The Composite International Diagnostic Interview – Short Form (CIDI-SF)
(Generalized Anxiety Disorder)
Description: Diagnostic screening assessment to identify whether the respondent meets criteria for probable Generalized Anxiety Disorder (GAD).
Number of Items: 24
| Item | Question Wording | TILDA Variable |
|---|---|---|
| 1 | During the past 12 months, did you ever have a period lasting one month or longer when most of the time you felt worried, tense, or anxious? | mh301 |
| 2 | People differ a lot in how they worry about things. Did you have a time in the past 12 months when you worried a lot more than most people would in your situation? | mh302 |
| 3 | Has that period ended or is it still going on? | mh303 |
| 4 | How many months or years did it go on before it ended? | mh304 |
| 5 | How many months or years has it been going on? MONTHS | mh305M |
| 6 | How many months or years has it been going on? YEARS | mh305Y |
| 7 | During that period, was/is your worry stronger than in other people? | mh306 |
| 8 | Did/do you worry most days? | mh307 |
| 9 | Did/Do you usually worry about one particular thing, such as your job security or the failing health of a loved one, or more than one thing? | mh308 |
| 10 | Did/Do you find it difficult to stop worrying? | mh309 |
| 11 | Did/Do you ever have different worries on your mind at the same time? | mh310 |
| 12 | How often was/is your worry so strong that you couldn’t/can’t put it out of your mind no matter how hard you tried/try – often, sometimes, rarely or never? | mh311 |
| 13 | How often did/do you find it difficult to control your worry – often, sometimes, rarely, or never? | mh312 |
| 14 | When you were/are worried or anxious, were/are you also restless? | mh314 |
| 15 | When you were/are worried or anxious, were/are you also keyed up or on edge? | mh315 |
| 16 | When you were/are worried or anxious, were/are you also easily tired? | mh316 |
| 17 | When you were/are worried or anxious, did/do you have difficulty keeping your mind on what you were/are doing? | mh317 |
| 18 | When you were/are worried or anxious, were/are you also more irritable than usual? | mh318 |
| 19 | When you were/are worried or anxious, did/do you have tense, sore or aching muscles? | mh319 |
| 20 | When you were/are worried or anxious, did/do you have trouble falling asleep or staying asleep? | mh320 |
| 21 | Did you tell a doctor about your worry or about the problems it was causing? | mh321 |
| 22 | Did you tell any other professional (such as psychologist, social worker, counsellor, nurse, clergy, or other helping professional)? | mh322 |
| 23 | Did you take medication or use drugs or alcohol more than once for the worry or the problems it was causing? | mh323 |
| 24 | How much did/does the worry or anxiety interfere with your life or activities? | mh324 |
Scoring Method:
Response options differ dependent on item.
• Respondents are classified as having Generalized Anxiety Disorder (GAD) during the previous 12 months if they meet all of the following criteria.
Criterion 1: Persistent worry
Respondents must report:
A period of excessive worry, tension, or anxiety.
Symptoms lasting at least six months.
Criterion 2: Severe worry
Respondents must report:
Worry stronger than that experienced by most other people.
Worry occurring on most days.
Worry involving multiple concerns or simultaneous worries.
Criterion 3: Difficulty controlling worry
Respondents must report at least one of the following:
Difficulty stopping the worry.
Worry that cannot be put out of mind.
Difficulty controlling the worry.
Criterion 4: Associated anxiety symptoms
Respondents must report three or more of the following symptoms:
Restlessness.
Feeling keyed up or on edge.
Fatigue.
Difficulty concentrating.
Irritability.
Muscle tension.
Sleep disturbance.
The final variable is coded:
0 = No generalised anxiety disorder
1 = Meets criteria for generalised anxiety disorder in the last 12 months
Citation:
- Kessler, R.C., Andrews, G., Mroczek, D., Üstün, T.B., & Wittchen, H-U. (1998). The World Health Organization Composite International Diagnostic Interview Short Form (CIDI-SF). International Journal of Methods in Psychiatric Research, 7, 171-185.
Example TILDA Papers:
- McDowell, C.P., Dishman, R.K., Vancampfort, D., Hallgren, M., Stubbs, B., MacDonncha, C. and Herring, M.P. (2018). Physical activity and generalized anxiety disorder: results from The Irish Longitudinal Study on Ageing (TILDA). International Journal of Epidemiology, 47(5): 1443–1453. https://doi.org/10.1093/ije/dyy141
Code
gen gad_1 = (mh301==1|mh302==1) & (mh304m>=6|mh304y>=1|mh305m>=6|mh305y>=1|mh304==3|mh305==3)
label variable gad_1 "period of worry lasting at least 6 months"
gen gad_a = mh306==1 & mh307==1 & (mh308==5|mh310==1)
label variable gad_a "severe worry"
gen gad_b = mh309==1 | mh311==1 |mh312==1
label variable gad_b "difficult to control worry"
egen gad_c = anycount (mh314 mh315 mh316 mh317 mh318 mh319 mh320), values (1)
label variable gad_c "number of additional anxiety symptoms"
gen gad_diagnosis = (gad_1) & (gad_a) & (gad_b) & (gad_c>=3)
replace gad_diagnosis =. if (mh301==-1)|(mh301>=98&mh302!=1)|mh302>=98|mh303>=99|mh304>=98|mh305>=98
replace gad_diagnosis =. if mh306>=98|mh307>=98|(mh308>=98&mh310>=98)
replace gad_diagnosis =. if mh309>=98&mh311>=98&mh312>=98
label variable gad_diagnosis "Fulfills criteria for Generalised Anxiety Disorder in the last 12 months"
drop gad_1 gad_a gad_b gad_c
rename gad_diagnosis MHcidi_anxiety
label def MHcidi_anxiety 0 "No" 1 "Yes"
label val MHcidi_anxiety MHcidi_anxiety
notes MHcidi_anxiety : fulfills DSM criteria for Generalised Anxiety Disorder based on an episode lasting at least 6 months
notes MHcidi_anxiety : This scale is designed to detect clinially significant cases of Generalized Anxiety Disorder, it is not necessarily ///
sensitive to other types of anxiety disorder
notes MHcidi_anxiety : Proxies or individuals who answer DK/RF to the early questions in the scale are routed past the additional questions required ///
to fulfill criteria for GAD and are subsequently coded as missingdata$gad_1 <- (
(data$mh301 == 1 | data$mh302 == 1) &
(
data$mh304m >= 6 | data$mh304y >= 1 |
data$mh305m >= 6 | data$mh305y >= 1 |
data$mh304 == 3 | data$mh305 == 3
)
)
attr(data$gad_1, "label") <- "period of worry lasting at least 6 months"
data$gad_a <- data$mh306 == 1 & data$mh307 == 1 &
(data$mh308 == 5 | data$mh310 == 1)
attr(data$gad_a, "label") <- "severe worry"
data$gad_b <- data$mh309 == 1 | data$mh311 == 1 | data$mh312 == 1
attr(data$gad_b, "label") <- "difficult to control worry"
gad_c_items <- paste0("mh", 314:320)
data$gad_c <- rowSums(
sapply(gad_c_items, function(v) data[[v]] == 1),
na.rm = TRUE
)
attr(data$gad_c, "label") <- "number of additional anxiety symptoms"
data$gad_diagnosis <- as.numeric(
data$gad_1 & data$gad_a & data$gad_b & data$gad_c >= 3
)
# Missing rules from the Stata source.
c1 <- (data$mh301 == -1) |
((is.na(data$mh301) | data$mh301 >= 98) &
(is.na(data$mh302) | data$mh302 != 1)) |
(is.na(data$mh302) | data$mh302 >= 98) |
(is.na(data$mh303) | data$mh303 >= 99) |
(is.na(data$mh304) | data$mh304 >= 98) |
(is.na(data$mh305) | data$mh305 >= 98)
c2 <- (is.na(data$mh306) | data$mh306 >= 98) |
(is.na(data$mh307) | data$mh307 >= 98) |
((is.na(data$mh308) | data$mh308 >= 98) &
(is.na(data$mh310) | data$mh310 >= 98))
c3 <- (is.na(data$mh309) | data$mh309 >= 98) &
(is.na(data$mh311) | data$mh311 >= 98) &
(is.na(data$mh312) | data$mh312 >= 98)
data$gad_diagnosis[c1 %in% TRUE | c2 %in% TRUE | c3 %in% TRUE] <- NA_real_
attr(data$gad_diagnosis, "label") <-
"Fulfills criteria for Generalised Anxiety Disorder in the last 12 months"
data$gad_1 <- NULL
data$gad_a <- NULL
data$gad_b <- NULL
data$gad_c <- NULL
names(data)[names(data) == "gad_diagnosis"] <- "MHcidi_anxiety"
attr(data$MHcidi_anxiety, "labels") <- c("No" = 0, "Yes" = 1)
attr(data$MHcidi_anxiety, "note") <- paste(
"fulfills DSM criteria for Generalised Anxiety Disorder based on an episode lasting at least 6 months.",
"This scale is designed to detect clinically significant cases of Generalized Anxiety Disorder;",
"it is not necessarily sensitive to other types of anxiety disorder.",
"Proxies or individuals who answer DK/RF to early questions are routed past additional questions",
"required to fulfill criteria for GAD and are subsequently coded as missing."
)COMPUTE gad_1 =
(mh301 = 1 OR mh302 = 1) AND
(mh304m >= 6 OR mh304y >= 1 OR mh305m >= 6 OR mh305y >= 1
OR mh304 = 3 OR mh305 = 3).
VARIABLE LABELS gad_1 "period of worry lasting at least 6 months".
COMPUTE gad_a = mh306 = 1 AND mh307 = 1 AND (mh308 = 5 OR mh310 = 1).
VARIABLE LABELS gad_a "severe worry".
COMPUTE gad_b = mh309 = 1 OR mh311 = 1 OR mh312 = 1.
VARIABLE LABELS gad_b "difficult to control worry".
COUNT gad_c = mh314 mh315 mh316 mh317 mh318 mh319 mh320 (1).
VARIABLE LABELS gad_c "number of additional anxiety symptoms".
COMPUTE gad_diagnosis = gad_1 AND gad_a AND gad_b AND gad_c >= 3.
IF (
mh301 = -1 OR
((MISSING(mh301) OR mh301 >= 98) AND (MISSING(mh302) OR mh302 <> 1)) OR
MISSING(mh302) OR mh302 >= 98 OR
MISSING(mh303) OR mh303 >= 99 OR
MISSING(mh304) OR mh304 >= 98 OR
MISSING(mh305) OR mh305 >= 98
) gad_diagnosis = $SYSMIS.
IF (
MISSING(mh306) OR mh306 >= 98 OR
MISSING(mh307) OR mh307 >= 98 OR
((MISSING(mh308) OR mh308 >= 98) AND (MISSING(mh310) OR mh310 >= 98))
) gad_diagnosis = $SYSMIS.
IF (
(MISSING(mh309) OR mh309 >= 98) AND
(MISSING(mh311) OR mh311 >= 98) AND
(MISSING(mh312) OR mh312 >= 98)
) gad_diagnosis = $SYSMIS.
VARIABLE LABELS gad_diagnosis
"Fulfills criteria for Generalised Anxiety Disorder in the last 12 months".
DELETE VARIABLES gad_1 gad_a gad_b gad_c.
RENAME VARIABLES (gad_diagnosis = MHcidi_anxiety).
VALUE LABELS MHcidi_anxiety 0 "No" 1 "Yes".
* Notes from the Stata source:
* Fulfills DSM criteria for Generalised Anxiety Disorder based on an episode
* lasting at least 6 months.
* Designed to detect clinically significant cases of GAD; not necessarily
* sensitive to other anxiety disorders.
* Proxies/DK/RF routed past additional questions are subsequently missing.
EXECUTE.