Type of employment, indicator for chronic illness, drug, or alcohol use these variables are likely useful to add to the regression to control for important omitted variables.
What is sleep pattern?
The word sleep pattern, commonly referred to as a sleep-wake pattern, refers to a person's schedule for going to bed and getting up as well as their napping habits. The frequency and length of sleep disruptions may also be part of the sleep pattern.
Type of employment, Chronic illness and drug/alcohol use they ought to be included in regression since they disturb sleep patterns.
As a result, option (a) Type of employment. (b) Indicator for chronic illness. (c) Drug or alcohol use is correct.
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