Abbreviated Three-Item Versions of the Satisfaction with Life Scale and the Harmony in Life Scale Yield as Strong Psychometric Properties as the Original Scales

Figures & data

Table 1. Descriptive statistics for the SWLS-3 and the HILS-3 scales and items.

Dataset	Variable	Mean	SD	Skew	Kurtosis	Alpha	Item tot. r
1	SWLS-3 total	14.90	4.28	−0.92	0.18	.88	–
	SWLS 1	4.75	1.59	−0.78	−0.18	.85	.88
	SWLS 2	4.93	1.58	−0.79	−0.27	.82	.90
	SWLS 3	5.19	1.60	−1.06	0.30	.81	.91
	HILS-3 total	15.30	3.85	−1.1	0.89	.90	–
	HILS 1	5.20	1.32	−1.12	0.96	.85	.91
	HILS 2	5.12	1.45	−0.98	0.35	.90	.90
	HILS 3	5.04	1.45	−1.00	0.45	.83	.93
2	SWLS-3 total	14.41	5.00	−0.83	−0.41	.94	–
	SWLS 1	4.63	1.78	−0.68	−0.74	.90	.95
	SWLS 2	4.82	1.71	−0.80	−0.45	.93	.93
	SWLS 3	4.97	1.80	−0.93	−0.36	.91	.95
	HILS-3 total	15.03	4.84	−0.95	−0.21	.96	–
	HILS 1	5.12	1.58	−1.00	0.09	.95	.95
	HILS 2	4.99	1.70	−0.92	−0.29	.94	.97
	HILS 3	4.92	1.75	−0.87	−0.45	.94	.97
3	SWLS-3 total	13.09	4.20	−0.47	−0.72	.88	–
	SWLS 1	4.10	1.62	−0.36	−1.10	.83	.90
	SWLS 2	4.43	1.50	−0.44	−0.73	.85	.88
	SWLS 3	4.56	1.57	−0.59	−0.71	.80	.91
	HILS-3 total	13.10	4.15	−0.44	−0.75	.92	–
	HILS 1	4.48	1.41	−0.47	−0.65	.90	.92
	HILS 2	4.42	1.56	−0.47	−0.95	.89	.93
	HILS 3	4.20	1.50	−0.37	−0.85	.86	.94

Note. N = 787 in Dataset 1; N = 860 in Dataset 2; and N = 343 in Dataset 3.

Alpha = Cronbach’s alpha for the entire scales or item level Cronbach’s alpha for when item was dropped. Item tot. r = Item total correlation; SWLS = Satisfaction with life scale; HILS = Harmony in life scale; SWLS 1 = In most ways my life is close to my ideal; SWLS 2 = The conditions of my life are excellent; SWLS 3 = I am satisfied with my life; HILS 1= My lifestyle allows me to be in harmony; HILS 2 = Most aspects of my life are in balance; HILS 3 = I am in harmony.

Table 2. Pearson’s correlations among the scales.

Dataset		SWLS-3	HILS-3	SWLS-5	HILS-5
1	1. SWLS-3	–
	2. HILS-3	.73	–
	3. SWLS-5	.95	.73	–
	4. HILS-5	.75	.96	.74	–
2	1. SWLS-3	–
	2. HILS-3	.85	–
	3. SWLS-5	.97	.84	–
	4. HILS-5	.85	.98	.84	–
3	1. SWLS-3	–	.74	NA	NA
	2. HILS-3	.74	–	NA	NA

Notes. p < .001 for all correlations. N = 787 in Dataset 1; N = 860 in Dataset 2; N = 343 in Dataset 3.

Figure 1. Standardized regression weights for the two-factor model of the Harmony in life (HIL) and the Satisfaction with life (SWL) three-item scales in three different datasets. The first row is Dataset 1 (N = 787); the second row Dataset 2 (N = 860), and the third row Dataset 3 (N = 343). The factor loading of the first item of each latent construct was set to 1.0 to identify the models.

Table 3. CFA results of the SWLS and the HILS show that a 2-factor solution with the shorter scales yield the best fit.

Dataset	Model	Chi^2	p-value	df	CFI	RMSEA
1	5-items
	1-factor	361.647	.000	35	.889	.137
	2-factor	122.407	.000	34	.970	.072
	3-items
	1-factor	199.414	.000	9	.894	.228
	2-factor	37.827	.000	8	.983	.089
2	5-items
	1-factor	485.641	.000	35	.928	.165
	2-factor	105.228	.000	34	.989	.064
	3-items
	1-factor	242.719	.000	9	.945	.251
	2-factor	15.424	.051	8	.998	.043
	3-items
3	1-factor	111.480	.000	9	.927	.224
	2-factor	13.156	.107	8	.996	.052

Notes. N = 787 in Dataset 1; N = 860 in Dataset 2; and N = 343 in Dataset 3.

Estimator = robust Maximum Likelihood (MLM)

SWLS = Satisfaction with life scale; HILS = Harmony in life scale.

Table 4. Results from longitudinal measurement invariance analyses of the SWLS.

D.	Model	χ^2(df)	Δχ^2(df)	p	CFI	ΔCFI	RMSEA	AIC	BIC
1		SWLS-5
	1: Configural	64.3(29)	–	–	.995	–	.039	16254	16408
	2: Loadings	67.0(33)	3.24(4)	.52	.995	.000	.036	16249	16386
	3: Intercepts	67.7(37)	0.74(4)	.95	.995	.001	.031	16242	16362
	4: Residual variances	77.2(42)	7.17(5)	.21	.995	.001	.031	16241	16340
	5: Factor means	79.5(43)	2.44(1)	.12	.994	.000	.032	16241	16336
		SWLS-3
	1: Configural	17.8 (5)	–	–	.996	–	.063	9479	9573
	2: Loadings	19.7(7)	2.002(2)	.37	.996	.000	.053	9477	9562
	3: Intercepts	20.4(9)	0.646(2)	.72	.996	.001	.044	9473	9550
	4: Residual variances	21.9(12)	0.975(3)	.81	.998	.001	.031	9469	9533
	5: Factor means	24.3(13)	2.470(1)	.12	.997	.001	.033	9469	9529
2		SWLS-5
	1: Configural	66.7(29)	–	–	.995	–	.043	13680	13830
	2: Loadings	69.6(33)	2.84(4)	.584	.995	.000	.039	13674	13808
	3: Intercepts	70.7(37)	1.16(4)	.884	.996	.001	.035	13668	13784
	4: Residual variances	87.8(42)	10.87(5)	.054	.994	.002	.039	13675	13771
	5: Factor means	87.9(43)	0.04(1)	.837	.994	.000	.038	13673	13764
		SWLS-3
	1: Configural	6.73(5)	–	–	1	–	.004	8043	8135
	2: Loadings	8.12(7)	1.44(2)	.49	1	0	.000	8041	8124
	3: Intercepts	9.07(9)	0.95(2)	.62	1	0	.000	8038	8113
	4: Residual variances	17.25(12)	4.58(3)	.21	1	0	.015	8040	8103
	5: Factor means	17.26(13)	0.01(1)	.92	1	0	.007	8038	8096
		SWLS-3
3	1: Configural	7.14(5)	–	–	1	–	.010	5296	5378
	2: Loadings	9.85(7)	3.08(2)	.214	.999	.001	.023	5295	5369
	3: Intercepts	10.50(9)	0.66(2)	.718	1	.001	.000	5292	5358
	4: Residual variances	29.89(12)	11.29(3)	.010*	.991	.009	.063	5305	5360
	5: Factor means	29.90(13)	0.01(1)	.922	.991	.001	.058	5303	5355

Notes. N = 535 in Dataset 1; N = 477 in Dataset 2; and N = 299 in Dataset 3.

Estimator = robust Maximum Likelihood (MLM)

D. = Dataset; SWLS = Satisfaction with life scale, where 3 and 5 refer to the number of items.

Table 5. Results from longitudinal measurement invariance analyses of the HILS.

D.	Model	χ^2(df)	Δχ^2(df)	p	CFI	ΔCFI	RMSEA	AIC	BIC
1		HILS-5
	1: Configural	116(29)	–	–	.982	–	.067	14300	14455
	2: Loadings	119(33)	3.29	.51	.983	.000	.062	14296	14433
	3: Intercepts	120(37)	1.04	.90	.983	.001	.057	14289	14409
	4: Residual variances	128(42)	4.72	.45	.983	.000	.054	14287	14386
	5: Factor means	129(43)	0.27	.60	.984	.000	.053	14285	14380
		HILS-3
	1: Configural	1.92(5)	–	–	1	–	0	8532	8626
	2: Loadings	2.21(7)	0.304(2)	.86	1	0	0	8528	8614
	3: Intercepts	2.34(9)	0.131(2)	.94	1	0	0	8524	8601
	4: Residual variances	7.30(12)	2.958(3)	.40	1	0	0	8523	8587
	5: Factor means	7.73(13)	0.428(1)	.51	1	0	0	8521	8581
2		HILS-5
	1: Configural	140(29)	–	–	.984	–	.078	12603	12753
	2: Loadings	146(33)	4.72(4)	.32	.983	.000	.073	12601	12734
	3: Intercepts	147(37)	1.32(4)	.86	.984	.001	.068	12594	12711
	4: Residual variances	152(42)	1.74(5)	.88	.986	.002	.060	12589	12684
	5: Factor means	152(43)	0.06(1)	.81	.986	.000	.059	12587	12678
		HILS-3
	1: Configural	10.9(5)	–	–	.999	NA	.037	7517	7609
	2: Loadings	12.3(7)	1.170(2)	.56	.999	0	.027	7515	7598
	3: Intercepts	13.6(9)	1.294(2)	.52	1	0	.020	7512	7587
	4: Residual variances	14.2(12)	0.196(3)	.98	1	0	.000	7507	7569
	5: Factor means	14.3(13)	0.102(1)	.75	1	0	.000	7505	7563
3	1: Configural	1.43(5)	–	–	1	–	.000	4836	4918
	2: Loadings	2.63(7)	1.31(2)	.520	1	0	.000	4834	4908
	3: Intercepts	4.74(9)	2.15(2)	.342	1	0	.000	4832	4898
	4: Residual variances	13.90(12)	6.37(3)	.095	1	0	.013	4835	4890
	5: Factor means	13.93(13)	0.03(1)	.857	1	0	.000	4833	4884

Notes. N = 535 in Dataset 1; N = 477 in Dataset 2; and N = 299 in Dataset 3.

Estimator = robust Maximum Likelihood (MLM)

D. = Dataset; HILS = Harmony in life scale, where 3 and 5 refer to the number of items.

Table 6. Test-retest reliability for the scales.

Dataset	Variables	r
1	SWLS-3 at T1 and T2	.83
	SWLS-5 at T1 and T2	.84
	HILS-3 at T1 and T2	.72
	HILS-5 at T1 and T2	.77
2	SWLS-3 at T1 and T2	.79
	SWLS-5 at T1 and T2	.82
	HILS-3 at T1 and T2	.70
	HILS-5 at T1 and T2	.71
3	SWLS-3 at T1 and T2	.81
	HILS-3 at T1 and T2	.74

Notes. For all correlations p < .001; N = 535 in Dataset 1; N = 477 in Dataset 2; and N = 299 in Dataset 3.

SWLS = Satisfaction with life scale; HILS = Harmony in life scale. The number after scales abbreviation refer to number of items.

Table 7. Results from Measurement Invariance Analyses of the SWLS Across Gender.

D.	Model	χ^2(df)	Δχ^2(df)	p	CFI	ΔCFI	RMSEA	AIC	BIC
1		SWLS-5
	1: Configural	32.4(10)	–		.992	–	.066	12945	13085
	2: Loadings	42.3(14)	9.35(4)	.052	.989	.003	.064	12947	13068
	3: Intercepts	48.5(18)	6.46(4)	.167	.988	.001	.060	12945	13048
	4: Residual variances	55.0(23)	4.10(5)	.535	.988	.001	.051	12942	13021
	5: Factor means	58.9(24)	3.78(1)	.051	.987	.001	.053	12944	13018
		SWLS-3
	1: Configural	0.00(0)	–	–	–	–	.000	7648	7732
	2: Loadings	4.40 (2)	3.55(2)	.169	.998	–	.049	7648	7723
	3: Intercepts	4.40 (4)	0.00(2)	1.00	1	.002	.000	7644	7710
	4: Residual variances	7.19 (7)	1.61(3)	.657	1	.000	.000	7641	7693
	5: Factor means	12.46(8)	5.15(1)	.023*	.999	.001	.024	7645	7691
2		SWLS-5
	1: Configural	31.3(10)	–		.996	–	.057	13386	13529
	2: Loadings	45.5(14)	14.65(4)	.005**	.994	.003	.064	13392	13516
	3: Intercepts	74.4(18)	31.80(4)	<.001***	.987	.006	.080	13413	13518
	4: Residual variances	82.7(23)	3.88(5)	.566	.988	.001	.069	13411	13492
	5: Factor means	83.2(24)	0.54(1)	.465	.988	.000	.067	13410	13486
		SWLS-3
	1: Configural	0.00(0)	–	–	–	–	.000	7980	8066
	2: Loadings	1.87 (2)	1.76(2)	.414	1	–	.000	7978	8054
	3: Intercepts	4.22 (4)	2.36(2)	.307	1	0	.008	7977	8043
	4: Residual variances	12.02 (7)	2.90(3)	.407	1	0	.000	7979	8031
	5: Factor means	12.04 (8)	0.02 (1)	.899	1	0	.000	7977	8024
		SWLS-3
3	1: Configural	0.00(0)	–	–	NA	–	0	3312	3381
	2: Loadings	0.67(2)	0.69(2)	.709	1	–	0	3308	3370
	3: Intercepts	1.24(4)	0.57(2)	.754	1	0	0	3305	3359
	4: Residual variances	9.61(7)	3.81(3)	.283	1	0	0	3307	3349
	5: Factor means	10.97(8)	1.39(1)	.239	1	0	0	3307	3345

Notes. N = 787 in Dataset 1; N = 860 in Dataset 2; and N = 342 in Dataset 3.

Estimator = robust Maximum Likelihood (MLM)

D. = Dataset; SWLS = Satisfaction with life scale, where 3 and 5 refer to the number of items.

Table 8. Results from measurement invariance analyses of the HILS across gender.

D.	Model	χ^2(df)	Δχ^2(df)	p	CFI	ΔCFI	RMSEA	AIC	BIC
1		HILS-5
	1: Configural	64.3(10)	–	–	.979	–	.109	11194	11334
	2: Loadings	71.7(14)	4.97(4)	.291	.979	.001	.093	11194	11315
	3: Intercepts	81.7(18)	10.81(4)	.029*	.976	.003	.088	11196	11298
	4: Residual variances	86.4(23)	2.05(5)	.842	.979	.003	.073	11190	11270
	5: Factor means	93.0(24)	6.31(1)	.012*	.976	.002	.075	11195	11270
		HILS-3
	1: Configural	0.00(0)	–	–	–	–	.000	6759	6843
	2: Loadings	4.37(2)	3.29(2)	.193	.999	–	.047	6759	6834
	3: Intercepts	9.82(4)	5.65(2)	.059	.997	.002	.058	6761	6826
	4: Residual variances	12.42(7)	1.02(3)	.797	1	.003	.007	6757	6809
	5: Factor means	19.95(8)	7.33(1)	.007**	.996	.004	.046	6763	6809
2		HILS-5
	1: Configural	63.4(10)	–	–	.990	–	.099	11718	11861
	2: Loadings	65.1(14)	1.2(4)	.877	.991	.001	.080	11712	11836
	3: Intercepts	66.8(18)	1.8(4)	.778	.992	.000	.068	11706	11810
	4: Residual variances	102.1(23)	9.4(5)	.094	.988	.004	.073	11731	11812
	5: Factor means	102.2(24)	0.0(1)	.865	.988	.000	.071	11729	11805
		HILS-3
	1: Configural	0.00(0)	–	–	–	–	.000	7034	7119
	2: Loadings	0.50(2)	0.42(2)	.811	1	–	.000	7030	7106
	3: Intercepts	1.39(4)	0.89(2)	.640	1	.000	.000	7027	7094
	4: Residual variances	23.51(7)	5.02(3)	.170	.998	.002	.044	7043	7095
	5: Factor means	23.55(8)	0.05(1)	.829	.998	.000	.038	7041	7089
		HILS-3
3	1: Configural	0.00(0)	–	–	1	–	0	2976	3045
	2: Loadings	0.11(2)	0.13(2)	.936	1	0	0	2972	3034
	3: Intercepts	0.94(4)	0.82(2)	.664	1	0	0	2969	3023
	4: Residual variances	5.81(7)	2.83(3)	.418	1	0	0	2968	3010
	5: Factor means	9.11(8)	3.52(1)	.060	1	0	0	2969	3008

Notes. N = 787 in Dataset 1; N = 860 in Dataset 2; and N = 342 in Dataset 3.

Estimator = robust Maximum Likelihood (MLM)

D. = Dataset; HILS = Harmony in life scale, where 3 and 5 refer to the number of items.

Table 9. Pearson’s r correlation comparisons between three- and five-item scales in dataset 1.

Variables	SWLS-3	SWLS-5	ΔrSWLS	HILS-3	HILS-5	ΔrHILS
Happiness (SHS)	.66***	.65***	.01	.69***	.72***	−.03
Psychological Well-Being (SPWB)	.40***	.39***	.01	.48***	.53***	−.05
Autonomy	−.05	−.03	−.02	.03	.05	−.02
Environmental mastery	.59***	.58***	.01	.64***	.69***	−.05
Personal growth	.10*	.08	.02	.17***	.20***	−.03
Positive relations with others	.29***	.28***	.01	.34***	.38***	−.04
Purpose in life	−.02	−.04	.02	.03	.05	−.02
Self-acceptance	.66***	.66***	.00	.68***	.72***	−.04
Depression (DASS-21)	−.28***	−.24***	−.04	−.34***	−.39***	.05
Anxiety (DASS-21)	−.03	−.01	−.02	−.11*	−.13**	.02
Stress (DASS-21)	−.14***	−.10*	−.04	−.23***	−.26***	.03
Social Desirability	.30***	.29***	.01	.33***	.35***	−.02

Notes. N = 535; ^*p < .05; ^**p < .01; ^***p < .001.

SWLS = Satisfaction with Life Scale; HILS = Harmony in Life Scale; SHS = Subjective Happiness Scale; SPWB = Scales of Psychological Well-Being; DASS-21 = Depression Anxiety and Stress Scales with 21 items; Social Desirability = Marlow-Crowne Social Desirability Scale-Form A.

Table 10. Pearson’s r correlation comparisons between three- and five-item scales in dataset 2.

Variables	SWLS-3	SWLS-5	ΔrSWLS	HILS-3	HILS-5	ΔrHILS
Depression (PHQ-9)	−.65***	−.64***	−.01	−.66***	−.67***	.01
Anxiety (GAD-7)	−.61***	−.60***	−.01	−.66***	−.67***	.01
Social Desirability	.16***	.19***	−.03	.18***	.19***	−.01

Notes. N = 477; ^***p < .001.

SWLS = Satisfaction with Life Scale; HILS = Harmony in Life Scale; PHQ-9 = Patient Health Qustionnaire-9; GAD-7 = Generalized Anxiety Disorder-7; Social Desirability = Marlow-Crowne Social Desirability Scale-Form A