Cohen Et Al 1993 Study Evaluation Essay

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The purpose of this study was to review articles related to the psychometric properties of the Perceived Stress Scale (PSS).


Systematic literature searches of computerized databases were performed to identify articles on psychometric evaluation of the PSS.


The search finally identified 19 articles. Internal consistency reliability, factorial validity, and hypothesis validity of the PSS were well reported. However, the test-retest reliability and criterion validity were relatively rarely evaluated. In general, the psychometric properties of the 10-item PSS were found to be superior to those of the 14-item PSS, while those of the 4-item scale fared the worst. The psychometric properties of the PSS have been evaluated empirically mostly using populations of college students or workers.


Overall, the PSS is an easy-to-use questionnaire with established acceptable psychometric properties. However, future studies should evaluate these psychometric properties in greater depth, and validate the scale using diverse populations.

Stress as a bodily response (physiological model)

Let’s get something straight right from the start.  The body’s reaction to stress is old fashioned.  In the modern World, in the vast majority of stress situations the body’s response to stress causes more harm than good.  However, in the olden days, before even Mrs Ashton, Mrs Wilson and I were born (though perhaps not Mr Farren), like tens or hundreds of thousands of years ago, our present day response to stress would have been a lifesaver. 

Faced with danger such as a sabre-tooth tiger or a warring tribe down the road then a sudden mobilisation of energy in the body was useful.  Consider the typical response to stress:

  • Increased heart rate
  • Increased blood pressure
  • Relaxation of the lung’s bronchi (air channels widen)
  • Release of glucose into the blood
  • Dilation of pupils (letting more light into the eye)
  • Slowing of digestion (allowing blood to flow to muscles, heart etc).

This is referred to as the 3fs response (fright: flight or fight) and serves a simple purpose.  It is pumping oxygen and glucose around the body providing energy to the areas where it’s most needed.  If the danger persists we can fight or we can turn and run.  If danger passes then very quickly the body can return to normal and primitive man can return to taking Dino for a walk!

BUT Although our minds and behaviour have evolved since then (I speak for the majority of us here), our bodies and our biology have hardly evolved at all.  Today a typical stressor is likely to be examinations, bills, relationships, work etc.  However, our body does not distinguish between stressors, it reacts to them all in a very similar way, i.e. the way it would have done thousands of years ago faced with life threatening stressors.  (This is why Selye called it the GENERAL adaptation response).  Exams therefore cause us to mobilise energy reserves, heart rate increase etc, as I’m sure you’ve noticed.  Unfortunately the response that was supposed to last seconds or minutes now lasts for the time of the exam stress, possibly weeks or months.  It now wears the body down and becomes a life threatener rather than a lifesaver.

The Autonomic Nervous System (ANS).

This controls the functions that we have no conscious control over such as digestion, temperature and heart rate.  It can be split into two parts:

The biology of the stress response
Not the easiest topic we cover but probably not as difficult as people seem to think.  I’ll assume that you’ve heard of the pituitary and adrenal glands, though the hypothalamus may be new to you, and take it from there. The important bits.
An area in the brain called the hypothalamus controls the body’s response to stress.  This is situated right next to the pituitary gland (sometimes referred to as the master gland because it controls the others) and both are located in the middle of the brain just behind the upper part of your nose!

In the stress response the Pituitary gland does two things. 

  1. It sends nerve messages to the adrenal medulla (part of the adrenal gland)
  2. It sends a chemical ACTH to the adrenal cortex (another part of the adrenal gland).

Adrenal Medulla
Triggers the sympathetic nervous system and releases adrenaline.

This produces the 3Fs response:

  • Increased heart rate
  • Slows digestion
  • Dilates pupils
  • Releases glucose into blood

Adrenal cortex
Releases steroids into bloodstream

This causes:

  • Liver to release glucose
  • Inhibits immune response especially inflammation and production of white blood cells.
  • Convert fats/proteins into glucose.

Short-lived or persistent stress?

We have evolved two different responses to stress.  One is designed for the immediate and potentially life-threatening effects of stress (acute stress).  The other follows this up a few minutes later and is designed for longer term coping (both with the stress itself and the body’s immediate response).  This is for chronic or longer term stress.  I will consider the details shortly. 

First a very brief overview. 

SAM results in the release of adrenaline and produces a 3Fs response designed to get us out of harm’s way.

HPA follows up 10-20 minutes later, results in the secretion of cortisol which offers some longer term protection from the worst effects of chronic stress.

Although the two systems are distinct, involving different pathways, over different time scales and having very different results, clearly the two systems need to work together in our response to stress.

Increased alertness (e.g. dilation of pupils)

Increased flow of blood to the muscles and the brain (blood pressure and heart rate increase)

Increased respiration to provide muscles and brain with more oxygen

In addition, there is a slowing of digestion and increased circulation of blood clotting factors in case of injury.

Because of the electrical mediation of the message from brain to adrenal gland this all happens within the blinking of an eye.  In fact, it has been shown to swing into action before we become consciously aware of the potential threat.  

HPA (Hypothalamic Pituitary Adrenal)

This is a much slower response, designed for dealing with the effects of longer term, chronic stress.  The end product (cortisol) is often referred to as the stress hormone.

The HPA is not designed with immediate safety in mind but is there to help the body cope with the longer term consequences of stress and also the punishing effects of the SAM response. 

Here goes: If stress persists the hypothalamus kicks into action.  In particular an area called the paraventricular nucleus or PVN.  This releases CRH (corticotrophin releasing hormone)… sometimes F for factor!  CRH (or CRF) acts on the pituitary gland (anterior lobe for those interested) which in turn sends another chemical messenger ACTH (adrenocorticotrophic hormone) to the adrenal cortex. 

Finally on the biology: Don’t forget the parasympathetic response!

Once the stress is over the body has to return to normal.  Heart rate and blood pressure drop back to resting levels, blood glucose is converted back into glycogen for storage, the immune and digestive systems return to pre-stress levels of functioning. 

  Beware the question that provides a scenario of a short-lived stress that quickly disappears.  This would entail a SAM (sympathetic response) but quickly replaced by the parasympathetic response. 

  Evaluation of the Physiological Model This is clearly a very biological approach to stress.  It only considers events inside the body and sees stress as a purely physical response.  It does not consider differences between people, for example why one person’s stress is another person’s pleasure. 

Mason (1975) measured the levels of adrenaline produced by stressors in different people.  The same stressors produce different levels of adrenaline in different people depending on how they interpret the stress.  The physiological model does not consider people’s interpretations or perceptions of stress.

People without adrenal glands die when stressed unless they receive injections of cortisol (a steroid).  They have to be given training in avoiding or minimising stress!

Stress and the immune system
We have already seen that during times of stress the adrenal cortex produces steroids (called corticosteroids since they’re produced by the adrenal cortex).  These stop the body producing lymphocytes (white blood cells) that attack foreign bodies such as viruses, in the bloodstream.

The research of Janice Kiecolt-Glaser
Two pieces of research by Kiecolt-Glaser provide excellent evidence for the role of stress on the body’s immune system.

This is a fine piece of research.  Being a natural experiment (I’m sure you all noticed straight away) it is high in ecological validity.  It relates to real life, since it is a real life situation!  One weakness of the procedure is lack of control over extraneous variables.  It is difficult to conclude with absolute certainty that it was in fact the exam stress that lowered their immune systems.  It’s quite likely that closer to the examination a whole range of behaviours will have altered.  For example, time constraints leading to unhealthy eating and lack of exercise and importantly a loss of sleep due to revision or stress. 

In a similar natural experiment Kiecolt-Glaser and her team compared two groups of women.  The experimental group were caring for elderly relatives with Alzheimers, the control group were matched on a variety of measures but were not carers.  This time the immune system was assessed by time taken to heal a wound on the forearm.  The average healing time for the carers was 49 days compared to the less stressed non-carers who took an average of 39 days.

However, this again lacks tight control and does not consider other factors.  Many of the carers were on a range of medications and yet again lack of sleep is likely to be a major factor. 

Arguing couples
n an attempt at a more controlled study, Kiecolt-Glaser et al (2005) looked at the effects of marital arguments on the immune system and wound healing.

42 couples who had been married for an average of 12 years had small suction devices placed on their arms to deliberately create eight small blisters.  The tops of these were removed and a small bubble placed over the top allowing fluids to be withdrawn.

On their first such visit the couples were drawn into a positive discussion about behaviours they’d like to change.  Two months later the couples returned and the procedure repeated.  This time however, they were drawn into a more negative discussion about areas of disagreement which often provoked very strong feelings.

When tested it was found that on the second visit the blisters took a whole day longer to heal (60% longer) and that levels of the hormone interleukin-6 that controls wound healing was much higher. Women seemed to be particularly prone to the effects.

The researchers believe that stress can significantly slow down the immune response and particularly lengthen the time for healing.  Consider the implications of this research on the effects of stress following major surgery!

Other studies suggesting a negative effect of stress on immunity
Although none of the above research is tightly controlled the sheer bulk of evidence does seem to suggest that stress does have an immune-suppressing effect. 

Riley (1981) placed mice on a turntable at 45 rpm; (they must be single mice.  I’ll try this ‘joke’ again and see if you get it this year!).  This induced stress and decreased their number of lymphocytes.

Kimzey (1975) found that American astronauts who had just gone through the stress of re-entry had a lower white blood cell count.  However, Fischer et al (1972) found that astronauts had more lymphocytes (type of white blood cell) on splashdown

Stress and colds
Cohen et al (1991) carried out an impressive study on 394 participants.  They each had their stress index measured using a questionnaire that also took into account their ability to cope and their feelings about their stress.  They were then given nasal drops that infected them with one of five different cold viruses.  When tested by doctors there was a direct correlation between their stress index and the probability that they developed a cold.

Stone et al (1987) found that life experience can predict likelihood of developing a cold.  They infected 79 participants with rhinoviruses (the ones that cause colds) and recorded the chances of a cold developing.  Those developing colds typically reported either a decrease in positive or desirable events 3 to 4 days prior to cold developing, or an increase in negative events 4 to 5 days prior. 

However, some research suggests that stress, particularly acute, short-lived stress can boost the immune response:

Evans et al (1994) got students to give brief talks to other students, inducing short lived acute stress.  They then measured the levels of an antibody (sigA) that coats the mucous (snotty) membranes of the mouth, nose and lungs.  Following the talk the students had increased levels of this antibody suggesting increased immunity.

Suzanne Sergerstrom & Gregory Miller (2004): a meta analysis
They carried out a meta-analysis of 293 independent and peer-reviewed studies involving almost 20,000 participants.  They reported three main findings:

Short-term (acute) stress induced typically by a maths problem or public speaking produced a short-lived 3Fs type response that boosted the immune system.  They suggested that this would be an adaptive response designed to fight minor infections following a minor bite or scratch during a fight.

Long-term (chronic) stress resulting from real-life events such as care of relatives, refugee status or injury leading to permanent disability, resulted in the greatest suppression of the immune system and all measures of immune response such as healing and inability to fight infection were affected. 

Age and an existing problem with the immune system were significant risk factors for vulnerability to stress-related suppression of the immune system.  Both seem to make it more difficult for the body to self-regiulate. 


Stress and Coronary heart disease (CHD)

CHD is caused by a narrowing of the arteries supplying blood to the heart caused by a build up of fats in the vessels (similar to the furring up of hot water pipes).  There are two types:

·         Angina: in which blood flow is restricted.  This results in chest pains particularly following exercise.
·         Myocardial infarction: in which blood flow to part of the heart is completely blocked and can result in death.

  Stress is also a risk factor for hypertension or persistent high blood pressure.  This is an additional risk factor for heart disease as well as stroke.

Risk factors for CHD
Gender (men are far more susceptible), age (guess!), cholesterol, high blood pressure, smoking, genetics, diabetes…

Stress and CHD
Studies have suggested a link between negative life events, such as divorce and CHD and stress at work and higher incidence of CHD, particularly in men.  Occupational factors tend to include lack of control, low job satisfaction and monotony.

Early research
In an early longitudinal study begun in 1959, Friedman and Rosenman followed the progress of over 3000 male executives.  Each one completed a personality questionnaire at the outset to determine whether they were Type A or Type B.  (See later notes on personality and stress for a fuller account of the study). 

It was found that over the next fifteen years that those rated as Type A were more than twice as likely as the Type Bs to suffer from heart disease or fatal heart attack.  A possible link between stress and heart disease had been shown.

However, Friedman and Rosenman didn’t consider what aspect of the type A personality was responsible for the increased risk.  Type A behaviour is a broad church and encompasses a range of personality/behavioural types.

Cynical hostility
Recent research has found a link between cynically hostile people and CHD.  A cynically hostile person is one who has a negative view of others, seeing people as basically selfish.  They adopt a ‘dog eat dog’ attitude to life being prepared to cheat to gain an advantage, assuming that others will do the same to them.  (Phil Mitchell if you like).  Taylor (1995) found that people who score highly on cynical hostility have higher heart rate and blood pressure and produce higher levels of adrenaline

Williams (2000) gave anger questionnaires to 13,000 participants asking 10 questions such as ‘do you feel like hitting someone when you get angry?’  The participants chosen had no previous history of CHD.

This was a six year study.  At the outset none of the participants having been diagnosed with heart disease.  However, six years later 256 of the original ample had suffered a heart attack, and yes you’ve guessed, the majority of these, (over two thirds) had originally been labelled the more angry.

Although this is clearly a very similar study to the original, it does focus specifically on anger rather than the broader, poorly defined ‘type A.’

Bringing this right up to date
In very recent research, published in March 2014 and widely reported at the time, Mostofsky and her colleagues found that people are most at risk of an heart attack in the two hours following an angry outburst.  In fact, such an outburst increases the risk of CHD by five times and the risk of a stroke by three times. 

The researchers were keen to allay fears and emphasised that the risk to any one individual following a specific outburst was minor but the cumulative effect across a population was very noticeable.  Although type A or other behaviour/personality types were not mentioned in the report, it doesn’t seem that unlikely that the hostility component of type A might therefore be a predisposing factor to an angry outburst. 

Doireann Maddock, a senior cardiac nurse at the British Heart Foundation, said: "It's not clear what causes this effect. It may be linked to the physiological changes that anger causes to our bodies, but more research is needed to explore the biology behind this.”

Methodological Issues
For obvious reasons these studies have to be natural or correlational. Long term stress as a manipulated and tightly controlled IV would be highly unethical.  However, is does mean that a causal link between stress and heart disease can only be inferred, rather than proven beyond doubt. 

Williams and others have shown that stressed individuals are more likely to engage in emotion-focused stress reduction techniques (see later notes).  These include comfort eating, smoking, drinking to excess and prescription medication.  All of these are also risk factors for CHD.  Additionally, lack of sleep, poor diet and lack of exercise may also add to the risk.  See below…

Indirect effects of stress on health.

It is essential that this be considered in any essay on stress and physical health as it will guarantee AO2 marks.

Stress is associated with all manner of bad habits, for example smoking, drinking alcohol to excess, poor diet due to lack of time, lack of exercise for the same reason, lack of sleep etc…  All of these are likely to have an adverse effect on a person’s health so could cause some of the ill-effects attributed to stress per se.

Cohen & Williamson (1991) found that people who are stressed tend to smoke more, take less exercise, drink more alcohol and sleep less than others.  Because of their constant state of business they fail to find time to prepare food so tend to be more reliant on takeaway food. All of these habits can lead to ill health. 

Wills (1985) found that stressed teenagers were more likely to start smoking.  Similarly, Carey et al (1993) found that adults who had given up smoking were more likely to take it up again when stressed.

Brown (1991) found that life events were more likely to cause students to seek medical advice if the students were low in physical fitness, as compared to students high in physical fitness.

At least some of the stress-related illnesses we observe are likely to be due to indirect effects of stress rather than to stress per se. 

The special case of sleep and the immune system
Surprisingly, the regular texts don’t seem to have caught up with this one yet.

Stress, as I’m sure you all know, probably from personal experience, is not conducive to a good night’s sleep.  In the past few years it has become increasingly apparent that sleep is vital for maintaining a healthy immune system:

People who regularly awaken during their first cycle of sleep (the first 90 minutes of the night) tend to have decreased levels of those natural killer cells (NKCs).

Wright et al (2007) studied 39 sleep deprived women and found a significantly weakened NKC response.

Aho et al (2013) took a group of ‘otherwise healthy young men’ and restricted their sleep to four hours per night for five nights.  When compared to a similar group who had been allowed to sleep normally they found a substantially reduced immune response and an alteration in the expression of genes known to be involved in the immune response. 

They also reported an increase in allergic reactions and asthma. 

Given this link, it seems quite likely that at least some of the immune suppression reported by the likes of Kiecolt-Glaser and others, in response to stress, is in fact an indirect response caused by stress-related insomnia. 

Sources of Stress

Life events (Social Readjustment Rating Scale: SRRS)

Holmes and Rahe (1967) were two hospital doctors who noticed that many of the patients that they visited on their rounds had suffered life events causing disruption to their lives in the previous year.  They decided to construct a questionnaire to examine the possible link between life changing events and physical ill-health. 

  1. They examined the medical records of over 5000 patients
  2. They compiled a list of 43 life events
  3. They rated these in order of the time it would take to get your life back to some semblance of normality following the event
  4. They gave ‘marriage’ an arbitrary score of 500 and got others to rate the other events in comparison to this.  They averaged out the scores and divided them by 10, so in the final scale ‘marriage’ has a score of 50.
  5. The scale starts at 100 LCUs (Life Change Units) for ‘death of a spouse and ends with 11 LCUs for ‘minor violation of the law.’
The scale was tested on different groups of people to determine its relevance.  Patients would add up the score for each life event and this would be their total LCU.  They believed that a score of over 300 meant an 80% chance of developing a serious physical illness in the following year.  Examples they suggested included TB and diabetes as well as psychological conditions such as depression and anxiety.

Testing the SRRS

Rahe et al (1970) tested 2700 male naval personnel on board three American cruisers just before they set sail.  During their seven months tour of duty the sailors kept health records.  A correlation of +0.118 was found between LCUs and ill-health.  Clearly this study is ethnocentric and androcentric.  Presumably naval personnel were chosen since accurate medical records would be available and regularly updated during the men’s tour of duty.  The correlation found is small but due to the size of the sample (2700) is significant.  However, it does suggest that the link between life events and ill-health is relatively minor, and of course being a correlation, we cannot prove a causal relationship. 

Evaluation of the SRRS

Individual differences: the life events in the list will have different meaning and cause different amounts of disruption to different people.  For example the effects of divorce will depend on how long the couple have been married, whether or not children are involved, whether the person is escaping a violent partner etc…

Cause and effect: the scale implies a correlation between stress and ill-health, however, as I’m sure you must have realised by now correlations do not prove cause and effect.  All manner of other reasons could be used to explain the link.  Ill-health could be causing the stress, or the life events.  For example a heart attack could cause loss of job, major changes in standard of living resulting in break up of marriage etc.  Illness and medication are likely to result in change in sleeping and eating habits. 

Van Os et al (2001) reported a strange take on the cause and effect issue.  Those most at risk of stress (they score high on neuroticism) when assessed at the age of sixteen, were more likely to experience more life events in later life.  Perhaps stressed people create more life events?  More likely of course, they are more likely to report more life events.  We therefore have a situation where, contrary to Holmes and Rahe’s assertion, stress is causing life events and not vice versa. 

Hassles and Uplifts

Generally our everyday feeling of being stressed can probably be attributed more to minor, irritating problems than to the rarer major life events.  Some research has found that hassles have a greater correlation with ill-health than do the seemingly more serious life events.

Examples of hassles and uplifts (Kanner et al 1981):

Studies into the effects of hassles on stress and health

De Longis et al (1982)

100 participants (all over 45) were asked to complete four questionnaires each:

  1. Hassles scale (117 items)
  2. Uplifts scale (135 items)
  3. Life events questionna
  4. Health questionnaire.

The results were probably not expected: hassles correlated with ill- health whereas uplifts and most surprisingly life events did not. However, it has been shown by others that older people (if we class over 45 as older) tend to suffer less from hassles than younger people so the findings are difficult to generalise.

Bouteyre et al (2007) got first year French University students to complete two questionnaires, one measuring life events, the other symptoms of depression (Beck’s Inventory). It was found that students showing the most depressive symptoms were also likely to be suffering from the most hassles.  Clearly this is a correlational study so cause and effect cannot be established.  Of course it could be that feeling depressed and having negative thoughts makes us focus more on negative events such as hassles.

However, most studies do seem to agree that hassles are a bigger threat to our health than the much bigger life events.

Possible reasons for hassles being a bigger issue than life events:

Social and emotional support
Flett et al (1995) reported that people going through major life events will be more likely to receive help and support than people suffering from hassles.  However, this was based on participants being given artificial scenarios and being asked to judge the amount of support that would be provided.  Clearly this lacks some external validity and participant’s answers will be based upon expectation rather than real-life experience. 

Accumulation effect
Lazarus (1999) suggests that hassles tend to build up and act as a source of persistent irritation which can then lead to anxiety and even depression.

Amplification effect
It could be that big events make us more susceptible to the effects of trivial hassles so the two work hand in hand to create stress.  Having suffered a major event we are left feeling more vulnerable to hassles and problems multiply.  Think back to the transactional model.  Perhaps life events alter our perception of our ability to cope.

Evaluation of hassles research
As with life events, individual differences are not considered.  We all perceive and react to stress differently, some people seemingly being able to cope better than others, and again these are not considered.

Cause and effect.  Yet again the studies are correlational so do not prove that the stress is causing the illnesses.  For example just before a cold we may feel more hassled, but this could be because the virus is already having its effect, leaving us tired and less able to cope with everyday events.  That is the illness is actually causing the hassle!

Retrospective: much of the research ask participants to think back over the hassles that they’ve faced in the past month.  As we saw with the ‘love quiz’ in unit one, this is very unreliable method of gathering data.

Occupational stress

This is a favourite topic for examination questions as well as being an important issue for workers around the World.  Recently stress has overtaken the common cold as the main reason for absence from work.  Likely questions will focus on ‘factors’ involved in workplace stress, by which the Board mean ‘control,’ ‘workload,’ ‘role conflict’ etc. and research into work-related stress which requires coverage of Marmot et al and similar studies.  In an attempt to facilitate answers to these questions I intend to briefly describe factors and then provide supporting studies for each one.  However, many studies, such as Marmot, can be used as evidence for more than one factor.  Where this is the case I’ll try to point out those possible factors.  I’ll conclude with a general evaluation of the research cited and a brief discussion of individual differences such as personality.  This will lead nicely into the next section.

Factors involved in workplace stress

1. Role conflict
This is a common form of stressor and arises when the job requires you to behave in a way that is at odds with your own desires or beliefs.  For example working overtime may be at odds with your role as parent.  Similarly someone in middle management may find it difficult to balance the needs of their superiors for higher output with the needs of their staff for a shorter working week.

Pomaki et al (2007) found that role conflict was responsible for emotional exhaustion, depressive symptoms and even some physical illnesses in a study of hospital doctors.

2. Environmental factors
These include any aspect of the working environment that is likely to cause stress; most obvious examples include noise, temperature, vibration, lighting and overcrowding.

Although people can cope reasonably well with noise it does appear to cause some impairment in performance, particularly if the noise is unpredictable.  Glass et al got 60 participants to complete cognitive tasks such as word searches under one of four conditions:

The researchers concluded that we can adapt to high noise levels but this is more difficult if the noise is not constant or is unpredictable.

The stress of overcrowding has been studied in other species particularly rats where it has lead to bizarre behaviours such as parents eating their offspring.  Freedman et al (1975) found a correlation between high density living conditions such as inner cities, and admissions to psychiatric hospitals.  Yet again this is a correlation so does not prove c_____ and e_____.  Perhaps you could think of some other reasons, other than overcrowding to explain why inhabitants of inner cities are more likely to be diagnosed with mental illness.  Clues perhaps in the next topic!

Work overload
Breslow and Buell (1960) found that employees working more than 48 hours a week were twice-as-likely to develop CHD than those working 40 hours a week.

This study highlights a number of risk factors and can be used as evidence for responsibility, lack of control, repetitive nature of the work and for social isolation.  Environmental factors such as noise likely to have added further to the cocktail of stressors.

Effort-reward imbalance
Ever got that feeling that all your hard work isn’t being recognised or that you don’t feel you’re getting the rewards that you deserve?

Kivimaki et al (2002) published the results of a 25 year study of 812 workers.  Those with an effort-reward imbalance were twice as likely to suffer from cardiovascular disorders such as CHD than those who felt that they were being recognised for their efforts.

Smith et al (2005) got similar findings and put the results down to increased anger caused by the feelings of injustice.  This could be compared to Friedman and Rosenman’s findings of hostility and anger being related to CHD with type A behaviour.

A sense of control in the workplace is vital if stress is to be avoided.  The study by Glass et al earlier can be used as evidence.  In the follow up procedure, those given a button to control the noise performed much better on the tasks set and scored much higher for persistence on difficult or impossible tasks.  However, the study below is THE one to use.

Other studies for control
Cobb and Rose (1973) analysed the medical records of over 4000 air traffic controllers (considered to be an extremely stressful occupation) and found that they were at significantly greater risk of developing hypertension (long term high blood pressure).  In fact there was a positive correlation with those working in airports with greatest airplane activity suffering the highest levels of hypertension.  Other health issues include increased risk of ulcers and of diabetes.  These also tended to occur at a younger age than would normally be expected. 

Again ATCs experience a variety of risk factors including lack of control due to the unpredictable nature of their job.  They also have to maintain constant vigilance resulting in high job strain and, of course, have huge responsibility, dealing as they are with the lives of thousands of airborne passengers and crew.

The Whitehall Study
They found that workers with less control were four times more likely to die of heart attack than their colleagues with more control.  In addition they were more likely to suffer from other stress related illnesses such as cancers, ulcers, stomach disorders and strokes.  Even when other possible contributory factors such as diet, smoking, social support etc. had been taken into account the additional risk remained! 

The conclusion was obvious, that lack of control seemed to be associated with illness and they recommended that employers gave their staff more autonomy and control.

The initial study also found that the mandarins at the top of the tree (nothing to do with citrus fruit) also suffered higher levels of stress which was attributed to workload rather than issues of control.  However, in a follow up study five years after the first, this was seen not to be an issue or contributory factor to stress. 

Criticisms of this study:
Since the method is correlational it can only be said that there appears to be an association between low control and stress-related illness.  It cannot be assumed that low control is causing illness!   It could be that workers with poor health are less likely to achieve the higher grades where control is greater.  This would explain the findings just as well.

Workers filled in self-report questionnaires which are notoriously inaccurate and prone to participant reactivity (see notes on research methods).  Basically, if the workers suss what the researchers are looking to find they may answer questions accordingly.  Similarly the personnel managers assessing people’s jobs may do the same!

It is also worth pointing out that control was not the only variable separating lower grades from those higher up.  Typically those higher up the scale have more interesting jobs with greater variety of tasks.  There are also greater opportunities for contact with others so social support could be an issue. 

Although Marmot concluded that workload was not an issue, other studies seem to disagree.  For example the Johansson sawmill study outlined below:

Job strain and CHD
Karasek et al (1982) followed 900 workers for ten years.  A combination of job titles and self-report questionnaires were used to measure job demand and control. 

High job strain was considered to be the result of high demand jobs but with low control.  Those workers with high job strain were 1 ½ times more likely to develop CHD during the study.

Johnson and Hall (1988) studied 14,000 Swedish workers

They measured:

  1. Work control: the variety of tasks, control of holidays, ability to plan work etc
  2. Social support: chances to talk to others, number of out of work get-togethers etc.
  3. Psychological demands of the jobs such as how hectic and how demanding
  4. Their cardiovascular health

Similar to those of Karasek: those involved in high demand/low control jobs were most likely to develop cardiovascular problems.  Fewer chances for social contact seemed to be a particular risk factor.

More recent versions of the job strain model now include social support as a major factor.

Both of the above studies rely heavily on self-report techniques making them less reliable.  A persons perception of their workload may not be entirely accurate or unbiased!

The data is also largely correlational with all manner of variables, such as life outside of work, not being considered.  It is therefore impossible to be certain that job strain per se is the cause of the increased levels of CHD.

Very recent research by Dr Michelle Albert (Nov 2010)
Over 17,000 women in Boston, USA were studied over a period of ten years.  Those in high strain occupations had a 40% greater risk of cardiovascular disorders and 88% increased risk of suffering a heart attack.  She also reported that job insecurity and the worry of unemployment increases the chances of CHD and hypertension.

Ellen Mason of the British Heart Foundation added that the precise link between stress and CHD is still unclear, but there is growing evidence that high stress weakens the artery walls. 

This was an unusual study in that it considers the risk of CHD in women. 

Individual differences
Again we come back to the transactional model of stress.  This emphasises the importance of individual differences, especially In our perception of stress and our ability to cope.  One person’s stress is the thrill seeker’s pleasure.  We all react differently and have different perceptions of our ability to cope.  This tends not to be considered in the above studies. 

Folkman and Lazarus’ Transactional Model
Another crucial factor that needs to be considered the person’s view of the stressor and also of their perceived ability to cope.  Folkman and Lazarus, in their transactional model believes our cognitive appraisal of these two factors determines whether a situation is stressful or not.  If our perceived ability to cope outweighs the perceived threat we remain stress-free.  It’s only when the perception of the stress outweighs our perceived coping that we feel the anxiety of stress.  Think of your attitude to examinations.  If you prepare and increase your coping ability and are confident in your preparation, you’re likely to feel less stressed than if you enter the hall unprepared. 

This brings us nicely to the next section.

Personality and the stress response

Generally we could differ because of personality, gender, social class, ethnicity, age, genes, life experiences etc.  In terms of our response to stress we’ll concentrate on personality

Type A behaviour and CHD
In the 1950s two cardiologists, Meyer Friedman and Ray Rosenman, believed they had discovered a behaviour pattern, possessed by some of their patients, that predisposed the risk of heart attack.  They called it Type A. 

Brief description of the behaviour types:
  • Type A: competitive, ambitious, impatient, striving for achievement, aggressive and hostile, fast talking.
  • Type  B: usually described in terms of a lack of type A i.e. relaxed, laid back, non-competitive, non-aggressive etc. 

Type A/B ness is usually assessed using a questionnaire but can also be observed when participants are deliberately kept waiting or wound up in some other way.

To test their hypothesis that type As were more prone to CHD they embarked on what was initially designed to be an eight year longitudinal study, described below.  The study began in 1959.

Friedman & Rosenman’s Western Collaborative Group Study (1974)

3200 participants (all men) aged between 39 and 59 were given questionnaires.  From their responses, and from their manner, each participant was put into one of three groups:

Type A behaviour:  competitive, ambitious, impatient, aggressive, fast talking.

Type B behaviour:  relaxed, non-competitive.

Type C behaviour:  ‘nice,’ hard working but become apathetic when faced with stress.

Eight years later 257 of the participants had developed CHD. 

70% of these had originally been classed as type A.

Friedman & Rosenman did not specify what aspect of type A behaviour might be responsible for CHD.  Matthews et al (1977) reviewed the original data and found that it was ‘the negative behaviours’ such as hostility that seemed to be responsible.  They put this down to the increased activity of the sympathetic nervous system that weakens the heart and arteries.  Myrtek (2001) also cited hostility as the key risk factor.

Are the affects direct or indirect?  People who demonstrate type A behaviour may be more likely to smoke, drink excessively and lead generally less healthy lifestyles.  Perhaps this, rather than the behaviour type itself causes CHD.

Issues related to type A and type B
Strictly speaking the researchers spoke of type A and Type B behaviour but is widely viewed now as a personality type as well. 

In 1982 Ragland and Bland carried out a follow up study on Friedman and Rosenman’s initial sample.  Since the start of the study back in 1959 a total of 214 men had died of CHD.  However, there appeared to be no additional risk amongst the type As, seeming to question the original findings in 1974.  Age and smoking, as expected, appeared to be by far the biggest risk factors. 

As already mentioned in the section on CHD: In very recent research, published in March 2014 and widely reported at the time, Mostofsky and her colleagues found that people are most at risk of an heart attack in the two hours following an angry outburst.  In fact, such an outburst increases the risk of CHD by five times and the risk of a stroke by three times. 

The researchers were keen to allay fears and emphasised that the risk to any one individual following a specific outburst was minor but the cumulative effect across a population was very noticeable.  Although type A or other behaviour/personality types were not mentioned in the report, it doesn’t seem that unlikely that the hostility component of type A might therefore be a predisposing factor to an angry outburst. 

The often forgotten Types B, C and D

Type D, originally described by John Denollet following observation of his cardiac patients.  Type Ds are prone to stress, anger and tension and generally have a pessimistic outlook.  They tend towards low self-esteem are socially inhibited and suppress emotions.   Type D is tested using a 14 item questionnaire: seven questions assessing negative affect and seven measuring social inhibition.  A score of ten or more results in the person being described as a ‘D.’  Denollet estimated that 21% of the population are type D but that amongst his cardiac patients this rises anything up to 53%. 

However, people who score high for negative affect are known to over-estimate their symptoms of stress.  Since NA is such a large component of type D it’s likely that stress levels are being overestimated.  There’s also the usual issue of causality.  Is a long term illness provoking the personality change?

According to Kobasa there are three characteristics of the hardy personality:

  • Control: hardy individuals see themselves as being in charge of their environment
  • Commitment: hardy individuals get involved and tackle problems head on
  • Challenge: hardy individuals see change as a challenge rather than as a threat 


Kobasa (1979) herself tested 800 US executives using Holmes and Rahe’s SRRS to determine stress level.  Out of the initial sample about 150 were showing high levels of stress.  However, many of these were not showing any increased signs of ill-health, as would be expected with such high life events scores.  Kobasa concluded that there must be a third factor causing this discrepancy and attributed the differences to the hardy personality.  Generally those scoring high on the SRRS but showing little ill health were also scoring high on hardiness. 


As we saw earlier, there are many issues with the SRRS.  Research suggests that it isn’t a particularly good predictor of ill health anyway. 

Methodology: The research was based upon self-report questionnaires which are not always reliable and are often completed retrospectively.

Cause and effect: yet again because the study is correlational can we be sure that it was hardiness that had the beneficial effects on the managers’ health?  Perhaps as (Alfred & Smith 1989) have suggested, hardy people are more likely to look after their health.

Klag and Bradley (2004)
In a major study, the researchers took a variety of measures including hardiness, neuroticism, stress, symptoms of illness and approach or avoidance style of coping.

As would be predicted by Kobasa they did find a negative correlation between hardiness and stress-related physical illness.  However, when analysed closer they found that this only worked for the commitment and control components of the hardy personality.  Challenge seemed not to relate to incidence of physical illness. 

However, when neuroticism was taken into consideration these effects disappeared, leading the researchers to conclude that it was in fact neuroticism, not hardiness, that was creating the effect.

There was also a sex difference.  Hardiness only appeared to offer a buffering effect against the stress in men.

Hardiness or negative affect (NA)?
Like Klag and Bradley, some have questioned whether the concept of hardiness is useful.  Watson and Clarke (1984) described positive and negative affect traits.  Negative affect (NA) is the tendency to be more nervous, fearful and guilty and generally report more distress.  Essentially, this is what Klag and Bentley referred to as neuroticism.  Confronted with stress and adversity they are more likely to dwell on the negative consequences.  A number of studies (e.g. Anderson 1997) has shown that hardiness does correlate closely with negative affect (measured using PANAS).

Perhaps individuals who score highly in negative affect are likely to be least hardy so suffer greater ill-health as a result of stress.

Increasing hardiness

Kobasa has designed a training programme designed to increase hardiness.  It follows the usual three stage process that you would expect for a treatment essentially based on the cognitive behavioural technique.

  • Focusing: Patients (or should that be clients?) are encouraged to focus on the physical symptoms of their stress so they know when intervention is needed
  • Reconstructing stressful situations: Relive recent experiences and consider what went well and what went less well.
  • Compensating through self-improvement:  Look for challenges that are within your coping ability.

Although the syllabus no longer requires a knowledge of this technique, that fact that it exists, and has had some success in treating stress, would suggest that Kobasa’s underlying theory of hardiness might have some validity. 

Stress can be good for us: Taken from BBC News website

A short burst of stress, such as that caused by sitting an exam, may strengthen your body's immune system. But long-term stress, such as living with a permanent disability, may render you less able to fight infections, say the study authors.

Dr Suzanne Segerstrom and Dr Gregory Miller report their findings in the journal Psychological Bulletin. Scientists have known for some time that stress can have a negative effect on the body.  They looked at about 300 scientific papers published on the subject, involving almost 19,000 people.

Stressful situations that lasted only short periods appeared to tap into the primeval 'fight or flight' response, which dates back to when early man was threatened by predators.  This response benefited the person by boosting their body's natural front-line defence against infections from traumas such as bites and scrapes.  But long-term anxiety had the opposite effect.

Situations that caused permanent stress and turned the person's world upside down were damaging to health.  These stressful events, such as caring for someone with dementia, appeared to wear out the immune system, leaving the person prone to infection. The important factor appeared to be knowing that the event causing the anxiety would end soon.

Phillip Hodson, a fellow of the British Association for Counselling and Psychotherapy said the research reinforced what is known.  "We all need some pressure in life. Stress is there to make sure you do your best in a challenging situation, whether it is running away from a sabre-toothed tiger or having to confront a difficult interview.

Coping with Stress

Stress has become a major issue in recent years and few topics have received so much attention, either in serious scientific journals or in popular publications such as magazines.  There has been TV series such as ‘Stressed Eric’ and the paperback ‘Little book of calm’ that sold over 2 million copies in 2000.  In the workplace stress has become a major concern of managers and Company bosses following successful litigation by employees claiming harm done by unnecessary exposure to stress.  Stress management or stress reduction is now a multi-million pound business and many methods of coping have been devised, some with more success than others. 

At the outset it is important to make a distinction between various approaches.  Methods of coping could, for example, be split between:

Emotion-focussed is a palliative approach that tries to improve the way we feel about the stress but without tackling the problem head on.  These include denial that a problem exists or pretending an event never happened, displacement of anger in other directions or venting emotions through crying for example.  Alcohol is also an emotion-focused approach.

Problem-focussed methods deal with the root causes of stress and attempt to improve the stressful environment the person is experiencing, for example speaking to the boss who is making life difficult or by time management. 

Main effects hypothesis
Generally it seems to be assumed that problem-focused is the more effective method of coping.  Penley et al 2002, in a study of nurses, found that those using problem-focused techniques were generally blessed with better health.

Goodness of fit hypothesis
If the stressor is perceived as controllable then we are indeed likely to prefer problem-focused methods.  Not surprising really I suppose; we can do something about it so we do!  However, if the stressor is perceived as being beyond our control then we fall back on emotion-focused methods.  We can’t tackle the issue head on so we make the best of a bad deal!

Research tends to favour the more flexible goodness of fit hypothesis:

Folkman and Lazarus found that students use problem-focused methods when preparing for exams but are more likely to rely on emotion-focused methods when waiting for results. 

A study of people living close to the Three Mile Island nuclear power station that almost went into meltdown in the early 1980s found that those using emotion-focused methods coped much better, presumably because it was completely out of their control.

Evaluation of research
Unfortunately it isn’t always possible to separate the two coping strategies.  Making a plan for example would seem at first glance to be an example of problem-focused coping, but making a plan also makes you feel better, as though you are doing something useful.  This presumably would be classed as emotion-focused.

Much of the research is also correlational so it is difficult to assume cause and effect.  It is very difficult to randomly allocate participants to two categories since people have their own way of dealing with stress.

Following on from this and perhaps not surprising, hardy personalities prefer the head on problem-focused methods whereas less hardy tend to plump for emotion-focused.

Physiological and psychological methods of stress reduction

Physiological methods (all the Bs)

A number of categories of drug have been used.  In the olden days the drugs of choice were barbiturates but these had a number of side effects. 

Today there are two main categories (and also begin with ‘B’):

Benzodiazepines (Librium and valium)
The body has its own built in mechanism to reduce arousal.  The chemical GABA (gamma amino butyric acid) acts on the neurons of the nervous system to create calm and suppress excitatory firing.  Release of GABA at the synapse triggers receptors on the post-synaptic neuron that opens up channels.  This allows the inflow of chloride ions.  As chloride builds up it prevents other neurotransmitters such as serotonin from being able to fire the neuron. 

Benzodiazepines increase the effectiveness of GABA so act to increase its calming influence. 

Stress as a bodily response

The body’s response to stress, including the pituitary-adrenal system and the sympatho-medullary pathway to outline.

Stress related illness and the immune system

Stress in everyday life

Life changes and daily hassles

Workplace stress

Personality factors including type A behaviour

Distinction between emotion-focused and problem-focused approaches to coping with stress

Psychological and physiological methods of stress management including cognitive behavioural therapy and drugs.

Sounds complicated I know and there is some big and ‘sciencey’ words.  Basically this looks at why we developed a stress response and how it prepares us to deal with dangerous situations that the World might have in store.

Considers why, because of our modern, civilised lifestyle that the stress response can sometimes do more harm than good.  Particularly looks at the link between stress and heart disease and the effects of stress on our immune system.

Considers the more stressful big life events such as divorce, moving home etc. and minor hassles such as losing keys, getting stuck in traffic and so on.

Work is a major source of stress with issues such as burn-out, too much or too little control and workplace relationships being big issues.

To what extent does our personality affect how well we cope with stress?  Are assertive, competitive people more likely to suffer as a result?  What is a hardy personality and how does it help?

We can tackle stress at its source or merely do things to make ourselves feel better about it.

Having looked at the dangers and the causes we finally consider ways to reduce stress.  Cheap and easy ways such as taking a few pills or more complex psychological methods that don’t have the same side-effects.

The adrenal glands are located, as their name suggests, just above the kidneys.  ‘Renal’ is Latin for kidney and ‘ad’ means just above.   Obviously adrenalin is produced in the adrenal glands.

Note: our American cousins refer to adrenaline as ‘epinephrine.’  They prefer the Greek, with nephron being Greek for kidney and ‘epi’ meaning close to. 

The top diagram shows the location of the cortex and medulla.
SAM (sympathetico adrenal medullary) or Sympayhomedullary pathway

Call it by its Christian name by all means, but the full name does explain what is involved.  It is a sympathetic response in that it creates arousal and activity within the brain and body and it involves the adrenal medulla (see above).

On first becoming aware of a stressor the hypothalamus activates the sympathetic branch of the ANS.  Noradrenaline is released to all parts of the body but specifically messages are sent via neurons to the adrenal medulla.  Remember: FIREMAN SAM for a FAST response J.
The adrenal medulla secretes adrenaline which in turn produces the 3fs response:

The higher centres of the brain (cortex) become aware of stress or danger.  These pass the message on to the hypothalamus which controls the endocrine or hormonal system of the body.

The hypothalamus releases a chemical CRF (cortico-trophin releasing factor) which stimulates the pituitary gland into action.

The anterior lobe of the pituitary gland now secretes a hormone called ACTH (adreno-cortico trophic hormone).

ACTH acts on the adrenal cortex (as the name suggests) causing it to secrete cortisol. 

Cortisol results in

  • Release of energy (glycogen)
  • Lowered sensitivity to pain
  • Lowered immune response
  • Impaired cognitive functions such as concentration
  • Slowing of digestion.
The whole process reaches a peak after about 20 minutes of the initial stressor. 

The system is self-regulating with the hypothalamus and pituitary glands monitoring the levels of cortisol and increasing or decreasing levels as necessary.

Student exam stress

In her most famous study she took blood samples from 75 student volunteers, either:

·         One month before their examination (control reading) or

·         On the first day of their examinations (stress reading)

They also completed a questionnaire designed to assess their psychiatric state, level of loneliness and number of life events.

Results/conclusions: In the stressed condition they had significantly fewer natural killer cells.  She also found that loneliness, lots of life events and problems such as depression were also associated with a weakened immune response.
As pointed out there is a clear physiological link between stress and CHD.  The 3Fs response has the following adverse effects on the circulatory system:

Constriction of the arteries increasing blood pressure.

Increased blood flow wearing down the arteries

Release of fats into the bloodstream increasing the risk of blockage (artherosclerosis).

You may have noticed that the SRRS contains potentially positive life events such as Christmas, holidays and change in personal finances (which could be positive as well as negative).  It therefore seems fair to assume that what the SRRS is measuring is change in a person’s life that is leading to stress. 

Michael and Ben Zur (2007) looked at 130 people who had recently divorced or been widowed*.  Levels of ‘life satisfaction’ had not surprisingly dipped following death of the spouse in the widowed group.  However, in the divorced group the opposite was recorded with people reporting an increase in ‘life satisfaction.’  This would seem to support the idea that the scale is measuring change rather than negative issues following life events. 

Not surprisingly however, it does seem that negative or unpredicted life events are most harmful.

Jail is spelt gaol in English!

Rising price of goods
Too many things to do
Misplacing or losing things
Physical appearance
Weight problems


Completing a task
Feeling healthy
Getting sufficient sleep
Eating out
Spending time with the family
Meeting your responsibilities

Unpredictable noise

Made more mistakes and were less persistent on the task.

Predictable noise

Participants adapted to the noise and made fewer mistakes.  Had lower arousal levels (GSR).

Johansson et al (1978) studied a small group of workers in a large sawmill.  Their job was ‘finishers’, i.e. they were the final link on a conveyer belt system.  The rate at which they worked determined the output of the mill so their job was very responsible. 

Sources of stress included: responsibility for the mill’s output, responsibility for the pay of other employees (since pay was linked to productivity), working in isolation, so didn’t have others to share problems with, little control (since they worked on a conveyor belt), highly skilled but repetitive work.

The researchers’ measured their stress hormones (adrenaline and noradrenaline) and patterns of illness. 

Findings:  They had much higher levels of absenteeism due to illness and higher levels of adrenaline in their urine, but only on work days. 

Conclusion:  The researchers recommended that the finishers should move to a salary structure (i.e. pay not based upon output) and should be allowed to rotate jobs with other workers.
Marmot et al (1997) began with the hypothesis that control was negatively correlated with stress-related illness; that is as control decreases the level of illness increases.

Over 10,000 civil servants were investigated over a period of three years.  Researchers assessed the level of job control by self report questionnaires and by assessments by personnel managers and this was then compared to levels of stress related illness

                                                              Michael Marmot
Type B (for information only) is not related to any particular health issue.  My fellow Bs are relaxed, emotionally intelligent, tend to be more conscientious and generally avoid risks in stressful situations.

Type C, originally described by Gabor Mate are ‘deniers of feelings.’  They appear relaxed and unemotional but lack assertiveness and tend towards learned helplessness and hopelessness.  Mate believes type Cs are more at risk of autoimmune disorders such as arthritis and asthma.  Others believe they’re also more prone to cancers!


Suzanne Kobasa believed that people with a hardy personality were less likely to see events as stressful.  Eight hundred business executives of a large US company were tested using the SRRS.  Those who scored highly were then examined and split into two groups; those who were frequently ill and those who were rarely ill.  She found a difference in personality between the two with those reporting few illnesses being described as hardy.

Did Ollie have a Hardy personality?


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