Measuring Stress

 

Sarafino pages 91 to 97

Physiological arousal

One way to assess arousal is to use electrical/mechanical equipment to take measurements of blood pressure, heart rate, respiration rate, or galvanic skin response (G. S. R.). The Polygraph measures all of these simultaneously. Miniature Polygraphs can be carried around. Researchers using a miniature Polygraph were able to find that ambulance workers had higher blood pressure whilst at work compared with when they were at home (Goldstein et al. 1992).

Blood or urine samples can be assessed for the level of hormones that the adrenal glands secrete. There are two main classes of hormones: corticosteroids (for example cortisol) and catecholamines (for example, adrenaline and noradrenaline. Measurements need to be analysed by a chemist using special procedures and equipment.

There are several advantages to using measures of physiological arousal to assess stress. Physiological measures are reasonably direct and objective, quite reliable, and easily quantified. The disadvantages are that the techniques are expensive, the technique is stressful for some people and the measures are affected by factors such as gender, weight, activity prior to measurement and such substances as caffeine.

Life events

Holmes and Rahe (1967)
Test your stress using Holmes and Rahe(1967)

The most widely used scale of life events has been the 'social readjustment rating scale (SRRS.)' developed by Holmes and Rahe (1967). The scale was made by constructing a list of events that were derived from clinical experience. Hundreds of men and women of various ages and backgrounds rated the amount of readjustment needed by people experiencing each of the stressful events. They were asked to give the average degree of readjustment.

To measure the amount of stress people have experienced subjects check off each life event they have experienced during the past 24 months. The values of the check items are then totalled to give the stress score.

A survey of nearly two thousand eight hundred adults who filled in a version of the SRRS found that 15% experienced none of the events during the prior year, and 18% reported five or more. The three most frequent events were "took a vacation" (43%), "the death of a loved one or other important person" (22%), and "illness or injury" (21%). The older the person the fewer life events reported and the more educated the person more life events were reported. Single, separated, and divorced people reported a larger number of events compared with married and widowed individuals (Goldberg & Comstock, 1980).

Strengths and weaknesses of the SRRS.

 

Problems with the scale

  1. Major life events are rare therefore low scores
  2. Some items are ambiguous. Items in the SRRS are vague or ambiguous (Hough et al, 1976). For example, "change in responsibilities at work" does not take into account how much change or whether there is more or less responsibility. "personal injury or illness" does not take into account the seriousness of the illness. This reduces the precision of the instrument.
  3. Value of items vary depending on what group the respondent belongs to.
  4. Large individual differences in ability to cope
  5. large cultural differences in our experience of events.
  6. Value of events change over time. So text loses its validity.
  7. A weakness of the SRRS is that there is a poor correlation (about .30) between the score and illness (Dohrenwend & Dohrenwend, 1981). One reason could be that there are other many possible reasons for why people get sick and have accidents.
  8. The scale does not consider the meaning or impact of an event for the individual (Cohen et al, 1983). For example, two people who each had a mortgage for 20,000 dollars would get the same score for "mortgage over 10,000 dollars" even though one of them made ten times the income of the other. The amount of stress caused by the "death of spouse" could depend upon the age, dependence on the spouse, and the length and happiness of the marriage. This again reduces the precision of the instrument.
  9. The scale does not distinguish between desirable and undesirable events. "Marriage" or "outstanding personal achievement" are often viewed as desirable; but "sex difficulties" and "jail term" are obviously seen as undesirable. Some items can be viewed either way, for example, "change in financial state"; the score is the same regardless of whether the finances improve or worsen. Studies have found that undesirable life events are correlated with illness, but desirable events are not (McFarlane et al, 1983).

High correlation between men and women, Catholics and Protestants. Not so high for Black Vs White.

The SRRS has face validity because many of the events listed are easily recognisable as stressful events. The values Al located to each stress event have been carefully calculated from data provided by the opinions of many people. The survey form can be filled out easily and quickly.

Other life events scales

The life experiences survey (LES)

This is an improvement. It consists of 57 items that are stated relatively precisely, for example, "major change in financial status (a lot better off or a lot worse off)." It uses a seven point scale, ranging from extremely negative (-3) to extremely positive (plus three) (Sarason et al, 1978).

The PERI life events scale

Again this is an improvement. It contains 102 items describing a gain, a loss, or an ambiguous outcome. The items are stated clearly and organised into 11 topic areas, including work, finances, family, and health (Dohrenwend et al, 1978).

The unpleasant events schedule (UES)

Again this is an improvement, although it will take a lot longer (usually one hour) to complete. It consists of three hundred and 20 items (although a shorter, 53-item form is also available). There are a number of categories, such as sexual/marital/friendship and achievement/academic/job. The items are stated relatively precisely and are rated on a three point scale twice, first for frequency and then for adversiveness. The two ratings are multiplied, and a total score is summed (Lewinsohn et al, 1985).

The above is designed to measure stress in adults. The most widely used scale for children is the life events record which is similar to the SRRS (Coddington, 1972). The items are relevant to children, covering topics such as "divorce of parents" and "change to a different school". The values assigned to the items are dependent upon the child's age. Parents are able to fill in the Questionnaire for younger children.

Daily hassles

Kanner et al (1981) - minor stressors and pleasures of everyday life might have a more significant effect on health than the big events. - Takes account of the cumulative nature of stress.

Richard Lazarus and his associates designed this scale. It concentrates on recent stressors, the annoying things that happened to everybody everyday. The hassles are rated as having been "somewhat," "moderately," or "extremely" severe.

100 middle-aged adults were tested monthly over a nine-month period. The 10 most frequent hassles reported were:

  1. Concerns about weight
  2. Health of a family member
  3. Rising prices of common goods
  4. Home maintenance
  5. Too many things to do
  6. Misplacing or losing things.
  7. Outside home maintenance
  8. Property, investment or taxes
  9. Crime
  10. Physical appearance

In addition to the hassles scale there is another instrument, the uplifts scale, which measures the good events in life. It is reasonable to assume that experiencing events that bring peace, satisfaction, or joy would allow people to endure the hassles of daily life. Uplifts experienced in the past month are recorded on a three-point scale. The uplifts are rated as having been "somewhat," "moderately," or "extremely" strong. The 10 most frequent uplifts reported were:

  1. Relating well to spouse or lover
  2. Relating well with friends
  3. Completing a task
  4. Feeling healthy
  5. Getting enough Sleep
  6. Eating out
  7. Meeting your responsibilities
  8. Visiting, phoning or writing to someone
  9. Spending time with the family
  10. Home pleasing to you

One study tested middle-aged adults, using 4 instruments:

  1. The hassles scale
  2. The uplifts scale
  3. A life events scale that includes no desirable items
  4. The health status Questionnaire, containing questions about general health (Delongis et al., 1982).

 

There is a weak correlation between hassles scores and health status, as well as between life event scores and health status. Hassles were more strongly associated with health than life events. There was no association found between uplifts scores and health status.

Self-report measures of life events are unreliable. A study had subjects fill out a scale regarding life events they experienced during the prior year. The subjects then filled out the same Questionnaire every month for a year. Towards the end of the year the reports were quite different from the ones made at the beginning of the year (Raphael, et al. 1991).

Measurement of Stress applied to a study of abusing families  

Measuring stressors

  1. Effect of stressors - performance on simple behavioural tasks or self-report scales.
  2. Stressful life events
  3. Social environment

Measuring the stress response

Biochemical measures - various processes in the body, adrenaline, noradrenaline, and the immune system.

behavioural observation - facial expressions, rate of speech, posture, nail biting. Self report on marital satisfaction and frequency of urination.

Cognitive measures - perceived control over one's life, perceived level of arousal, mood and attitudes.

Perceived Stress Scale (Cohen, Kamarck and Mermelstein, 1983) 14 items rated on a 5 point scale. (See pp 92 - 97, Sarafino)

Problem - simple responses, unable to capture the richness of human experience.

Better scale.

Life events and Difficulties Schedule (Brown and Harris, 1989) - looks at range of issues to do with health, employment, social role, etc. Requires trained interviewers and trained judges to operate it.

Other methods of measuring stress

Above methods only provide a snapshot.
Stress varies from day to day.

Gulian et al (1990) - study of British drivers. Completed psychometric tests (e.g. Rotter's Internal - External Locus of Control Scale).

Also filled in a diary of their feelings while driving over 5 days.

Results

More stress in the evening and midweek.

Stress varied with age and experience, health condition, sleep quality, driving conditions, driver's perception of driving as stressful.

Douglas et al (1988) used diary and physiological measures
100 fire fighters from 12 stations.

Heart rate recorded for minimum of 48 hours (used portable electrocardiogram)

Results yielded a 'Ventricular cardiac strain score'.

High scores were found to correspond with number of call-outs, level of seniority, and stressful events recorded in diaries.

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