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PHQ-9 Depression Screener (NHANES Random Sample)

Source: R/data.R
phq9_nhanes.Rd

A simple random sample of 1000 respondents to the Patient Health Questionnaire 9-item (PHQ-9) depression screener in the U.S. National Health and Nutrition Examination Survey (NHANES), September 2024 release (file DPQ_L). Respondents were sampled from the 5455 who answered all nine items with a valid response (0 to 3). There is no selection on scores, so the data keep the many zero responses of a general population sample: 21.6% have a sum score of zero (24.3% among all complete responders). Intended for the hurdle partial credit model, see hurdle_acat. For a sample with higher symptom levels, see phq9.

Usage

phq9_nhanes

Format

A data frame with 1000 rows and 10 variables:

q1

Little interest or pleasure in doing things. Integer 0–3.

q2

Feeling down, depressed, or hopeless. Integer 0–3.

q3

Trouble falling/staying asleep, or sleeping too much. Integer 0–3.

q4

Feeling tired or having little energy. Integer 0–3.

q5

Poor appetite or overeating. Integer 0–3.

q6

Feeling bad about yourself, or that you are a failure or have let yourself or your family down. Integer 0–3.

q7

Trouble concentrating on things, such as reading the newspaper or watching television. Integer 0–3.

q8

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. Integer 0–3.

q9

Thoughts that you would be better off dead, or of hurting yourself in some way. Integer 0–3.

seqn

NHANES respondent sequence number (SEQN), for linking to other NHANES files of the same cycle.

Each item uses a four-point ordinal response scale, scored 0 ("Not at all"), 1 ("Several days"), 2 ("More than half the days") and 3 ("Nearly every day"). The highest categories are sparse for some items, for example 1% of respondents chose 3 on q9.

Source

U.S. Centers for Disease Control and Prevention, National Center for Health Statistics. National Health and Nutrition Examination Survey, September 2024 release, file DPQ_L. https://wwwn.cdc.gov/nchs/nhanes/search/datapage.aspx?Component=Questionnaire&CycleBeginYear=2024. NHANES data are released to the public domain by the U.S. federal government (https://www.cdc.gov/nchs/policy/data-release-policy.html).

Details

Codes 7 (refused) and 9 (don't know) were treated as missing, and respondents with any missing item were left out before sampling. The NHANES survey weights and design are ignored, so the data do not give population estimates. The script data-raw/phq9_nhanes.R in the package source rebuilds the dataset from the NHANES file.

References

Kroenke, K., Spitzer, R. L., & Williams, J. B. W. (2001). The PHQ-9: Validity of a brief depression severity measure. Journal of General Internal Medicine, 16(9), 606–613. doi:10.1046/j.1525-1497.2001.016009606.x

Examples

data(phq9_nhanes)
table(rowSums(phq9_nhanes[, 1:9]) == 0)
#> 
#> FALSE  TRUE 
#>   784   216