Development and validation of a screening instrument for bipolar spectrum disorder: The Mood Disorder Questionnaire Thai version

Figures & data

Table 1 Sample description (N=250)

Items	Mean ± SD or number (%)
Age (years)	46.9±13.8
Sex
Men	52 (20.8%)
Women	198 (79.2%)
Marital status
Single	80 (32%)
Married	131 (52.4%)
Divorced	16 (6.4%)
Widow(er)	16 (6.4%)
Living as married	7 (2.8%)
Education
No education	6 (2.4%)
Elementary school	46 (18.4%)
High school	72 (28.8%)
College degree	92 (36.8%)
Graduate degree	29 (11.6%)
Other	5 (2.0%)
Employment
Unemployed	72 (28.8%)
Full time	131 (52.4%)
Part time	9 (3.6%)
Retired	30 (12.0%)
Other	8 (3.2%)
Illness characteristics
Age of onset (years)	39.2±12.9
Illness duration (years)	7.8±8.0 (median =5)

Abbreviation: SD, standard deviation.

Table 2 Question #1 item-level values and item-total correlation for the Thai version of the MDQ (N=250)

MDQ question #1 items	Percentages of patients who endorsed each item		Corrected item-total correlation	Cronbach’s alpha if item deleted
	Major depressive disorder (N=190)	Bipolar disorder (N=60)
A. You felt so good or so hyper that other people thought you were not your normal self, or you were not your normal self, or you were so hyper that you got into trouble?	10.0	48.3	0.44	0.78
B. You were so irritable that you shouted at people or started fights or arguments?	25.8	71.7	0.29	0.79
C. You felt much more self-confident than usual?	18.4	55.0	0.52	0.77
D. You got much less sleep than usual and found you didn’t really miss it?	33.2	66.7	0.34	0.79
E. You were much more talkative or spoke faster than usual?	15.3	48.3	0.49	0.77
F. Thoughts raced through your head or you couldn’t slow your mind down?	23.7	63.3	0.56	0.76
G. You were so easily distracted by things around you that you had trouble concentrating or staying on track?	43.2	75.0	0.39	0.78
H. You had much more energy than usual?	10.5	45.0	0.57	0.76
I. You were much more active or did many more things than usual?	21.1	46.7	0.54	0.77
J. You were much more social or outgoing than usual; for example, you telephoned friends in the middle of the night?	2.6	18.3	0.35	0.78
K. You were much more interested in sex than usual?	3.2	10.0	0.24	0.79
L. You did things that were unusual for you or that other people might have thought were excessive, foolish, or risky?	17.9	53.3	0.47	0.77
M. Spending money got you or your family into trouble?	12.6	35.0	0.28	0.79

Abbreviation: MDQ, Mood Disorder Questionnaire.

Figure 1 Sensitivity and specificity of the MDQ for bipolar disorder at different cutoffs.

Notes: Area under the curve was 0.82 (95% confidence interval: 0.70–0.90, P<0.0001).
Abbreviation: MDQ, Mood Disorder Questionnaire.

Table 3 Sensitivity, specificity, PPV, NPV, and LR of the Thai version of the MDQ for diagnosis of bipolar disorder

Cutoff points	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	Positive LR	Negative LR
>3	94.1	45.5	64.0	88.2	1.7	0.1
>4	85.3	51.5	64.4	77.3	1.8	0.3
>5	76.5	72.7	74.3	75.0	2.8	0.3
>6	58.8	87.9	83.3	67.4	4.9	0.5
>7	47.1	90.9	84.2	62.5	5.2	0.6
>8	32.4	93.9	84.6	57.4	5.3	0.7
>9	17.7	97.0	85.7	53.3	5.8	0.9

Abbreviations: LR, likelihood ratio; MDQ, Mood Disorder Questionnaire; NPV, negative predictive value; PPV, positive predictive value.