Retrospective Investigation of Inhalant Use and Depression Scale

Task:

A retrospective investigation of inhalant use was conducted using data collected from the total population of 7th-grade and 8th-grade students attending a public middle school and 9th-grade and 10th-grade students attending a public high school in a city of about 50,000 people. The ages of the 904 students in the population ranged from 11 years to 18 years with 61% of students age 14 or younger. Of the population, 47% were male students and 53% were female students. Slightly more than half (55%) were Caucasian, 39% were African American, and 6% were grouped as “other. The category of “other” included Native Americans, Latin Americans, Mexican Americans and Asian Americans. The item pertaining to inhalant used stated on the questionnaire is the following:

“On how many occasions (if any) have you sniffed glue, or breathed the contents of aerosol spray cans, or inhaled other gases or sprays in order to get high (a) in your lifetime? (b) during the last 12 months? (c) during the past 30 days?”
The following table shows the lifetime, past year, and mast month reported inhalant use, by grade in school.

1a.  How many of the students were classified as “other”?
1b. How many students in all grades combined reported using inhalants during the past month?
1c. Supposed you surveyed 8th graders in a different city and found that 64 out of the 211 students in that city reported using inhalants in their lifetimes. In terms of percentages, which city has a bigger problem with inhalant use by 8th graders? Explain.
1d. At all grade levels, the percentage of students that used inhalants in the past year is lower than the percentage that used them in their lifetimes. Does this make sense? Explain.
1e. The numbers of students who used inhalants in the past month at grades 9 and 10 are the same, yet the percentages are different. Explain why this result is possible.


2. Some researchers developed a new scale measuring reasons people give for being depressed. One of the subscales is “Interpersonal Conflict”. For this subscale, examinees rate each of the following six items on a 4-point scale from 1 (definitely not a reason) to 4 (definitely a reason for being depressed): “Other people don’t like me”, “I can’t make friends”, “Other people isolate me”, “People treat me poorly”, “People don’t give me the respect I deserve”, and “Other people criticize me.” Another of the subscales is “Achievement” on which examinees rate these six items: “I’ve failed to achieve a specific goal I set for myself”, “I am not fulfilling my potential”, “I’m not living up to my personal standard”, “I can’t accomplish what I want to”, “I can’t get done the things I should be able to”, and “I have not become the person I set out to be”.
On the following page is a partially completed table showing the distributions for the two subscales. Shown are subscale scores (X), frequency of their occurrence (f), cumulative frequency of their occurrence (cf) and cumulative percentage of their occurrence (c%), the latter expressed as a whole number between 0 and 100.
Important note - A cumulative percentage can also be interpreted as a percentile rank. For example, if a person has a percentile rank of 44, this is interpreted to mean that s/he scored as high or higher than 44% of all the individuals studied.
Use the table on the following page to answer the following questions:
2a.  Complete the table on the following page.
2b. What is the percentile rank for an examinee with a raw score (X) of 10 on the “Interpersonal Conflict” subscale?
2c.  Do you think that someone who took the subscales would learn more about themselves if you gave them their raw score or if you gave them their percentile rank? Explain.