Evaluating organizational stress-management interventions using ...

EVALUATION OF INTERVENTIONS 31
F(1, 36) = 1.27, p 4 .05. When triangulated with other methods of process
evaluation this finding appeared robust. Stakeholder analysis indicated that
some senior managers had resisted informing staff of the intervention
because of the budgetary constraints placed on particular groups of stations.
This was supported by two other pieces of data: (1) There was no evidence
of the intervention in communication records for some stations, and (2)
those who were unaware of the intervention shared the same communication
routes.
Evaluation of the intervention. Using the traditional nonadaptive pre –
post study design, there was no significant change in exhaustion scores,
t = 0.64, p 4 .05; F(1, 36) = 0.24, p 4 .05, over the intervention period (see
TABLE 1
Changes in exhaustion score (Study 1, whole sample)
Preintervention
(Time 1)
Postintervention
(Time 2)
Mean
change t F
Exhaustion score 20.3 (SD = 8.7) 18.9 (SD = 9.4) – 1.4 0.64* 0.24*
N = 37.
*p 4 .05.
TABLE 2
Repeated measures analysis of covariance (Study 1)
Type III sum of squares 1
F
Within-subjects effects
Time (pre – post intervention) 67.26 2.22
Time 6 Length of service 49.03 1.62
Time 6 Age 97.99 3.24
Time 6 Exposure to intervention 206.79 6.83**
Between-subjects effects
Age 566.21 6.13*
Length of service 1.79 0.02
Awareness of the intervention 352.47 3.82
N = 37.
*p 5 .05; **p 4 .01.
1 Used here to take into account the discrepancy in sample size between the group exposed to
the intervention and the group not exposed to the intervention.
Box’s M statistic was nonsignificant, F(3, 10402) = 0.68, p 4 .05, and Levene’s test of the
equality of error variance was nonsignificant: for preintervention exhaustion scores,
F(1, 35) = 0.19, p 4 .05; for postintervention exhaustion scores, F(1, 35) = 0.05, p 4 .05.