Table of Contents

Component Description

 Depression was measured using the Patient Health Questionnaire (PHQ-9), a nine-item screening instrument that asks questions about the frequency of symptoms of depression over the past 2 weeks. A final follow-up question assesses the overall impairment of the depressive symptoms. Response categories "not at all," "several days," "more than half the days" and "nearly every day" were given a score ranging from 0 to 3. A total score was calculated ranging from 0 to 27. A score of 10 or higher has been well validated and is commonly used in clinical studies to define depression. Other methods for defining depression based on this instrument are also used.

Eligible Sample

Mobile examination center participants 12 years and older were eligible. Due to risk of disclosure, data for 12-17 year olds was not included in the publicly released data file (DPQ). This limited access data file contains only the youth data.

Interview Setting and Mode of Administration

The Depression screener was asked at the mobile examination center, by trained interviewers, using the Computer-Assisted Personal Interviewing (CAPI) system as part of the Mobile Examination Center (MEC) interview in Spanish or English. No proxy or interpreters were permitted for these questions.

Quality Assurance & Quality Control

The CAPI system is programmed with built-in consistency checks to reduce data entry errors. CAPI also uses online help screens to assist interviewers in defining key terms used in the questionnaire.

Approximately 5% of the interviews were recorded and reviewed for quality control purposes.

Data Processing and Editing

Edits were made to ensure the completeness, consistency and analytic usefulness of the data.

Analytic Notes

Depression and depression severity have been defined using various methods in the scientific literature. Researchers may want to pay special attention to records with item non-response (questions that have missing, “don’t know” or “refusal” responses) in deriving a score or severity measure.

MEC exam sample weights should be used for the analyses.

Please refer to the NHANES Analytic Guidelines and the on-line NHANES Tutorial for further details on the use of sample weights and other analytic issues. 
 

References

Codebook and Frequencies

SEQN - Respondent sequence number

Variable Name:
SEQN
SAS Label:
Respondent sequence number
English Text:
Respondent sequence number.
Target:
Both males and females 12 YEARS - 17 YEARS

DPQ001 - CHECK ITEM

Variable Name:
DPQ001
English Instructions:
BOX 1. CHECK ITEM DPQ001: IF INTERVIEW DONE ONLY WITH SURVEY PARTICIPANT (CODED '1' IN RIQ005), CONTINUE. OTHERWISE, GO TO NEXT SECTION.
Target:
Both males and females 12 YEARS - 17 YEARS

DPQ010 - Little interest in doing things

Variable Name:
DPQ010
SAS Label:
Little interest in doing things
English Text:
Over the last 2 weeks, how often have you been bothered by the following problems: little interest or pleasure in doing things? Would you say...
English Instructions:
HANDCARD DPQ1
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 1183 1183
1 Several days 255 1438
2 More than half the days 51 1489
3 Nearly every day 25 1514
7 Refused 0 1514
9 Don't know 0 1514
. Missing 132 1646

DPQ020 - Feeling down, depressed, or hopeless

Variable Name:
DPQ020
SAS Label:
Feeling down, depressed, or hopeless
English Text:
[Over the last 2 weeks, how often have you been bothered by the following problems:] feeling down, depressed, or hopeless?
English Instructions:
HANDCARD DPQ1
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 1185 1185
1 Several days 269 1454
2 More than half the days 39 1493
3 Nearly every day 21 1514
7 Refused 0 1514
9 Don't know 0 1514
. Missing 132 1646

DPQ030 - Trouble sleeping or sleeping too much

Variable Name:
DPQ030
SAS Label:
Trouble sleeping or sleeping too much
English Text:
[Over the last 2 weeks, how often have you been bothered by the following problems:] trouble falling or staying asleep, or sleeping too much?
English Instructions:
HANDCARD DPQ1
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 1015 1015
1 Several days 381 1396
2 More than half the days 66 1462
3 Nearly every day 52 1514
7 Refused 0 1514
9 Don't know 0 1514
. Missing 132 1646

DPQ040 - Feeling tired or having little energy

Variable Name:
DPQ040
SAS Label:
Feeling tired or having little energy
English Text:
[Over the last 2 weeks, how often have you been bothered by the following problems:] feeling tired or having little energy?
English Instructions:
HANDCARD DPQ1
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 833 833
1 Several days 546 1379
2 More than half the days 86 1465
3 Nearly every day 49 1514
7 Refused 0 1514
9 Don't know 0 1514
. Missing 132 1646

DPQ050 - Poor appetite or overeating

Variable Name:
DPQ050
SAS Label:
Poor appetite or overeating
English Text:
[Over the last 2 weeks, how often have you been bothered by the following problems:] poor appetite or overeating?
English Instructions:
HANDCARD DPQ1
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 1247 1247
1 Several days 213 1460
2 More than half the days 33 1493
3 Nearly every day 21 1514
7 Refused 0 1514
9 Don't know 0 1514
. Missing 132 1646

DPQ060 - Feeling bad about yourself

Variable Name:
DPQ060
SAS Label:
Feeling bad about yourself
English Text:
[Over the last 2 weeks, how often have you been bothered by the following problems:] feeling bad about yourself - or that you are a failure or have let yourself or your family down?
English Instructions:
HANDCARD DPQ1
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 1291 1291
1 Several days 172 1463
2 More than half the days 32 1495
3 Nearly every day 19 1514
7 Refused 0 1514
9 Don't know 0 1514
. Missing 132 1646

DPQ070 - Trouble concentrating on things

Variable Name:
DPQ070
SAS Label:
Trouble concentrating on things
English Text:
[Over the last 2 weeks, how often have you been bothered by the following problems:] trouble concentrating on things, such as reading the newspaper or watching TV?
English Instructions:
HANDCARD DPQ1
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 1179 1179
1 Several days 271 1450
2 More than half the days 35 1485
3 Nearly every day 29 1514
7 Refused 0 1514
9 Don't know 0 1514
. Missing 132 1646

DPQ080 - Moving or speaking slowly or too fast

Variable Name:
DPQ080
SAS Label:
Moving or speaking slowly or too fast
English Text:
[Over the last 2 weeks, how often have you been bothered by the following problems:] moving or speaking so slowly that other people could have noticed? Or the opposite - being so fidgety or restless that you have been moving around a lot more than usual?
English Instructions:
HANDCARD DPQ1
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 1359 1359
1 Several days 122 1481
2 More than half the days 18 1499
3 Nearly every day 14 1513
7 Refused 0 1513
9 Don't know 1 1514
. Missing 132 1646

DPQ090 - Thought you would be better off dead

Variable Name:
DPQ090
SAS Label:
Thought you would be better off dead
English Text:
Over the last 2 weeks, how often have you been bothered by the following problems: Thoughts that you would be better off dead or of hurting yourself in some way?
English Instructions:
INTERVIEWER INSTRUCTION: IF DPQ.090 CODED 1, 2, OR 3 PLEASE COMPLETE MENTAL HEALTH OBSERVATION FOR PHYSICIAN REVIEW AT CONCLUSION OF INTERVIEW.
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all 1424 1424
1 Several days 72 1496
2 More than half the days 12 1508
3 Nearly every day 6 1514
7 Refused 0 1514
9 Don't know 0 1514
. Missing 132 1646

DPQ095 - CHECK ITEM

Variable Name:
DPQ095
English Instructions:
BOX 2. CHECK ITEM DPQ095: IF RESPONSE TO ANY OF QUESTIONS DPQ010 - DPQ090 = 1, 2, OR 3, GO TO DPQ100. OTHERWISE, GO TO NEXT SECTION.
Target:
Both males and females 12 YEARS - 17 YEARS

DPQ100 - Difficulty these problems have caused

Variable Name:
DPQ100
SAS Label:
Difficulty these problems have caused
English Text:
How difficult have these problems made it for you to do your work, take care of things at home, or get along with people?
Target:
Both males and females 12 YEARS - 17 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0 Not at all difficult 797 797
1 Somewhat difficult 224 1021
2 Very difficult 20 1041
3 Extremely difficult 5 1046
7 Refused 0 1046
9 Don't know 0 1046
. Missing 600 1646