3.2 Measuring stress

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3.2 Measuring stress
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Learning outcomes

• Understand these three studies related to
  measuring stress
• Physiological measures (Geer, J. and Maisel, E.
  (1972) Evaluating the effects of the
  prediction-control confound, Journal of
  Personality and Social Psychology 23 (3),
  31419)
• Self-report (Holmes, T. H. and Rahe, R. H. (1967)
  The social readjustment rating scale, Journal
  of Psychosomatic Research 11, 1318)
• Combined approach (Johansson et al. (1978)
  Social psychological and neuroendocrine stress
  reactions in highly mechanised work, Ergonomics
  21 (8), 58399).

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Physiological measures Key study Geer and
Maisel (1972)

• Aim
• To see if perceived control or actual control can
  reduce stress reactions to aversive stimuli
  (photos of crash victims).
• Method
• Laboratory experiment.

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Participants

• 60 psychology undergraduates from New York
  University.
• Design
• Independent design as participants were randomly
  assigned to one of three conditions.

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Procedure

• Each participant was seated in a sound-shielded
  room and wired up to galvanic skin response (GSR)
  and heart-rate monitors.
• Group 1 were given actual control over how long
  they saw each photograph for.
• Group 2 were yoked to the actual control group,
  warned how long the photos would be shown for and
  that a noise would precede them.
• Group 3 were also yoked to actual control group,
  but were told that that from time to time they
  would see photographs and hear tones.

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Procedure (cont.)

• A Beckman Model RB polygraph was used to collect
  psycho-physiological data.
• The data was converted from a voltmeter to a
  printout.
• Each recording was performed in a sound and
  electrically-shielded room to ensure no audio or
  visual input from the projector would interfere
  with the data collection.

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Procedure (cont. 2)

• The heart monitors were attached in standard
  positions, and the GSR electrodes were placed
  between the palm and forearm of the participants
  non-preferred arm e.g. left arm for right-handed
  people.

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Findings

• The predictability group (Group 2) were most
  stressed by the tone as they knew what was
  coming, but did not have control over the
  photograph.
• The control group (Group 1) were less stressed by
  the photograph than the predictability group and
  no-control group (Groups 1 and 2) as they had
  control.

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Conclusions

• It is likely that having the control to terminate
  aversive stimuli reduces the stressful impact of
  those stimuli.

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Self reportKey study Holmes and Rahe (1967)

• Aim
• Creating a method that estimates the extent to
  which life events are stressors.

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Method

• A questionnaire designed to ascertain how much
  each life event was considered a stressor.
• Participants
• 394 subjects.

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Procedure

• Each participant was asked to rate a series of 43
  life events.
• Marriage was given an arbitrary rating of 500 and
  each event was to be judged as requiring more or
  less readjustment.
• It could be based on personal experience and
  perceptions of other people.
• The final Social Readjustment Rating Scale was
  completed based on the mean scores.

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Findings

• Correlations between groups were tested and found
  to be high in all but one group.
• Males and females agreed.
• Participants of different ages, religions,
  educational level agreed.
• There was less correlation between white and
  black participants.

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Conclusions

• The degree of similarity between different groups
  is impressive and shows agreement in general
  about what constitutes life events and how much
  they cause stress (or readjustment).

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Combined approach Key study Johansson et al.
(1978)

• Aim
• To measure the psychological and physiological
  stress response in two categories of employees.
• Method
• A quasi-experiment where workers were defined as
  being at high risk (of stress) or in a control
  group.

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Participants

• 24 workers at a Swedish sawmill.
• The high-risk group was 14 workers who had to
  work at a set pace. Their job was complex and
  they were responsible for their own and their
  teams wages.
• The control group was 10 workers who were
  cleaners, or maintenance men.

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Design

• An independent design with participants already
  working in one of the two categories, so no
  manipulation of the independent variable.

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Procedure

• Each participant was asked to give a daily urine
  sample when they arrived at work and at four
  other times during the day. They also gave
  self-reports of mood and alertness plus caffeine
  and nicotine consumption.
• The baseline measurements were taken at the same
  time on a day when the workers were at home.

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Procedure (cont.)

• Each participant gave a urine sample four times
  during the day, so that their adrenaline levels
  could be measured. Their body temperature was
  also measured at the same time. These
  physiological measurements gave an indication of
  how alert the participants were.
• Self-rating scales of words such as sleepiness,
  wellbeing, irritation and efficiency were
  made on scales from none to maximal (the highest
  level the person had ever experienced).
• Caffeine and nicotine consumption were noted.

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Findings

• The high-risk group had adrenaline levels twice
  as high as their baseline and these continued to
  increase throughout the day. The control group
  had a peak level of 1 ½ times baseline level in
  the morning and this then declined during the
  rest of their shift.
• In the self-report, the high-risk group felt more
  rushed and irritated than the control group. They
  also rated their wellbeing lower than the control
  group.

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Conclusions

• The repetitive, machine-paced work, which was
  demanding in attention to detail and was highly
  mechanised, contributed to the higher stress
  levels in the high-risk group.