1) Exploratory factor analysis about Collective efficacy scale
1-1) Each question’s mean, standard error and normal distribution The Mean, standard error, kurtosis, skewness value of each questions are in [Table 2].
[Table 2] Descriptive statistics about collective efficacy questions
Question Mean S.D Kurtosis Skewness
Q01 4.30 .583 -.582 -.160
Q02 4.34 .676 3.353 -1.156
Q03 3.96 .796 1.499 -.748
Q04 3.75 .762 .761 -.316
Q05 4.36 .700 1.432 -.995
Q06 4.12 .765 2.092 -.960
Q07 4.24 .738 1.234 -.897
Q08 4.04 .768 3.330 -1.190
Q09 4.12 .825 2.447 -1.169
Q10 4.14 .820 1.769 -1.006
Q11 4.07 .773 3.397 -1.230
Q12 4.00 .758 3.660 -1.277
Q13 4.14 .775 3.916 -1.390
Q14 4.04 .879 2.580 -1.265
Q15 3.91 .975 2.175 -1.333
Q16 3.72 1.126 .878 -1.173
Q17 3.99 1.012 2.272 -1.453
Q18 4.07 .768 4.485 -1.466
Q19 3.16 .989 .074 -.753
Q20 3.51 .932 1.665 -1.147
Q21 3.68 .971 2.383 -1.540
Q22 3.75 .951 3.116 -1.737
Q23 3.59 .945 1.918 -1.305
1-2) Exploratory factor analysis result
Results of exploratory factor analysis are as in [Table 3].
KMO(Kaiser-Meyer-Olkin Measure) value that verifies sample goodness on the whole material is between 0~1, however good when it's near to 1. KMO index appeared 0.869 in this research analysis result, and Bartlett's sphericity, that indicates goodness of the factor, is to test null hypothesis, correlation matrix is unit matrix, it could be determined that test value on 23 variables of this model is 2109.028 and level of significance is .000 level, accordingly, common factor proper for factor analysis can be said to exist. That is, variables can be said to have relationship without being independent.
As the factor analysis result, 5 major factors were classified.
Purpose of factor analysis is in reduction of material, i.e. reducing the number of variables. Therefore, number of factors should be comprehended based on a certain standard, of which standard becomes eigenvalues.
In this research, the factors with eigenvalues over 1 are 5, e.g.
Factor 1=6.48, Factor 2=2.87, Factor 3=1.59, Factor 4=1.38, and Factor 5=1.00, accordingly, factors of 23 questions that measure group efficacy could be divided into 5. Also, to see the explanation power of each factor displays Factor 1=28.21, Factor 2=12.47, Factor 3=6.92, Factor 4=6.01, Factor 5=4.35, on the whole 57.97. Which showed significant result. Eigenvalues of 5 factors appeared 1.00~6.48, and predictable variation appeared 4.35~28.21. Load value of Factor 1
appeared 0.50~0.81, Factor 2, 0.64~0.84, Factor 3, 0.48~0.71, Factor 4, 0.50~0.78, and Factor 5 displayed 0.44~0.80.
[Table 3] Exploratory factor analysis about collective efficacy questions
Question Factor1 Factor2 Factor3 Factor4 Factor5 h²
Q16 .817 -.051 .065 -.018 .059 .678
Q17 .762 .019 .062 .115 .077 .604
Q14 .632 .079 .254 .314 .033 .570
Q15 .620 .033 .165 .230 -.037 .467
Q18 .553 .194 .291 .367 .165 .591
Q13 .505 .139 .319 .445 .182 .607
Q23 .103 .840 -.052 .018 .033 .720
Q22 .024 .772 .138 .075 .002 .622
Q20 -.063 .770 -.013 .102 .004 .608
Q21 .060 .720 .047 -.017 -.085 .531
Q19 .045 .649 -.026 -.042 .100 .435
Q08 .220 .049 .710 -.033 .079 .562
Q02 -.010 .030 .705 .237 .127 .571
Q07 .344 -.072 .693 .129 -.098 .631
Q09 .256 .046 .558 .339 .100 .504
Q01 -.040 .024 .489 .463 .251 .519
Q05 .229 -.050 .104 .780 -.007 .675
Q10 .424 .063 .131 .559 .047 .516
Q06 .204 .031 .412 .509 -.058 .475
Q04 -.050 .028 -.109 .101 .809 .679
Q03 .146 -.131 .323 -.155 .718 .682
Q11 .342 .166 .176 .415 .452 .551
Q12 .344 .259 .312 .247 .441 .538
Eigen
value 6.488 2.870 1.593 1.382 1.002
Exp Var 28.210 12.478 6.925 6.010 4.355
CUM Var 28.210 40.688 47.613 53.624 59.979
Factor name
Community service
Education, Publicize
Belonging, Response
Rapidity,
Trust Reciprocity
2) Confirmatory factor analysis about Collective efficacy scale
2-1) Confirmatory factor analysis result
The final model fit verdict was done by RMR, GFI, AGFI, RMSEA, NFI, TLI, CFI value. RMR, RMSEA, CFI value was suitable for goodness of fit, but the rest values are not suitable [Table 4].
Final model of collective efficacy measuring standard related to infectious disease in confirmatory factorial analysis is as in [Figure 1,2].
Standardized factor loading appeared Community service 0.58~0.77, Education, Publicize 0.49~0.84, Belonging, Response 0.47~0.68, Rapidity, Trust 0.54~0.65, Reciprocity 0.24~0.76
Also the coefficient of correlation between each factors were 0.38 to 0.86, that Community service and Belonging, Response factors coefficient of correlation was the highest, 0.86 and Education, Publicize and Belonging, Response factors coefficient of correlation was the lowest, 0.38 [Table 6].
[Table 4] Confirmatory factor analysis model fit Absolute
fit index RMR (Root mean-square residual) .041
GFI (Goodness of fit index) .879
AGFI (Adjusted GFI) .848
RMSEA (Root mean squared error of approximation) .059 Incremental
fit index NFI (Normed fit index) .831
TLI (Tucher-Lewis index .899
CFI (Comparative fit index) .912
2-2) Convergent validity assessment
AVE(Average Dispersion Extract) was calculated, 0.56 in Community service area, 0.58 in Education, Publicize area, 0.48 in Belonging, Response area, 0.51 in Rapidity, Trust area, and 0.45 in Reciprocity area. Since almost all AVE values were over 0.5, accordingly, it is considered to have concentrative validity.
And construct reliability was calculated, 0.86 in Community service area, 0.87 in Education, Publicize area, 0.82 in Belonging, Response area, 0.75 in Rapidity, Trust area, and 0.73 in Reciprocity area. Since all construct reliability values were over 0.7, it is considered to have concentrative validity [Table 5].
[Fig 1] Measurement Model for CFA (Standardized estimates)
[Fig 2] Measurement Model for CFA (Unstandardized estimates)
[Table 5] Convergent validity assessment result
Estimate S.E. C.R P Standardized
coefficients AVE Construct Reliability Community service → Q13 .823 .081 10.172 *** .771
0.561 0.864 Community service → Q14 .856 .090 9.497 *** .707
Community service → Q15 .790 .097 8.147 *** .588
Community service → Q16 1.00 - - - .645
Community service → Q17 .980 .104 9.463 *** .703 Community service → Q18 .805 .080 10.076 *** .762 Education, Publicize → Q19 .618 .079 7.794 *** .491
0.582 0.871 Education, Publicize → Q20 .942 .067 14.049 *** .794
Education, Publicize → Q21 .920 .071 12.908 *** .745 Education, Publicize → Q22 1.01 .067 15.058 *** .837
Education, Publicize → Q23 1.00 - - - .831
Belonging, Response → Q01 .769 .112 6.882 *** .549
0.482 0.821 Belonging, Response → Q02 .766 .125 6.130 *** .471
Belonging, Response → Q07 1.00 - - - .564
Belonging, Response → Q08 1.02 .148 6.915 *** .553 Belonging, Response → Q09 1.35 .170 7.956 *** .680 Rapidity, Trust → Q05 .707 .103 6.832 *** .539
0.511 0.757 Rapidity, Trust → Q06 .918 .118 7.786 *** .641
Rapidity, Trust → Q10 1.00 - - - .651
Reciprocity → Q03 .544 .097 5.595 *** .393
0.450 0.736
Reciprocity → Q04 .321 .093 3.444 *** .241
Reciprocity → Q11 .977 .097 10.073 *** .725
Reciprocity → Q12 1.00 - - - .757
2-3) Discriminant assessment
- χ2 difference between non-restrictive model & Restrictive model The result of analysing non-restrictive model that was applied with no restriction between Rapidity, Trust and Belonging, Response was χ
2=413.4 and the analysis result of restrictive model fixed with covariance by 1 between Rapidity, Trust and Belonging, Response was χ2=529.3.
When comparing χ2 of non-restrictive model and restrictive model, meaningful difference appears between two models as △χ2=115.9 when df=1, accordingly, discriminant validity is considered to exist.
(Generally, χ2 is compared to verify difference between non-restrictive model and restrictive model. When degree of freedom differs by 1, when difference of χ2 is over 3.84, statistically significant)
- Weather the result of equation [∅±2×S.E.] include 1 or not
This method is to use of correlation coefficient and standard error.
In case of assessment of discriminant validity, it was difficult to verify between all the variables, for the following reason, conceptually similar or selecting the highest pair of the correlation between the variables.
The reason why selecting the most high correlation between pairs of variables was that if the correlation is high, the discriminant validity would low.
The correlation coefficient between ‘Belonging, Response’ and
‘Rapidity, Trust’ was 0.87 [Table 6]. And the standard error between
[Table 6] Correlations between factors
Community
service
Education, Publicize
Belonging, Response
Rapidity,
Trust Reciprocity AVE Construct Reliability Community
service 1 0.561 0.864
Education,
Publicize .612 1 0.582 0.871
Belonging,
Response .859 .381 1 0.482 0.821
Rapidity,
Trust .758 .455 .875 1 0.511 0.757
Reciprocity .776 .576 .818 .627 1 0.450 0.736
[Table 7] Covariance between latent variables
Estimate S.E. C.R P
Community service ↔ Education, Publicize .348 .055 6.273 ***
Community service ↔ Belonging, Response .259 .042 6.100 ***
Community service ↔ Rapidity, Trust .293 .048 6.080 ***
Community service ↔ Reciprocity .322 .048 6.654 -
Education, Publicize ↔ Belonging, Response .124 .030 4.169 ***
Education, Publicize ↔ Rapidity, Trust .190 .040 4.760 ***
Education, Publicize ↔ Reciprocity .259 .042 6.137 ***
Belonging, Response ↔ Rapidity, Trust .193 .033 5.931 ***
Belonging, Response ↔ Reciprocity .195 .031 6.197 ***
Rapidity, Trust ↔ Reciprocity .191 .035 5.539 ***
two latent variables was 0.03 [Table 7]. Assign these figure as [∅
±2×S.E.], the result was [0.875±2×0.03=0.93~0.84]. It was not include 1, so discriminant validity was considered to exist.
3) Logistic regression
In accordance with the collective efficacy level and infectious disease knowledge was no statistically signifiant differences in the odds ratios.
But there was positive association between collective efficacy and infectious disease preventive behavior. When the collective efficacy level 1, the odds ratio was 4.64, CI 2.03-10.49, and level 2, the odds ratio was 3.45, CI 1.60-7.44, and level 3 the odds ratio was 4.70, CI 1.79-12.31. [Table 8,9,10]
[Table 8] The frequency between infectious disease knowledge, preventive behavior and collective efficacy
Knowledge (High) Behavior (High)
N % P-value N % P-value
Collective efficacy 0 75 25 33.33
0.6114
28 37.33
0.003
Collective efficacy 1 57 17 29.82 38 66.67
Collective efficacy 2 86 29 33.72 48 55.81
Collective efficacy 3 32 14 43.75 21 65.63
Gender
Men 122 46 37.70
0.227 56 45.90
0.012
Women 128 39 30.47 79 61.72
Age
20-34 51 13 25.49
0.020
22 43.14
0.141
34-49 69 19 27.54 34 49.28
50-64 91 32 35.16 55 60.44
≧65 39 21 53.85 24 61.54
Education
≦Middle school 55 31 56.36
0.000
35 63.64
0.237
High School 102 25 24.51 54 52.94
≧University 93 29 31.18 46 49.46 Occupation
Manual 105 38 36.19
0.002
54 51.43
0.564
Non-manual 36 20 55.56 18 50.00
Etc. 109 27 24.77 63 57.80
Region
Seoul 100 27 27.00
0.056 57 57.00
0.437
Chung-Nam 150 58 38.67 78 52.00
[Table 9] Infectious disease knowledge according to Collective efficacy level
Level of the infectious disease knowledge (Low/High)
Crude
OR 95% CI P-value Adjusted
OR 95% CI P-value
Collective efficacy 0 REF - - REF - -
Collective efficacy 1 0.85 0.40 1.79 0.668 0.56 0.23 1.31 0.181 Collective efficacy 2 1.10 0.53 1.96 0.958 0.63 0.28 1.39 0.258 Collective efficacy 3 1.55 0.67 3.63 0.306 1.42 0.55 3.63 0.458 Gender
Men REF - - REF - -
Women 0.72 0.43 1.22 0.228 0.93 0.48 1.80 0.849
Age
20-34 REF - - REF - -
34-49 1.11 0.48 2.52 0.800 0.82 0.34 1.98 0.663
50-64 1.58 0.73 3.39 0.236 1.07 0.45 2.54 0.864
≧65 3.40 1.39 8.30 0.006 1.76 0.58 5.35 0.318
Education
≦Middle school REF - - REF - - High School 0.25 0.12 0.50 0.000 0.31 0.13 0.74 0.008
≧University 0.35 0.17 0.70 0.002 0.36 0.12 1.09 0.072 Occupation
Manual 1.72 0.95 3.10 0.070 2.42 1.13 5.16 0.022
Non-manual 3.79 1.72 8.35 0.000 2.30 0.85 6.21 0.097
Etc. REF - - REF - -
Region
Seoul 0.58 0.33 1.01 0.057 0.73 0.36 1.48 0.393
Chung-Nam REF - - REF - -
* Adjusted with gender, age, education, occupation, region
[Table 10] Infectious disease preventive behavior according to Collective efficacy level Level of the infectious disease preventive behavior (Low/High)
Crude
OR 95% CI P-value Adjusted
OR 95% CI P-value
Collective efficacy 0 REF - - REF - -
Collective efficacy 1 3.35 1.63 6.91 0.001 4.64 2.03 10.49 0.000 Collective efficacy 2 2.12 1.12 3.99 0.019 3.45 1.60 7.44 0.001 Collective efficacy 3 3.20 1.34 7.62 0.008 4.70 1.79 12.31 0.001 Gender
Men REF - - REF - -
Women 1.90 1.14 3.14 0.012 1.70 0.91 3.15 0.091
Age
20-34 REF - - REF - -
34-49 1.28 0.61 2.65 0.505 1.30 0.58 2.91 0.522
50-64 2.01 1.00 4.03 0.048 1.73 0.78 3.84 0.173
≧65 2.10 0.90 4.93 0.085 1.71 0.58 5.02 0.326
Education
≦Middle school REF - - REF - - High School 0.64 0.32 1.26 0.198 0.57 0.24 1.35 0.203 Over university 0.55 0.28 1.10 0.095 0.45 0.15 1.32 0.149 Occupation
Manual 0.77 0.45 1.32 0.349 1.29 0.64 2.60 0.475
Non-manual 0.73 0.34 1.55 0.414 0.67 0.25 1.79 0.434
Etc. REF - - REF - -
Region
Seoul 1.22 0.73 2.03 0.437 2.65 1.33 5.27 0.005
Chung-Nam REF - - REF - -
* Adjusted with gender, age, education, occupation, region
[Table 11] Cronbach’s α coefficient
Factor Questions number Cronbach's alpha Standardization Community service Q13, Q14, Q15, Q16, Q17, Q18 6 0.83 0.83 Education, Publicize Q19, Q20, Q21, Q22, Q23 5 0.80 0.81
Belonging, ResponseQ1, Q2, Q7, Q8, Q9 5 0.74 0.75
Rapidity, Trust Q5, Q6, Q10 3 0.65 0.66
Reciprocity Q3, Q4, Q11, Q12 4 0.64 0.65
Total 0.85 0.86
3.5.2 Reliability assessment
Internal consistency was determined with Cronbach’s α. The internal consistency reliability (Cronbach’s α coefficient) ranged from 0.64 to 0.83 for all scales show the Cronbach’s α coefficient of the collective efficacy question [Table 11].