chapter 16 for more