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Chapter 4: Q. 50 (page 263)

Sealing your teeth- Many children have their molars sealed to help prevent cavities. In an experiment, 120children aged6–8were randomly assigned to a control group, a group in which sealant was applied and reapplied periodically for 36months, and a group in which fluoride varnish was applied and reapplied periodically for 42months. After 9years, the percent of initially healthy molars with cavities was calculated for each group. Identify the experimental units and the treatments.

Short Answer

Expert verified

The experimental units is fluoridation of water , number of dental cavities and diet and the treatments are to randomize it , control it directly and pair-match .

Step by step solution

01

Given information

We need to find that the experimental units and the treatments .

02

Explanation

The experimental units and factors in this would be fluoridation of water , number of dental cavities and diet.

Here in this case according to experimental design we are given that After9years, the percent of initially healthy molars with cavities was calculated for each group.

The treatment would be to randomize it , control it directly and pair-match .

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