Psychometric evaluation of the Swedish translation of the revised Cystic Fibrosis Questionnaire in adults

Figures & data

Table 1. Descriptive statistics for the 12 CFQ-R scales.

Scales	M	SD	Median	1st Quartile	3rd Quartile	Skewness	Kurtosis	Floor effects: % with score ≤5	Ceiling effects: % with score ≥95
Physical functioning	82.27	22.92	91.67	75.00	100.00	−1.56*	1.75*	0.60	46.20
Vitality	59.92	20.40	66.67	41.67	75.00	−0.40*	−0.27	0.60	1.70
Emotional functioning	77.19	19.02	80.00	66.67	93.33	−0.87*	0.18	0	15.00
Eating disturbances	89.53	16.63	100.00	88.89	100.00	−2.17*	5.90*	0	57.80
Treatment burden	62.30	20.21	66.67	55.55	77.78	−0.09	−0.11	0	8.10
Health perceptions	63.20	23.46	66.67	44.44	77.78	−0.53*	−0.16	2.30	7.50
Social functioning	76.52	15.54	77.78	66.67	88.88	−0.83*	0.52	0	5.20
Body image	77.65	23.60	88.88	66.67	100.00	−1.31*	1.38*	1.70	27.70
Role limitations	83.67	19.88	91.67	75.00	100.00	−1.57*	2.21*	0	35.30
Weight problems	72.64	36.43	100.00	33.33	100.00	−0.96*	−0.57*	12.70	57.20
Respiratory symptoms	70.42	20.21	72.22	55.55	88.88	−0.54*	−0.44	0	6.90
Digestive symptoms	78.29	17.52	77.77	66.67	88.88	−0.84*	0.60	0	20.20

*P < .05.

Table 2. Reliabilities for the 12 CFQ-R scales.

Scales	Cronbach alpha coefficient	Intra-class correlation coefficients (95% CI)
Physical functioning	0.93	0.96*** (0.91, 0.98)
Vitality	0.72	0.84*** (0.66, 0.93)
Emotional functioning	0.75	0.89*** (0.76, 0.95)
Eating disturbances	0.82	0.80*** (0.56, 0.91)
Treatment burden	0.56	0.71*** (0.36, 0.87)
Health perceptions	0.75	0.92*** (0.82, 0.96)
Social functioning	0.53	0.91*** (0.80, 0.96)
Body image	0.62	0.86*** (0.68, 0.94)
Role limitations	0.79	0.89*** (0.75, 0.95)
Weight problems	n.a.	0.88*** (0.74, 0.95)
Respiratory symptoms	0.85	0.74*** (0.42, 0.88)
Digestive symptoms	0.63	0.88*** (0.74, 0.95)

n.a. = not applicable (single-item scale).

***P < .001.

Table 3. Comparisons between the three severity groups for the 12 CFQ-R scales.^a

	Mildly impaired (n = 101)		Moderately impaired (n = 53)		Severely impaired (n = 19)				Cohen’s d (Tamhane’s T2 post hoc test)
Scales	M	SD	M	SD	M	SD	F2, 170	η^2^a	Mildly versus Moderately impaired	Mildly versus Severely impaired	Moderately versus Severely impaired
Physical functioning	91.13	12.41	75.16	26.26	55.04	28.28	31.96***	0.27	0.78***	1.65***	0.74*
Vitality	62.13	19.70	58.49	21.89	52.19	18.39	2.11	0.02	0.17 (n.s.)	0.52 (n.s.)	0.31 (n.s.)
Emotional functioning	78.22	17.98	77.11	20.78	71.92	19.45	0.87	0.01	0.06 (n.s.)	0.34 (n.s.)	0.26 (n.s.)
Eating disturbances	91.53	14.24	85.95	20.80	88.89	14.34	1.99	0.02	0.31 (n.s.)	0.11 (n.s.)	−0.16 (n.s.)
Treatment burden	66.34	19.34	58.91	19.92	50.30	20.07	6.50**	0.07	0.38 (n.s.)	0.81**	0.43 (n.s.)
Health perceptions	69.53	20.94	56.39	22.84	48.54	27.02	10.69***	0.11	0.60**	0.87**	0.31 (n.s.)
Social functioning	79.81	13.05	72.64	17.15	69.88	19.00	5.98**	0.07	0.47*	0.61 (n.s.)	0.15 (n.s.)
Body image	82.40	20.38	75.89	22.41	57.31	31.48	10.24***	0.11	0.30 (n.s.)	0.95**	0.68 (n.s.)
Role limitations	87.13	17.02	82.39	19.24	68.86	28.17	7.43***	0.08	0.26 (n.s.)	0.78*	0.56 (n.s.)
Weight problems	81.18	31.42	66.04	37.83	45.61	41.88	9.79***	0.10	0.44*	0.96**	0.51 (n.s.)
Respiratory symptoms	77.06	17.44	61.53	20.41	59.94	20.33	15.33***	0.15	0.82***	0.35**	0.08 (n.s.)
Digestive symptoms	76.68	17.25	80.71	17.72	80.12	18.36	1.04	0.01	−0.23 (n.s.)	−0.19 (n.s.)	0.02 (n.s.)

^aSmall effect size in ordinary type; medium in italics; large in bold.

n.s. = not significant (P > .05); *P < .05; **P < .01; ***P < .001.

Table 4. Comparisons between nourished and malnourished for the 12 CFQ-R scales.^a

	Nourished (n = 152)		Malnourished (n = 21)
Scales	M	SD	M	SD	F1, 171	η^2	Cohen’s d
Physical functioning	83.66	22.50	72.22	23.95	4.69*	0.03	0.49
Vitality	60.31	20.29	57.14	21.45	0.44	0.00	0.15
Emotional functioning	77.15	18.71	77.46	21.65	0.00	0.00	−0.02
Eating disturbances	91.08	12.98	78.31	30.93	11.55***	0.06	0.54
Treatment burden	62.35	19.94	61.90	22.65	0.01	0.00	0.02
Health perceptions	63.45	23.22	61.38	25.73	0.14	0.00	0.08
Social functioning	77.08	14.86	72.49	19.76	1.62	0.01	0.26
Body image	80.99	20.28	53.44	31.35	29.29***	0.15	1.04
Role limitations	83.66	20.02	83.73	19.27	0.00	0.00	−0.00
Weight problems	77.63	32.73	36.51	42.04	27.08***	0.14	1.09
Respiratory symptoms	71.05	20.30	65.87	19.35	1.21	0.01	0.26
Digestive symptoms	78.22	17.53	78.84	17.88	0.02	0.00	−0.04

^a Small effect size in ordinary type; medium in italics; large in bold.

*P < .05; ***P < .001.

Table 5. Comparisons between young adults and adults for the 12 CFQ-R scales.^a

	Young adults (n = 81)		Adults (n = 92)
Scales	M	SD	M	SD	F1, 171	η^2	Cohen’s d
Physical functioning	88.42	16.12	76.86	26.48	11.65***	0.06	0.53
Vitality	61.93	18.86	58.15	21.61	1.48	0.01	0.19
Emotional functioning	77.61	17.01	76.81	20.72	0.08	0.00	0.04
Eating disturbances	89.16	19.48	89.86	13.75	0.07	0.00	−0.04
Treatment burden	61.59	18.09	62.92	21.99	0.19	0.00	−0.07
Health perceptions	66.80	22.67	60.02	23.82	3.65	0.02	0.29
Social functioning	80.73	14.94	72.83	15.20	11.83***	0.06	0.52
Body image	81.62	21.53	74.15	24.88	4.39*	0.02	0.32
Role limitations	85.29	16.10	82.25	22.69	1.01	0.01	0.15
Weight problems	75.72	36.52	69.93	36.33	1.09	0.01	0.16
Respiratory symptoms	74.00	17.89	67.27	21.66	4.89*	0.03	0.34
Digestive symptoms	76.95	19.31	79.47	15.79	0.89	0.00	−0.14

^a Small effect size in ordinary type; medium in italics; large in bold.

*P < .05; ***P < .001.

Table 6. Comparisons between men and women for the 12 CFQ-R scales.^a

	Men (n = 89)		Women (n = 84)
Scales	M	SD	M	SD	F1, 171	η^2	Cohen’s d
Physical functioning	82.68	23.78	81.84	22.11	0.06	0.00	0.04
Vitality	61.61	19.97	58.13	20.82	1.26	0.01	0.17
Emotional functioning	79.03	18.92	75.24	19.04	1.72	0.01	0.20
Eating disturbances	89.89	14.47	89.15	18.73	0.08	0.00	0.04
Treatment burden	64.54	20.09	59.92	20.19	2.28	0.01	0.23
Health perceptions	63.29	24.24	63.09	22.76	0.00	0.00	0.01
Social functioning	77.15	15.57	75.86	15.58	0.30	0.00	0.08
Body image	72.66	26.86	82.94	18.29	8.56**	0.05	−0.45
Role limitations	83.61	19.72	83.73	20.16	0.00	0.00	−0.01
Weight problems	63.67	38.48	82.14	31.66	11.81***	0.06	−0.52
Respiratory symptoms	70.91	21.09	69.91	19.34	0.11	0.00	0.05
Digestive symptoms	79.28	17.42	77.25	17.67	0.58	0.00	0.12

^a Small effect size in ordinary type; medium in italics; large in bold.

**P < .01; ***P < .001.