Assessment of Quality of Life 8-Dimension (AQoL-8D): translation, validation, and application in two Dutch trials in patients with epilepsy and schizophrenia

Figures & data

Table 1. Summary statistics of EQ-5D-5L, EQ-VAS, and AQoL-8D utility valuations, percent achieving worst and best health states, effect size (ES), and standardized response mean (SRM) for responsiveness

	Epilepsy (n = 103)			Schizophrenia (n = 99)
	EQ-5D-5L (Utility)	EQ-5D-5L (VAS)	AQoL-8D	EQ-5D-5L (Utility)	EQ-5D-5L (VAS)	AQoL-8D
Mean (SD)	0.82 (0.16)	74.74 (16.11)	0.64 (0.20)	0.75 (0.18)	68.21 (17.34)	0.59 (0.18)
Median (IQR)	0.83 (0.26)	80.00 (20)	0.66 (0.32)	0.80 (0.16)	70.00 (20)	0.56 (0.25)
Minimum	0.12	30.00	0.24	0.15	5.00	0.20
% on floor	0.00	0.00	0.00	0.00	0.00	0.00
Maximum	1.00	100	0.95	1.00	100	0.99
% on ceiling	26.20	3.90	0.00	6.10	1.00	0.00
ES	−0.08	0.36	−0.45	−0.59	−0.31	−0.59
SRM	−0.16	−0.12	−0.51	−0.49	−0.31	−0.59

Abbreviations: EQ-5D-5L, EuroQoL-5 Dimension-5 Level; VAS, Visual Analogue Scale; AQoL-8D, Assessment of Quality of Life 8 Dimension; SD, standard deviation; IQR, interquartile range; ES, effect size; SRM, standardized response mean.

Figure 1. (a) Bland-Altman plot of differences for utility sores between EQ-5D-5L and AQoL-8D in the epilepsy study, (n = 53); (b) Bland-Altman plot of differences for utility sores between EQ-5D-5L and AQoL-8D in the schizophrenia study, (n = 73)

Table 2. Construct validity for clinical groups in the epilepsy study

Variables used to differentiate groups	Groups		Utility instruments
			EQ-5D-5L (Utility)	EQ-5D-5L (VAS)	AqoL-8D
Age categories	18–40 (n = 51)	Mean utility score (SD)	0.84 (0.03)	76.9 (2.32)	0.61 (0.04)
	40+ (n = 51)		0.81 (0.03)	72.1 (2.32)	0.68 (0.04)
		P-value	0.47	0.11	0.15
HADS cases	No (n = 29)	Mean Utility score (SD)	0.94 (0.02)	82.03 (2.83)	0.80 (0.04)
	Yes (n = 62)		0.83 (0.02)	71.66 (1.94)	0.59 (0.03)
		P-value	0.01*	0.00*	0.00*
Number of AEDs	Low (n = 63)	Mean Utility score (SD)	0.86 (0.02)	71.33 (2.72)	0.66 (0.03)
	High (n = 36)		0.78 (0.03)	76.73 (2.05)	0.62 (0.04)
		P-value	0.03*	0.12	0.45
Number of seizures	Low (n = 84)	Mean Utility score (SD)	0.84 (0.02)	75.29 (1.84)	0.65 (0.03)
	High (n = 18)		0.79 (0.04)	71.61 (3.88)	0.61 (0.08)
		P-value	0.31	0.39	0.63

*Indicates statistically significance. Abbreviation: EQ-5D-5L, EuroQoL-5 Dimension- 5 Level; VAS, Visual Analogue Scale; AqoL-8D, Assessment of Quality of Life 8 dimension; SD, standard deviation; HADS, Hospital Anxiety Depression Scale; AEDs, anti-epileptic drugs.

Table 3. Construct validity for clinical groups in the schizophrenia study

Variables used to differentiate groups	Group		Utility instruments
			EQ-5D-5L (Utility)	EQ-5D-5L (VAS)	AQoL-8D
Age	18–24 (n = 45)	Mean Utility score (SD)	0.75 (0.03)	70.65 (2.47)	0.60 (0.03)
	25–44 (n = 54)		0.75 (0.03)	66.28 (2.95)	0.58 (0.03)
		P-value	0.91	0.28	0.58
Use of AP medication	No (n = 8)	Mean Utility score (SD)	0.82 (0.02)	69.00 (11.18)	0.62 (0.09)
	Yes (n = 89)		0.74 (0.02)	68.14 (1.96)	0.59 (0.02)
		P-value	0.24	0.91	0.70
PANNS negative	Low (n = 57)	Mean Utility score (SD)	0.74 (0.03)	69.57 (2.70)	0.61 (0.03)
	High (n = 41)		0.76 (0.03)	65.41 (2.82)	0.56 (0.03)
		P-value	0.63	0.31	0.27
PANNS positive	Low (n = 62)	Mean Utility score (SD)	0.76 (0.03)	68.25 (2.57)	0.62 (0.03)
	High (n = 35)		0.72 (0.04)	67.44 (3.08)	0.54 (0.03)
		P-value	0.38	0.85	0.05*
PANNS general	Low (n = 49)	Mean Utility score (SD)	0.79 (0.02)	71.29 (2.83)	0.65 (0.03)
	High (n = 48)		0.70 (0.03)	64.68 (2.73)	0.54 (0.03)
		P-value	0.02*	0.10	0.01*

*Indicates statistically significance. Abbreviations: EQ-5D-5L, EuroQoL58 Dimension-5 Level; VAS, Visual Analogue Scale; AQoL-8D, Assessment of Quality of Life 8 Dimension; SD, standard deviation; AP, antipsychotics; PANNS, Positive and Negative Syndrome Scale.

Data availability statement

Due to privacy regulations, data will not be made publicly available.