First Assignment Coursera - Regression Models in Practice

I have chosen the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC)

http://pubs.niaaa.nih.gov/publications/AA70/AA70.htm

1. Describe the sample

a) Describe the study population (who or what was studied).

NESARC contains an extensive battery of questions about present and past alcohol consumption, AUDs, and the use of alcohol treatment services. NESARC also included similar questions related to tobacco and illicit drug use (including nicotine dependence and drug use disorders) as well as questions designed to determine a wide variety of psychiatric disorders such as major depression, anxiety disorders, and personality disorders. 

 Furthermore, NESARC contained questions that operationalized the criteria set forth in the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM–IV) for the following psychiatric disorders:

• Five mood disorders (major depressive disorder, bipolar I and bipolar II disorders, dysthymia, and hypomania)
• Four anxiety disorders (panic with and without agoraphobia, social phobia, specific phobia, and generalized anxiety)
• Seven personality disorders (avoidant, dependent, obsessive–compulsive, paranoid, schizoid, histrionic, and antisocial disorders).

b) Report the level of analysis studied (individual, group, or aggregate).

Individuals were randomly selected from a systematic sample of group quarters in these PSUs.The Census 2000 Group Quarters Inventory formed the sampling frame for the group quarters portion of the NESARC sample. 

c) Report the number of observations in the data set.

43093 Total, 8209 1. Northeast 8991 2. Midwest 16156 3. South 9737 4. West

d) Describe your data analytic sample (the sample you are using for your analyses).

397-398 S2AQ8A HOW OFTEN DRANK ANY ALCOHOL IN LAST 12 MONTHS

 --------------------------------------------- 

 1865 1. Every day 

 1210 2. Nearly every day 

 2619 3. 3 to 4 times a week 

 2914 4. 2 times a week 

 3261 5. Once a week 

 3557 6. 2 to 3 times a month 

 2663 7. Once a month 1805 8. 7 to 11 times in the last year 

 3210 9. 3 to 6 times in the last year 

 3637 10. 1 or 2 times in the last year 

 205 99. Unknown 

16147 BL. NA, former drinker or lifetime abstainer 

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2. Describe the data collection procedure

a) Report the study design that generated that data (for example: data reporting, surveys, observation, experiment).

Surveys, Data were collected in face-to-face, computer-assisted personal interviews conducted in respondents’ homes. The NESARC response rate was 81 percent.

b) Describe the original purpose of the data collection.

The major purposes of the Wave 1 and Wave 2 NESARC are to:

• Determine the prevalence, incidence, stability, and recurrence of AUDs and their associated disabilities in the general U.S. population.
• Estimate the magnitude of health disparities in AUDs and their associated disabilities among population subgroups defined by gender, race/ethnicity, disability, sexual orientation, age, and socioeconomic status.
• Estimate the size, characteristics, and changing nature of populations of special concern, including alcohol abusers and other people in the general population who are impaired or affected by the use of alcohol (e.g., those engaging in binge drinking or impaired driving).
• Estimate changes in AUDs and their associated disabilities over time, and identify factors associated with the natural history of AUDs.
• Determine the number of people receiving alcohol treatment through various treatment programs and services, including those not otherwise represented in surveys of treatment facilities; measure the unmet need for alcohol treatment services; and identify barriers to seeking treatment.
• Determine the associations between AUDs and their major physical and mental disabilities, differentiating drug-induced disorders from those reflecting true, independent mental conditions.
• Determine the boundaries between safe and hazardous drinking levels and patterns for various types of AUDs and their associated medical, social, and psychological sequelae.

c) Describe how the data were collected.

NESARC participants are variable in lifestyle and ages.

To ensure that minority and special populations were well represented in the sample, NESARC oversampled Blacks, Hispanics, and young adults ages 18–24. As a result, the survey produced enough minority respondents to answer questions of race/ethnic disparities in comorbidity and access to health care services

d) Report when the data were collected.

In 2001—2002, the National Institute on Alcohol Abuse and Alcoholism (NIAAA) conducted the first wave of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC),The second wave of the survey took place from 2004 to 2005. 

e) Report where the data were collected.

They represented all regions of the United States. In addition to sampling people living in traditional households, NESARC investigators questioned military personnel living off base and people living in a variety of group accommodations such as boarding or rooming houses and college quarters. By including these different types of housing, the investigators were able to obtain data on people not typically captured by household surveys.

 3. Measures section describing your variables and how you managed them to address your own research question

a) Describe what your explanatory and response variables measured.

explanatory variable:

397-398 S2AQ8A HOW OFTEN DRANK ANY ALCOHOL IN LAST 12 MONTHS

 --------------------------------------------- 

 1865 1. Every day 

 1210 2. Nearly every day 

 2619 3. 3 to 4 times a week 

 2914 4. 2 times a week 

 3261 5. Once a week 

 3557 6. 2 to 3 times a month 

 2663 7. Once a month 1805 8. 7 to 11 times in the last year 

 3210 9. 3 to 6 times in the last year 

 3637 10. 1 or 2 times in the last year 

 205 99. Unknown 

16147 BL. NA, former drinker or lifetime abstainer 

---------------------------------------------------------------------------------------

b) Describe the response scales for your explanatory and response variables.

c) Describe how you managed your explanatory and response variables.

response variable

 SECTION 9: GENERALIZED ANXIETY (GENERAL ANXIETY) -
 3020-3020 S9Q1A EVER HAD 6+ MONTH PERIOD FELT TENSE/NERVOUS/WORRIED MOST OF TIME
 3128 1. Yes 38225 2. No 1740 9. Unknown

 3021-3021 S9Q1B EVER HAD 6+ MONTH PERIOD FELT VERY TENSE/NERVOUS/WORRIED MOST OF TIME ABOUT EVERYDAY PROBLEMS
 358 1. Yes 37867 2. No 1740 9. Unknown 3128 BL. NA, had 6+ month period feeling tense/nervous/worried most of the time

 3022-3022 S9Q31 IN WORST PERIOD, EVER WORRY A LOT ABOUT THINGS YOU USUALLY DIDN'T WORRY ABOUT
2336 1. Yes 1115 2. No 35 9. Unknown 39607 BL. NA, never or unkn. if ever had 6+ month pd. being tense/nervous/worried

 3023-3023 S9Q32 IN WORST PERIOD, EVER WORRY ABOUT MORE THAN ONE THING
 2644 1. Yes 808 2. No 34 9. Unknown 39607 BL. NA, never or unkn. if ever had 6+ month pd. being tense/nervous/worried

 3024-3024 S9Q33 IN WORST PERIOD, EVER FIND IT DIFFICULT TO STOP BEING TENSE/NERVOUS/WORRIED
 2715 1. Yes 742 2. No 29 9. Unknown 39607 BL. NA, never or unkn. if ever had 6+ month pd. being tense/nervous/worried

 3025-3025 S9Q34 IN WORST PERIOD, EVER WORRY ABOUT THINGS THAT WERE VERY UNLIKELY TO HAPPEN
1418 1. Yes 2019 2. No 49 9. Unknown 39607 BL. NA, never or unkn. if ever had 6+ month pd. being tense/nervous/worried

c) Describe how you managed your explanatory and response variables.

confounders:

I will control for different confounders like:

 Page 302: SECTION 4A: MAJOR DEPRESSION (LOW MOOD I)
Page 316: SECTION 4B: FAMILY HISTORY (III) OF MAJOR DEPRESSION
Page 319: SECTION 4C: DYSTHYMIA (LOW MOOD II)
Page 329: SECTION 5: MANIA OR HYPOMANIA (HIGH MOOD)
Page 341: SECTION 6: PANIC DISORDERS AND AGORAPHOBIA (ANXIETY)
Page 355: SECTION 7: SOCIAL PHOBIA (SOCIAL SITUATIONS)
Page 371: SECTION 8: SPECIFIC PHOBIA (SPECIFIC SITUATIONS)
Page 386: SECTION 9: GENERALIZED ANXIETY (GENERAL ANXIETY)
Page 403: SECTION 10: PERSONALITY DISORDERS (USUAL FEELINGS/ACTIONS)
Page 419: SECTION 11A: ANTISOCIAL PERSONALITY DISORDER (BEHAVIOR)