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the effect of daily hassles on salivary cortisol levels, it was observed that cortisol


levels were not significantly related to hassles earlier in time, even those reported to


have occurred within 2 h of the cortisol measurement; however, cortisol was signif-


icantly elevated during current or anticipated hassles (Smyth et al. 1998 ). In studies on


occupational groups in Hawaii (school teachers and hotel workers), Brown and col-


leagues found low, or even negative, correlations between biological markers of stress


and self-reports, as shown in Tables7.1and7.2(Brown unpublished data). The


biological markers consisted of urinary levels of epinephrine and norepinephrine


measured during work hours, and the variance in ambulatory blood pressure values


(systolic and diastolic blood pressure, respectively) taken at 20 min intervals during


work hours, while the self-reports consisted of the“psychological demand”portion of


the job content questionnaire (Karasek and Theorell 1990 ), and the score on a life


satisfaction survey which records a person’s desire to make changes in their life


(James et al. 1987 ).Therewerenosignificant correlations between the ambulatory


blood pressure and urinary catecholamine measures. Among the school teachers, there


were significant correlations between job content questionnaire scores and the life


satisfaction survey, as well as between ambulatory blood pressure variability and


scores on the job content questionnaire.


For the same two studies in Hawaii, there were much stronger relations between


the ambulatory blood pressure readings and diary reports of negative moods
(anxiety, anger, or sadness). In the study of hotel workers, both systolic and


diastolic blood pressure were significantly elevated at times when people reported


negative moods in their diaries; e.g., at work, an individuals’Z-scores of systolic


(two tailedttest,t= 6.2,p< .001) and diastolic BP (t= 3.7,p< .001) were sig-


nificantly higher at times when a negative mood was reported (Brown unpublished


data). Similar results were found in the school teacher study; e.g., at work,Z-scores


for systolic (t= 4.9,p< .001) and diastolic (t= 4.0,p< .001) blood pressure were


elevated at times of negative mood reports (Brown et al. 2003 ).


The poor correlation among many stress measures is due in part to the complex


nature of stress, and the time course of the responses being measured. Table7.3


shows an approximate time line for stress measures including time to response as


well as whether the response is stable or variable over the time course of extended


exposure to stress. The table makes clear why correlations between stress measures


are often quite low: the measures are evaluating conditions at different times or


durations during aprocessof response to a stress. The biological response to stress


changes over time, with different aspects of the response changing in different ways.


In simple terms, a major difference is in whether one is measuring an acute stress


response—and thus the alarm reaction, or a chronic stress response—and therefore


the stage of resistance in Selye’s model. This also brings the problem of under-


standing just what the experience of stress means. If someone exhibits a biological


response indicative of stress but does not report feeling stressed, is she actually


experiencing stress? If someone reports feeling stressed but does not exhibit a


biological stress response, is she under stress? There are no simple answers to these


questions, which need to be addressed within the specific circumstances of a given
study.


124 D.E. Brown

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