Mental Health Study Example Alachua County, Florida

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Mental Health Study ExampleAlachua County,
Florida

• Purpose Relate mental impairment to two
  explanatory variables, the severity of life and
  socioeconomic status

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The Dataset

• Subject a randomly assigned id number (1, 2,
  3,)
• Mental impairment ordinal response with
  categories well, mild symptom formation,
  moderate symptom formation, and impaired
• Life events a composite measure of the number
  and severity of important life events such as
  birth of a child, new job, divorce in the family
  that occurred to the subject within the past
  three years (0, 1,,9)
• Socioeconomic status (SES) measured here as
  binary (1 high and 2 low)

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The Main Effects Model
Proportional odds model J 4 response
categories (well, mild, moderate, impaired) x1
life events (0,1,2,,9) x2 SES (1 low, 2
high)
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SAS Code Output

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What does this mean?

• and
• The cumulative probability of starting at the
  well end of the scale decreases (b1) as the life
  events score increases and also increases at the
  higher level of SES (b2).

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• SES Effect
• for x1 4.275, the mean life events score
• THIS WILL BE P(Y lt 2) FORMULA

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• Life Events Effect
• for x2 1, high SES

for x2 0, low SES