How is Stress Measured?

SRRS 

• Self-report scales have been developed to measure the effect of life changes on stress levels and health
• The first was the Social Readjustment Rating Scale, created by Holmes and Rahe (1967)
• This measures the link between an accumulation of life changes and psychological or physical stress-related illnesses, by assigning life change units (LCU) to a list of 43 different life events (see the table below)
• Participants who are given the SRRS tick off all the life events they have experienced over the previous year and then add them up to gain a score that predicts their risk of stress-related illness in the next year or two
• 150 points or fewer means no stress-related health problems anticipated, while 300 points or more suggests an 80% chance of stress-related illness in the next year or two, suggesting that life changes are correlated with stress

The first ten items from the SRRS.

 Hassles & Uplifts Scale

• Kanner et al. (1981) developed a Hassles and Uplifts scale to measure the relationship between daily hassles and uplifts and ill health, arguing that too much focus had been placed upon life events as stressors and not enough upon the daily hassles that wear people down and create chronic stress
• The hassles part of the scale has 117 negative items covering all aspects of daily life and the uplifts scale has 135 positive items
• Daily hassles are defined by Kanner as those irritating, frustrating and distressing demands that we all face on a day-to-day basis, while uplifts are things like meeting friends, completing a task or getting enough sleep, which make us feel better

Excerpt from the hassles section of Kanner et al’s Hassles and Uplifts scale (1981).

Physiological measures 

• As stress affects the body so the the resulting physical changes may be measured: 

• • Blood and urine can be examined to assess the levels of stress hormones, such as cortisol and adrenaline 
  • Blood pressure also provides a reliable measure of stress, being higher when the person is stressed
  • Stress also increases respiration which changes the voice pitch and the micro tremors of speech muscles, so a stressed person may speak in a high and trembly voice
  • Skin conductance response (SCR) also known as galvanic skin response

Skin conductance response measures the skin’s resistance to electricity

• SCR readings are measured through use of a polygraph (‘lie detector’) machine 
• When individuals are stressed they sweat and this increases the skin’s ability to conduct electricity and thus increases the SCR score
• The polygraph also records blood pressure, pulse and breathing rate
• SCR has to be tested in stressed and unstressed conditions so comparisons can be made

A polygraph test measuring skin conductance response.

Research which investigates the measurement of stress

• Rahe et al (1970) tested the validity and reliability of the SRRS on over 2000 sailors who completed a life changes questionnaire prior to a cruise of from 6–8 months' duration, and found a positive correlation between their pre-cruise life changes and their number of reported illnesses throughout their time at sea
• DeLongis et al (1982) used Kanner’s Hassles and Uplifts scale to investigate the relationship between life events and daily hassles and uplifts and health and found that daily hassles were more strongly correlated with stress and ill health that were life events
• Villarejo et al (2012) found that SCR readings were able to detect participants’ different stress levels with a success rate of 76.5 per cent, supporting the idea of SCR being a valid method of measuring stress

Evaluation of the the measurement of stress

Strengths

• The results of  research into daily hassles may be used to formulate effective stress management and coping strategies to deal with stress and stress-related illnesses
• Stress management techniques such as biofeedback often use SCR measurements to indicate stress responses to help individuals control their stress levels

Weaknesses

• The SRRS does not distinguish between positive and negative life events and so it may lack internal validity as a measure of life events and stress
• SCR measurements can be affected by external factors like temperature and humidity, and internal factors like the taking of medications or alcohol, and so are not totally reliable

Link to Issues and Debates: 

The SCR is an example of biological reductionism as it just focuses on the physical symptoms as a valid measurement of an individual’s level of stress. It ignores the subjective experience of stress and individual differences between people. A more holistic approach would be to use SCR alongside self-reported measures of stress to create a whole picture of a person’s experienced stress.