Key study one: DiNardo (1998)
Aim: To investigate ‘excessive worry’ as a feature of Generalised Anxiety Disorder (GAD) and its relevance to phobias.
Participants:
- Patients who had been diagnosed with GAD and a control group of non-GAD patients (the original article does not state the number of participants involved in the research)
- The patients attended one of three clinics located in the USA
Procedure:
- This was a quasi experiment (i.e. patients either had or did not have GAD) with an independent measures design (i.e. each patient received one score per condition)
- The patients were interviewed using either the Anxiety Disorders Interview Schedule or the Structured Clinical Interview
- Each patient was interviewed twice, using the same questions, using the test-retest method
- The patients responded to the questions using a five-point rating scale which covered symptoms such as:
- Physiological responses to anxiety such as sweating
- Sleeplessness
- Excessive worry
- Excessive worry was measured in terms of how frequently the patients engaged in it on a daily basis, giving percentages to account for how much of each day was spent worrying (regardless of what the object of the worrying was)
Results:
- There was a significant difference in the percentage of worrying reported by the GAD patients than the non-GAD patients: 59.1% in the GAD patients compared to 41.7% of the non-GAD patients
- The non-GAD patients tended to report low levels of worry, in fact some of them reported that they did not worry at all (i.e. they spent 0% of the day worrying)
Conclusion:
- Excessive worry appears to be a key feature of GAD
- Excessive worry brings with it irrational thinking and cognitive distortions, both of which are symptomatic of phobias as well
Evaluation of DiNardo (1998)
Strengths
- The use of standardised rating scales and the test-retest method means that the study has good reliability
- The use of a control group means that results could be compared between groups to check for signs of GAD in the experimental group which increases the validity of the findings
Weaknesses
- The link between excessive worry, GAD and phobias is tenuous and does not really provide a conclusive answer to how the cognitive approach explains phobias
- The GAD patients may have given unreliable responses to the questions as a direct result of suffering from an anxiety disorder i.e. their ‘excessive worry’ could have led to them giving responses which were confused, untrue or which were based on a wish to please the researcher by doing the ‘right thing’
Can GAD be used to explain the ‘excessive worry’ element of phobias?