A 12-month study was conducted to determine the relationship between oral hygiene effectiveness and implant maintenance. Subjects in the experimental group received oral hygiene instructions while those in the control group did not. At the conclusion of the study, it was discovered that subjects in both the control and experimental groups had reduced their plaque index scores. The most viable explanation for these results would be:

Assuming that the overall results of a study form a bell-shaped curve, the more dispersed (or spread out) a set of scores is:

Your class is asked to do an exam in theoretical physics. Given that MOST students in class do not know anything about this subject, the distribution of scores would most likely be:

On an alumni survey, respondents were asked to identify the highest degree they had attained: associate degree, bachelor’s degree, master’s degree, or doctorate degree. This variable (college degree completed) is which scale of measurement? (to answer this question, assume that a higher level of education brings a greater capacity of knowledge)

If the test-retest reliability of a measure is low (i.e. low correlation), then it follows that:

Use the terminology choices to best describe the statements. Answers can be used more than once or not at all.

Longitudinal study is a study that takes place over time either looking back or looking forward in time.

Which of the following research design methods attempts to construct the meaning of the human experience?

In a study on the effects of an oral mouth rinse on gingivitis, some patients start using a new gingivitis toothpaste too.

Reading and language development skills were compared between a group of children with a history of dental pain and a group of children without a history of dental pain.