Psychometric Validation of the Ultrashort Slovenian (OHIP-SVN5) and Croatian (OHIP-CRO5) Oral Health Impact Profile Questionnaires

Figure 1.

Inter-item correlation matrix of the OHIP-SVN5 and the OHIP-CRO5_

OHIP-SVN5 Inter-item Correlation Matrix	Difficulty chewing	Painful aching	Uncomfortable with appearance	Less flavour in food	Difficulty doing usual jobs
Difficulty chewing	1.000
Painful aching	0.464	1.000
Uncomfortable with appearance	0.536	0.361	1.000
Less flavour in food	0.447	0.280	0.428	1.000
Difficulty doing usual jobs	0.409	0.356	0.388	0.556	1.000
OHIP-CRO5 Inter-item Correlation Matrix
Difficulty chewing	1.000
Painful aching	0.424	1.000
Uncomfortable about appearance	0.412	0.231	1.000
Less flavour in food	0.469	0.339	0.351	1.000
Difficulty doing usual jobs	0.369	0.315	0.240	0.516	1.000

Age, gender and research purpose of the respondents answering five questions of the Oral Health Impact Profile (OHIP-5)_

Sample	n (% female)	Mean age (standard deviation)	Age range (years)	Research purpose
General population SVN†	400 (72.8)	53.8 (9.7)	28–70	Internal consistency, EFA, Concurrent validity, Known group validity
General population CRO*	223 (65.5)	59.96 (14.6)	28–82	Internal consistency, EFA, Concurrent validity, Known group validity
Students SVN§	38 (68.4)	22.6 (1.7)	20–26	Test-retest reliability
Students CRO‡	30 (70.0)	22.0 (1.4)	19–25	Test-retest reliability
Patients with treatment needs SVN#	30 (54.0)	50.8 (14.2)	18–70	Responsiveness (sensitivity to change)
Patients with treatment needs CRO‡	30 (65.0)	65.5 (10.4)	37–81	Responsiveness (sensitivity to change)

Concurrent validity of the Slovenian and Croatian OHIP-5 Questionnaires_

General population SVN (n=400)
Self-reported oral health	n	OHIP-5 summary score	Spearman’s rho
excellent	51	0.69 (1.16)	0.601**
good	224	1.86 (2.06)
fair	94	4.33 (3.38)
poor	31	7.77 (3.81)
Self-reported oral aesthetics	n	OHIP-5 summary score	Spearman’s rho
excellent	52	1.12 (1.71)	0.510**
good	213	1.83 (2.12)
fair	106	3.99 (3.17)
poor	29	7.90 (4.29)

Factor loadings of one dimension of the OHIP-5 questionnaire_

Item	OHIP-SVN5	OHIP-CRO5
	One component
Difficulty chewing	0.787	0.774
Painful aching	0.651	0.642
Uncomfortable about appearance	0.744	0.611
Less flavour in food	0.744	0.780
Difficulty doing usual jobs	0.740	0.699

Means, standard deviations and Cronbach’s alpha when the item was deleted from the OHIP-SVN5 and OHIP-CRO5 questionnaires_

OHIP-5 item	OHIP-SVN5			OHIP-CRO5
	Mean	Standard deviation	Cronbach’s alpha if the item is deleted	Mean	Standard deviation	Cronbach’s alpha if the item is deleted
Difficulty chewing	0.97	1.10	0.69	0.87	1.04	0.60
Painful aching	0.67	0.85	0.74	0.41	0.76	0.67
Uncomfortable with appearance	0.70	1.08	0.71	0.82	1.03	0.70
Less flavour in food	0.24	0.64	0.73	0.25	0.53	0.64
Difficulty doing usual jobs	0.18	0.56	0.74	0.17	0.49	0.68

Known-groups validity, assessed by the Mann-Whitney U test_

OHIP-SVN5	Denture (Fixed and Removable)	N	Mean	Standard Deviation	Z	P
Difficulty chewing	no	304	0.74	0.93	−7.020	<0.001**
	yes	96	1.70	1.24
Painful aching	no	304	0.57	0.79	−4.174	<0.001**
	yes	96	0.98	0.94
Uncomfortable about appearance	no	304	0.53	0.93	−4.910	<0.001**
	yes	96	1.23	1.34
Less flavour in food	no	304	0.14	0.49	−5.262	<0.001**
	yes	96	0.54	0.92
Difficulty doing usual jobs	no	304	0.12	0.46	−3.214	<0.001**
	yes	96	0.34	0.80
OHIP-SVN5	no	304	2.10	2.56	−7.080	<0.001**
summary score	yes	96	4.80	3.86

Test-retest reliability measured by intraclass correlation coefficients (ICC) of the Slovenian and Croatian versions of the 5-item Oral Health Impact Profile (OHIP-SVN5 and OHIP-CRO5)_

OHIP-SVN5: Students (n=38)	ICC	Mean difference (standard deviation)	95% confidence interval	P
Difficulty chewing	0.74	−0.03 (0.43)	−0.169 – 0.12	0.711 N.S.
Painful aching	0.65	0.105 (0.61)	−0.093 – 0.30	0.291 N.S.
Uncomfortable about appearance	0.82	0.105 (0.45)	−0.043 – 0.25	0.160 N.S.
Less flavour in food	N.C.	0 (0)	N.C.	N.C.
Difficulty doing usual jobs	0.70	−0.026 (0.60)	−.080 – 0.03	0.324 N.S.
Summary score	0.82	0.157 (0.89)	−0.133 – 0.45	0.279 N.S.

Sensitivity to change (responsiveness) of the OHIP-SVN5 (N=30) and OHIP-CRO5 (N=30), pre- versus post-treatment_

	Pre-treatment x±SD	Post-treatment x±SD	Mean difference x±SD	Z	P	Effect size
OHIP-SVN5
Difficulty chewing	2.33±0.96	1.87±0.82	0.47±0.68	−2.64	0.008**	0.48
Painful aching	2.70±1.02	1.90±0.71	0.80±0.99	−3.67	0.001**	0.78
Uncomfortable about appearance	1.90±0.84	1.96±0.98	0.06±0.69	−0.58	0.564 N.S.	0.07
Less flavour in food	1.43±0.73	1.23±0.50	0.20±0.55	−1.90	0.056 N.S.	0.28
Difficulty doing usual jobs	1.47±0.63	1.20±0.41	0.27±0.58	−2.31	0.021*	0.43
Summary score	9.83±2.29	8.03±1.73	1.80±1.40	−4.53	<0.001**	0.79
OHIP-CRO5
Difficulty chewing	2.67±1.23	1.57±1.33	1.10±1.44	−3.35	0.001**	0.89
Painful aching	0.53±1.04	0.17±0.38	0.37±0.89	−2.31	0.021*	0.35
Uncomfortable about appearance	2.60±1.40	0.87±1.17	1.73±1.55	−4.10	<0.001**	1.24
Less flavour in food	0.80±1.19	0.40±0.89	0.40±0.81	−2.44	0.015*	0.34
Difficulty doing usual jobs	0.77±1.10	0.20±0.61	0.57±0.94	−2.85	0.004**	0.52
Summary score	7.37±4.06	3.20±3.28	4.17±0.74	−4.25	<0.001**	1.03