Individual differences in stress: personality types A, B and C and associated behaviours; hardiness, including, control, commitment and challenge.

Description, AO1 – Individual Differences and Stress

Definition: Personality: The term ‘personality’ is difficult to define, but a typical definition sees an individual’s personality as their characteristic ways of behaving, thinking, feeling, reacting and perceiving the world. Personalities are often seen as relatively stable over time and based on this, psychologists have attempted to classify people into ‘personality types’. These personality types may then be used to see if certain personality types are more susceptible to becoming stressed and, as a result, more likely to develop stress-related illnesses.

There are two main groups of ‘personality types’ when it comes to assessing how susceptible people’s personalities are to becoming stressed. These are:

  • Type A: According the Friedman and Rosenman, possess three characteristics, (1) competitiveness and achievement striving (2) patience and time urgency (3) hostility and aggressiveness These characteristics are believed to lead to raised blood pressure and raised levels of the stress hormones – linked to ill-health, specifically CHD.
  • Type B: In contrast, Type B was proposed as relatively lacking in these characteristics and tend to be more,

    (1) Patient

    (2) Relaxed

    (3) Easy-going These behaviours are believed to decrease an individual’s risk of stress-related illness.

  • Aim: Friedman and Rosenman (1959) aimed to determine whether there was a link between stress-related illnesses and personality type.
  • Procedure: 3154 healthy men aged between 39 and 59, living around San Francisco were studied in a longitudinal study via structured interviews. They devised a set of 25 questions to assess the way a person typically responds to everyday pressures that would create feelings of impatience, competitiveness or hostility. For example, they were asked how they would cope with having to wait in a long queue or working with a slow partner. In addition, the interview was conducted in a provocative manner to try to elicit type A behaviour, for example, the interviewer might speak slowly and hesitantly, so that a type A person would want to interrupt. Participants were then classed type A or type B on the basis of the results.
  • Findings: They found that eight and a half years later, twice as many type A individuals had died of cardiovascular problems than type B’s. type A’s also had higher blood pressure and higher cholesterol than type B’s.
  • Conclusion: They concluded that aspects of a person’s personality are linked to CHD and the key factor may well be stress.


Evaluation, AO3 of Friedman and Rosenman’s Research:


(1) Point: Further evidence supports Friedman and Rosenman’s (1959) findings that there is a relationship between personality type and the onset of stress-related illnesses. Evidence: For example, Williams et al (2000) found that those participants who had scored highest on an anger questionnaire (an aspect of type A personality) were 2.69 times more likely to have a heart attack than those with lower anger ratings. Evaluation: This is a strength as it supports Friedman and Rosenman’s conclusion that aspects of personality are linked to illness and the link is thought to be stress.


(1) Point: Friedman and Rosenman’s study can be criticised for using a biased sample. Evidence: For example, Friedman and Rosenman used a sample of 3154 males aged between 39 to 59 years old. Evaluation: This is a weakness because Friedman and Rosenman’s research lacks population validity and as a result, the findings from the study cannot be generalised to the entire population because it is possible that women may deal with stress in a different way to men, so type A women may not necessarily experience similar outcomes to type A men..

(1) Point: Friedman and Rosenman’s study can be criticised for not taking individual differences into consideration. Evidence: For example, there are many individual differences and lifestyle variables that can affect vulnerability to heart disease. A person with a type A personality may be more inclined to smoke/ drink alcohol as an attempt to calm them down/relax them after a period of stress. Evaluation: This is a weakness because, although some of these individual differences/variables were controlled for in Friedman and Rosenman’s research, it is possible that some important variables (EV’s) were missed and as a result, a direct relationship between personality type and the development of stress related illnesses cannot be established.


Description, AO1 of Research Into The ‘Hardy’ Personality: Kobasa (1979)

Hardiness Definition: Although type A behaviour is claimed to be a risk for CHD, many type A individuals appear resistant to disease. Kobasa et al (1977) suggested that some people are more psychological ‘hardy’ than others. The hardiness personality includes a range of characteristics which, if present, provide defenses against the negative effects of stress.

The Three C’s:

Control: Hardy people see themselves as having a strong sense of control over events in their lives and feel that they can overcome their experiences.

Commitment: Hardy people are highly committed or more deeply involved. In whatever they do they have a strong sense of purpose.

Challenge: Hardy people view life challenges as problems to be overcome as opposed to viewing them as threats or stressors. They enjoy change as an opportunity for development.

Research into the ‘Hardy’ Personality

Procedure: Kobasa (1979) studied 800 male American business executives assessing stress using Holmes & Rahe’s SRRS (a measure of life events which is thought to indicate stress levels). Approximately 150 of the participants were classified as having high stress according to their SRRS scores. Participants were also asked to list the number of illness episodes that they had experienced in this time. Of these, some had a high stress/low illness record (86 participants) whereas others had a high stress/high illness record (75 participants). This suggests that something else was modifying the effects of stress because individuals experience the same stress levels had different illness records. Three months later, participants were asked to complete a series of personality tests, which included assessment of control, commitment and challenge.

Findings: The individuals who are in the high-stress/low-illness group scored highly on all 3 of the hardiness characteristics, whereas the high-stress/high-illness group scored lower on these variables.

Conclusion: Kobasa proposed the notion that a hardy personality type encourages resilience and therefore helps an individual to cope with stress. This suggests that hardy personality type is linked to stress levels and that a hardy personality provide defenses against the negative effects of stress.


Evaluation, AO3 of Research into the Hardy Personality:


(1) Point: A strength of the research into personality types and stress is that further research has supported Kobasa’s findings surrounding the hardy personality. Example: For example, Lifton et al (2006) measured hardiness in students at 5 U.S. Universities to see if hardiness was related to the likelihood of their completing their degree. The results showed that students scoring low in hardiness were disproportionately represented amongst the drop outs and students with a high hardiness score were most likely to complete their degree. Evaluation: This is a strength as it supports Kobasa’s findings that a person scoring high on a scale measuring hardiness is more successful in coping with the negative effects of stress.


(1) Point: Kobasa’s research can be criticised for relaying on self-report questionnaires to collect data about the hardy personality. Example: For example, individuals may provide incorrect information about their stress levels in an attempt to please the researcher/give the researcher the results they are expecting (for example, participants may over estimate holding characteristics of control, challenge and commitment due to the fact that these are desirable characteristics to have). Evaluation: This is a weakness as the study may not be accurately measuring what it is intending to measure which would result in a low level of internal validity and so the findings would not be able to be generalised beyond the research.

(2) Point: Kobasa’s study can be criticised for using a correlational analysis to measure the relationship between hardiness and coping with stress and so a cause and effect relationship may not be able to be established. Example: For example, we don’t know whether stress causes a lack of control or whether a lack of control causes an individual to feel stressed more often. Evaluation: This is a weakness because it means that researchers are unable to draw firm conclusions about the relationship between stress, individual differences and coping.