Descriptive statistics of the sample
After three months of recruitment, a sample size of N = 62 completed questionnaires was reached. However, we had to exclude 16 participants from data analysis due to unmet inclusion criteria, resulting in a final sample size of N = 46. All participants were German citizens. Most of the participants work in the IT industry (N = 40 or 86.9%), in large enterprises (N = 25 or 54.3%). However, although this result may be biased by recruitment strategy, distribution of industry and enterprise size confirms previous findings among virtual teams (RW³ Culture Wizard, 2018). Further results are provided in Table 2.
Table 2 Sociodemographic and Occupational Characteristics of the Sample (N = 46)
Variable
|
n
|
%
|
Gender
|
|
|
Female
|
11
|
23.9
|
Male
|
35
|
76.1
|
Age
|
|
|
18-20 years
|
1
|
2.2
|
21-30 years
|
10
|
21.7
|
31-40 years
|
18
|
39.1
|
41-50 years
|
7
|
15.2
|
51-60 years
|
9
|
19.6
|
61-70 years
|
1
|
2.2
|
Highest educational level
|
|
|
Secondary education
|
9
|
19.6
|
Higher education
|
37
|
80.4
|
Managerial responsibility
|
|
|
Yes
|
20
|
43.5
|
No
|
26
|
56.5
|
Work experience
|
|
|
1-2 years
|
13
|
28.3
|
3-5 years
|
16
|
43.8
|
6-10 years
|
7
|
15.2
|
≥ 11 years
|
10
|
21.7
|
Average working hours per week
|
|
|
35-40 hours
|
18
|
39.1
|
41-45 hours
|
18
|
39.1
|
≥ 46 hours
|
10
|
21.7
|
Descriptive statistics of the main variables
54.3% of all participants reported that their employers provided personnel development or health promotion offers, but only 39.1% of those who were offered this opportunity made use of it. Means, standard deviations, Cronbach’s α, and zero-order correlations of the main variables are provided in Table 3.
Table 3 Means, Standard Deviations, Internal Consistencies, and Zero-Order Correlations
Variable
|
M
|
SD
|
Range
|
Min
|
Max
|
1
|
2
|
3
|
4
|
5
|
1. Boundarylessness
|
2.870
|
.966
|
1-5
|
1.000
|
5.000
|
(.866)
|
|
|
|
|
2. Virtuality
|
3.541
|
.524
|
1-5
|
2.625
|
4.875
|
.092
|
(.561)
|
|
|
|
3. Psychological detachment
|
3.011
|
.823
|
1-5
|
1.000
|
4.500
|
.351**
|
.237
|
(.844)
|
|
|
4. Perceived stress
|
2.490
|
.559
|
1-5
|
1.700
|
3.800
|
-.359**
|
-.241
|
-.215
|
(.843)
|
|
5. Sleep quality
|
3.766
|
.706
|
1-5
|
2.000
|
5.000
|
.018
|
-.367**
|
-.279*
|
.282*
|
(.815)
|
Note. N = 46. One-tailed Spearman Correlation Coefficients were used. * p < .05. * p < .01. Cronbach’s alphas are listed in parentheses on the diagonal.
Descriptive statistics of virtual job demands and health promotion offers
We also evaluated job demands other than boundarylessness using another self-developed scale as well as free text answers. Six participants reported specific job demands, such as a need for clear and measurable objectives, lack of social exchange, availability and high discipline, as well as different levels of media skills and technological equipment among virtual team members. Results from the descriptive analysis of the virtual job demands scale are provided in Table 4.
Table 4 Descriptive Statistics for Virtual Job Demands
Item
|
M
|
SD
|
Min
|
Max
|
Team members in different time zones
|
1.739
|
1.255
|
1
|
5
|
Team members with other mother tongues or dialects
|
2.848
|
1.414
|
1
|
5
|
Team members with different cultural backgrounds
|
2.935
|
1.357
|
1
|
5
|
Higher susceptibility to errors in communication
|
2.457
|
1.609
|
1
|
5
|
Higher susceptibility to conflicts among virtual team members
|
2.391
|
1.105
|
1
|
5
|
More difficulties due to diverse cultural and linguistic backgrounds
|
1.935
|
.952
|
1
|
5
|
More difficulties due to geographical distance
|
2.196
|
1.046
|
1
|
5
|
Restricted possibility of social exchange
|
3.130
|
1.128
|
1
|
5
|
More difficulties of socially integrating virtual team members
|
3.087
|
1.226
|
1
|
5
|
More difficulties in performance assessment
|
2.500
|
1.169
|
1
|
5
|
Difficulties to build trust in virtual team members
|
2.304
|
1.133
|
1
|
5
|
Satisfaction with communication within virtual team
|
4.087
|
.812
|
2
|
5
|
Satisfaction with collaboration within virtual team
|
4.152
|
.868
|
1
|
5
|
Note. N = 46. All scales are five-point Likert scales, ranging from one to five.
Relationships between boundarylessness, virtuality, psychological detachment, and health outcomes
Results from multiple regression analyses are provided in Table 5 and Table 6.
Table 5 Regression Analysis on Sleep Quality
Variable
|
Model 1a
|
Model 2b
|
Model 3c
|
Model 4d
|
Model 5e
|
B
|
SE
|
β
|
B
|
SE
|
β
|
B
|
SE
|
β
|
B
|
SE
|
β
|
B
|
SE
|
β
|
Constant
|
.000
|
.105
|
|
.000
|
.095
|
|
.000
|
.102
|
|
-.009
|
.105
|
|
-.038
|
.109
|
|
Boundary-lessness
|
-.017
|
.087
|
-.023
|
|
|
|
-.001
|
.094
|
-.002
|
-.005
|
.098
|
-.007
|
-.006
|
.103
|
-.008
|
Perceived Stress
|
|
|
|
-.455*
|
.174*
|
-.360*
|
-.455*
|
-.180*
|
-.360*
|
-.456*
|
.185*
|
-.361*
|
-.458*
|
.193*
|
-.363*
|
B x Vf
|
|
|
|
|
|
|
|
|
|
.056
|
.192
|
.036
|
.018
|
.203
|
.012
|
B x PDg
|
|
|
|
|
|
|
|
|
|
|
|
|
-.107
|
.110
|
-.123
|
R2
|
.001
|
.130*
|
.130
|
.131
|
.146
|
Adjusted R2
|
-.022
|
.110*
|
.089
|
.069
|
.062
|
R2-Change
|
.001
|
.130
|
.129
|
.001
|
.015
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Note. N = 46. All variables were centred at their means for moderation analysis. Regression coefficients and standard errors based on 1000 bootstrap samples. * p < .05.
a Model 1 tests Hypothesis H1. b Model 2 tests Hypothesis H2b (tested separately). c Model 3 tests Hypothesis H2c. d Model 4 tests Hypothesis H3c. e Model 5 tests Hypothesis H4c. f B x V abbreviates the interaction of boundarylessness and virtuality. g B x PD abbreviates the interaction of boundarylessness and psychological detachment.
Table 6 Regression Analysis on Perceived Stress
Variable
|
Model 6a
|
Model 7b
|
Model 8c
|
Model 9d
|
Model 10e
|
B
|
SE
|
β
|
B
|
SE
|
β
|
B
|
SE
|
β
|
B
|
SE
|
β
|
B
|
SE
|
β
|
Constant
|
.000
|
.083
|
|
.000
|
.083
|
|
-.015
|
.100
|
|
-.018
|
.098
|
|
-.016
|
.106
|
|
Boundarylessness
|
.034
|
.098
|
.059
|
-.005
|
.113
|
-.009
|
-.014
|
.124
|
-.024
|
-.072
|
.141
|
-.125
|
-.072
|
.150
|
-.125
|
Virtuality
|
|
|
|
.212
|
.168
|
.199
|
.228
|
.185
|
.214
|
.215
|
.189
|
.201
|
.215
|
.191
|
.201
|
B x Vf
|
|
|
|
|
|
|
.086
|
.216
|
.071
|
.104
|
.232
|
.086
|
.106
|
.237
|
.087
|
Psychological Detachment
|
|
|
|
|
|
|
|
|
|
-.164
|
.112
|
-.241
|
-.164
|
.121
|
-.242
|
B x PDg
|
|
|
|
|
|
|
|
|
|
|
|
|
.005
|
.171
|
.007
|
R2
|
.004
|
.038
|
.043
|
.090
|
.090
|
Adjusted R2
|
-.019
|
-.006
|
-.025
|
.002
|
-.023
|
R2-Change
|
.004
|
.035
|
.005
|
.047
|
.000
|
Note. N = 46. All variables were centred at their means for moderation analysis. Regression coefficients and standard errors based on 1000 bootstrap samples.
a Model 6 tests Hypothesis H2a. b Model 7 tests Hypothesis H3a. c Model 8 tests Hypothesis H3b. d Model 9 tests Hypothesis H4a. eModel 10 tests Hypothesis H4b. f B x V abbreviates the interaction of boundarylessness and virtuality. g B x PD abbreviates the interaction of boundarylessness and psychological detachment.
As can be seen from these tables, significant associations between independent variables and sleep quality as an outcome were found, whereas relationships with perceived stress did not reach significance. Testing for Hypothesis H1 showed no significant negative relationship between boundarylessness and sleep quality (F(1,44) = .023, p=.880, R2=.001). Likewise, Hypothesis H2a, a positive relationship between boundarylessness and perceived stress, could not be confirmed (F(1, 44) = .155, p = .695, R2 = .004). On the contrary, Hypothesis H2b reached significance, confirming a negative association of perceived stress with sleep quality (F(1, 44) = 6.564, p = .014, R2 = .130). Testing Hypothesis H2c did not reveal the predicted significant mediation effect of perceived stress on the relationship between boundarylessness and sleep quality, as results from entering the predictors into the regression model (F(1, 43) = 3.208, p = .050, R2 = .130) as well as a subsequent Sobel test (z =-.344, SE = .045, p = .731) show. Moreover, testing Hypotheses H3a (F(1, 43) = .856, p = .432, R2 = .038), H3b (F(1, 42) = .630, p = .600, R2 = .043), and H3c (F(1, 42) = 2.112, p = .113, R2 = .131) could neither confirm virtuality as a predictor of perceived stress nor as a moderator. Similarly, Hypotheses H4a (F(1, 41) = 1.017, p = .410, R2 = .090), H4b (F(1, 40) = .794, p = .560, R2 = 0.090), and H4c (F(1, 41) = 1.748, p = .158, R2 = .146) could not be confirmed. Psychological detachment was not found to be a significant predictor of perceived stress or a moderator in our hypothesised model.
To shed more light on the health and working situation among virtual team members, we conducted another regression analysis to examine the direct relationship between virtuality and sleep quality as well as between psychological detachment and sleep quality. Both relationships were found significant: virtuality was negatively related to sleep quality (F(1, 44) = 4.131, p = .048, R2 = .086) and psychological detachment was associated positively with sleep quality (F(1, 44) = 5.018, p = .030, R2 = .102). Both standardised coefficients indicated medium effects (β = -.239 for virtuality and β = .320 for psychological detachment).
Differences in degrees of virtuality
In addition, we conducted median-split t-tests to examine differences between groups among the sample. Splitting the data into higher and lower degrees of virtuality revealed that those 50% of participants who reported a higher degree of virtuality in their teamwork also reported significantly higher values (t(44) = -2.327, p = .025, d = .685) of boundarylessness (M = 3.200, SD = .966, n = 22) than those who worked in a lower degree of virtuality team (M = 2.567, SD = .880, n = 24).
Differences in levels of boundarylessness
Moreover, splitting the data into higher and lower levels of perceived boundarylessness resulted in a significance difference with regard to psychological detachment (t(44) = 1.138, p = .003, d = .928). Participants who experienced lower levels of boundarylessness also reported higher levels of psychological detachment (M = 3.330, SD = .742, n = 24) compared to participants who experienced higher boundarylessness also reporting lower psychological detachment (M = 2.631, SD = .764, n = 22).
Differences in levels of psychological detachment
We also found differences in the levels of psychological detachment between participants with managerial responsibility and those without t(44) = 2.071, p = .044, d = .620). Compared to participants without managerial responsibility (M = 2.798, SD = .815, n = 26), managers reported higher levels of psychological detachment (M = 3.288, SD = .766, n = 20). All results from median-split t-tests are provided in Figure 2.