Table 3.

Clinical and demographic information for healthy volunteers and participants with OCD

	OCD (M ± SD)	HV (M ± SD)	t-test	DF	p	d	95% CI
N	31	30
Age (years)	30.79 ± 9.99	32.16 ± 12.98	−0.46	59	0.64	−0.12	[−7.29, 4.55]
Gender (% female)	55%	50%	0.143 ${}^{{\mathrm{X}}^2}$	1	0.70	−0.05 Phi	[0.30, 2.25]
Education (years)	15.35 ± 2.85	17.23 ± 2.72	−2.62	59	0.01	−0.67	[−3.31, −0.44]
Verbal IQ	110.21 ± 6.13	113.11 ± 7.75	−1.62	59	0.11	−0.41	[−6.48, 0.67]
MADRS	17.65 ± 11.01	5.07 ± 3.78	6.00	37.20	<0.001	1.52	[8.33, 16.82]
STAI-S	37.65 ± 9.12	27.70 ± 6.83	4.80	59	<0.001	1.23	[5.80, 14.08]
STAI-T	56.55 ± 11.03	37.13 ± 10.80	6.94	59	<0.001	1.77	[13.81, 25.01]
YBOCS total	22.94 ± 5.90	NA	NA	NA	NA	NA	NA
YBOCS obsessions	11.45 ± 3.21	NA	NA	NA	NA	NA	NA
YBOCS compulsions	11.52 ± 2.97	NA	NA	NA	NA	NA	NA
OCI total	63.32 ± 30.37	6.07 ± 5.80	924U	NA	<0.001	−0.73${}^{{\mathrm{\eta }}_{\mathrm{p}}{}^2}$	[45.0, 66.0]
OCI washing	10.48 ± 9.86	1.00 ± 1.39	793U	NA	<0.001	−0.38${}^{{\mathrm{\eta }}_{\mathrm{p}}{}^2}$	[2.0, 11.0]
OCI checking	13.06 ± 8.28	1.23 ± 1.45	868U	NA	<0.001	−0.58${}^{{\mathrm{\eta }}_{\mathrm{p}}{}^2}$	[9.0, 14.0]
OCI doubting	6.26 ± 3.56	0.23 ± 0.62	874U	NA	<0.001	−0.63${}^{{\mathrm{\eta }}_{\mathrm{p}}{}^2}$	[4.0, 9.0]
OCI ordering	7.29 ± 5.24	1.30 ± 1.49	836U	NA	<0.001	−0.48${}^{{\mathrm{\eta }}_{\mathrm{p}}{}^2}$	[3.0, 7.0]
OCI obsessions	14.42 ± 8.11	0.73 ± 1.20	896U	NA	<0.001	−0.66${}^{{\mathrm{\eta }}_{\mathrm{p}}{}^2}$	[11.0, 16.0]
OCI hoarding	3.16 ± 2.86	0.93 ± 1.72	696U	NA	<0.001	−0.19${}^{{\mathrm{\eta }}_{\mathrm{p}}{}^2}$	[1.0, 3.0]
OCI neutralisation	8.65 ± 5.77	0.73 ± 0.94	878U	NA	<0.001	−0.60${}^{{\mathrm{\eta }}_{\mathrm{p}}{}^2}$	[4.0, 10.0]
IUS	84.61 ± 22.85	54.37 ± 16.93	5.88	59	<0.001	1.50	[19.91, 40.58]
HTQ compulsivity	23.87 ± 4.21	13.60 ± 5.56	8.15	59	<0.001	2.08	[7.75, 12.81]

The sample size for OCI in healthy group is 28 because two participants did not provide these data, for the rest of the data there were 30 healthy subjects and 31 participants with OCD. The tests used for age, gender, education and verbal IQ were two-sided, and the rest of the variables were tested using a one-sided test. The data for this table are provided in the Source Data file.

NA Not Applicable, CI Confidence Interval, MADRS Montgomery- Asberg Depression Rating Scale, STAI-T State Trait Anxiety Inventory- Trait, STAI-S State Trait Anxiety Inventory- State, YBOCS Yale Brown Obsessive Compulsive Scale, OCI Obsessive-Compulsive Inventory, IUS Intolerance of Uncertainty Scale, HTQ Habitual Tendencies Questionnaire, HV healthy volunteers, OCD obsessive compulsive disorder, DF degree of freedom, U Mann–Whitney U test for not normally distributed data, X² Chi-Square test for categorical data, η_p² partial eta-square (a measure of effect size for the U test), Phi a measure of effect size for the X² test, d Cohen’s d, CI Confidence Interval of the t-test.