"Two of today's top-selling brands of whitening toothpaste,ShinyWhite and SparkleDent, are now available in extra-strength form. Dentists promote the use of regular-strength ShinyWhite 50% more than they promote the use of regular-strength SparkleDent, so people who want an effective whitening toothpaste in extra-strength form should choose ShinyWhite."
The argument is flawed in its conclusion to promote extra-strength SparkleDent based on the certification given to regular-strength SparkleDent. The argument is not comparing two things of same quality. Also, the argument retorts to the appeal of authority to substantiate its initial statement that regular-strength SparkleDent is better than regular-strength ShinyWhite.
The pamphlet does not provide the features or concrete test results between the performance of extra-strength ShinyWhite to that of SparkleDent. There is no evidence that these two toothpastes will perform the same way at different quality levels. Also, the recommendation should be personalized to different types of people. Some may not withstand an extra-strength toothpaste. For them, a statutory warning should be given as to what problems may occur due to an extra-strength toothpaste.
The pamphlet refers to the promotion of dentists who recommend the use of regular-strength ShinyWhite to that of SparkleDent. The pamphlet does not give any specifications about those doctors like their medical association affiliation, recognition by the government and the sampling is confined to a particular locality or does it talks about the country as a whole.
A certified doctor's association, which is accepted by both ShinyWhite and SparkleDent, should perform valid and concrete tests under different quantitative and qualitative levels. The tests should be done over adequate number of times to prevent any sampling error. Then the performance of these two tooth-pastes should be compared. With proper test results for regular and extra-strength category, the general public would be sane enough to choose themselves the toothpaste they would like to use.
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