Validation of the Lymphoedema Quality of Life Questionnaire (LYMQOL) in Swedish cancer patients

Figures & data

Table 1. Descriptive data of the study population in the validation of the Swedish versions of LYMQOL for arm and leg.

		LYMQOL version
		Arm (n = 52)	Leg (n = 50)
Age (years)		62 (34–75)	61 (34–82)
Gender	Female	51 (98%)	47 (94%)
	Male	1 (2%)	3 (6%)
Duration of lymphoedema (years)		2.0 (0.1–20)	1.5 (0.2–33)
Affected limbs (no. of persons)	Unilateral	52 (100%)	24 (48%)
	Bilateral	0 (0%)	26 (52%)
Degree of lymphoedema* (right side):	None	26 (50%)	9 (18%)
	A little	12 (23%)	20 (40%)
	Quite a bit	13 (25%)	17 (34%)
	A lot	1 (2%)	4 (8%)
Degree of lymphoedema* (left side):	None	27 (52%)	15 (30%)
	A little	11 (21%)	15 (30%)
	Quite a bit	13 (25%)	13 (26%)
	A lot	1 (2%)	7 (14%)

Figures denote median and range or number and per cent.

^* Patient reported severity of the lymphoedema.

Table 2. Summary results of the face - and content validity survey with six items of the Swedish arm and leg versions of the LYMQOL.

		LYMQOL version
		Arm (n = 52)		Leg (n = 50)
Item	Question in the survey	Yes	No	Yes	No
A	Was the form easy to answer?	49 (94%)	3 (6%)	50 (100%)	–
B	Too many questions in the form?	–	52 (100%)	2 (4%)	48 (96%)
C	Were the questions clear?	48 (92%)	4 (8%)	43 (86%)	7 (14%)
D	Was there any important areas of lymphoedema that might have an impact on QOL that had not been covered in the LYMQOL form?	7 (13%)	45 (87%)	14 (28%)	36 (72%)
E	Did you think any item in the form was unnecessary?	–	52 (100%)	2 (4%)	48 (96%)
F	Comments to the questionnaire?	8 (15%)	44 (85%)	6 (12%)	44 (88%)

Table 3. Construct validity of the Swedish version of the LYMQOL.

	LYMQOL version
	Arm								Leg
	SF-36 domain
	PCS				MCS				PCS					MCS
	Timing of filling in the questionnaire
	First occasion		Second occasion		First occasion		Second occasion		First occasion		Second occasion		First occasion			Second occasion
LYMQOL domain	rs	p-value	rs	p-value	rs	p-value	rs	p-value	rs	p-value	rs	p-value	rs		p-value	rs	p-value
Function	−0.34	.01	−0.37	<.01					−0.79	<.01	−0.82	<.01
Body image/appearance					−0.28	.05	−0.26	.02					−0.41		<.01	−0.49	<.01
Symptom	−0.50	<.01	−0.29	.04					−0.70	<.01	−0.75	<.01
Mood					−0.66	<.01	−0.60	<.01					−0.53		<.01	−0.52	<.01

r_s: Spearman’s correlation coefficient (rho). Correlations between LYMQOL domains Function and Symptom and the SF-36 physical component summary (PCS) and the LYMQOL domains Body image/appearance and Mood and the SF-36 mental component summary (MCS), respectively.

Table 4. Test-retest reliability.

	LYMQOL version
	Arm						Leg
	Occasion							Occasion
	First	Second						First	Second
Domain	Mean score	Mean score	ICC	p-value	Difference means	SEM	SRD	Mean score	Mean score	ICC	p-value	Difference means	SEM	SRD
Function	1.33	1.31	0.85	<.01	0.02	1.04	2.89	1.67	1.64	0.78	<.01	0.03	2.00	5.54
Body image/appearance	1.52	1.56	0.82	<.01	−0.04	1.69	4.68	1.89	1.84	0.91	<.01	0.05	1.45	4.02
Symptom	1.58	1.70	0.53	<.01	−0.12	3.26	9.04	1.82	1.77	0.88	<.01	0.05	1.64	4.56
Mood	1.42	1.44	0.87	<.01	−0.02	1.43	3.96	1.59	1.55	0.81	<.01	0.04	2.17	6.02
Global score	7.88	7.82	0.65	<.01	0.06	8.09	22.4	7.52	7.48	0.83	<.01	0.04	4.47	12.4

ICC: intra-class correlation coefficient; LYMQOL: Lymphoedema Quality of Life Questionnaire; SEM: standardised error of measurement; SRD: smallest real difference. Intra-class correlations, standardised error of measurement and smallest real difference between LYMQOL domains and occasion of filling in the validation of the Swedish LYMQOL questionnaire versions for arm and leg.

Table 5. Internal consistency in the validation of the Swedish version of the LYMQOL.

	LYMQOL version
	Arm				Leg
	Timing of filling in the questionnaires
	First occasion		Second occasion		First occasion		Second occasion
Domain	Cronbach’s alpha	Number of items	Cronbach’s alpha	Number of items	Cronbach’s alpha	Number of items	Cronbach’s alpha	Number of items
Function	0.79	10	0.86	10	0.91	8	0.92	8
Body image/appearance	0.85	5	0.89	5	0.88	7	0.88	7
Symptom	0.83	6	0.85	6	0.87	5	0.88	5
Mood	0.87	6	0.93	6	0.92	6	0.94	6