Two Key Studies of a Cognitive Explanation of Phobias (DP IB Psychology)

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?

Key study two: Barrera & Norton (2009)

Aim: To investigate the quality of life as reported by patients suffering from GAD, a panic disorder and social phobia.

Participants:

• 67 patients who regularly attended the University of Houston Anxiety Disorder Clinic in the USA

• 17 of the sample had been diagnosed with GAD; 23 of the sample had a diagnosis of panic disorder and 27 of the sample had received a diagnosis of social phobia

• 33% of the sample were comorbid with major depressive disorder (MDD) and 51% of the sample were comorbid with anxiety

• The sampling method used was opportunity sampling

Procedure: 

• Each patient filled in the Quality of Life Inventory (QOLI)

• The QOLI measures positive mental health and happiness, resulting in an overall score based on (what they term) the "Sweet 16" areas that constitute quality of life, including love, work and play

• The QOLI score indicates a person’s overall satisfaction with life, based on responses to questions about how well the wishes, needs and goals of the respondent are being met.

Results: 

• The participants all scored lower on the QOLI  than a sample of non-anxious adults in the community who had previously been tested

• None of the three disorders appeared to bring less satisfaction than the others as all three showed similar levels of negative response i.e. GAD, panic disorder and social phobia appear to impact quality of life equally negatively

• The participants who were comorbid with MDD found that this impacted more negatively on their lives than those who did not also suffer from MDD (this was not true for the patients who were comorbid with anxiety)

Conclusion: 

• Having an anxiety disorder negatively affects quality of life

• There does not appear to be one specific anxiety disorder that has a more negative impact than others

Evaluation of Barrera and Norton (2009)

Strengths

• It is unusual and interesting to find a study which takes a cognitive approach to investigate phobias: this makes the findings useful as they can offer a fresh perspective on how to explain phobias (and, ultimately how to treat them) and the impact phobias have on the sufferer’s life

• The findings indicate that anxiety may be different in its manifestation than MDD as the comorbid patients with depression reported less satisfaction than the comorbid-with-anxiety patients: this reinforces the idea that phobias are a distinct type of anxiety disorder which require different treatment to MDD

Weaknesses

• The participants were asked to draw from their thoughts and feelings about quality of life which involves the operationalising of subjective variables which are open to interpretation which reduces the reliability of the findings

• The disparity between sample size per disorder means that there is a lack of uniformity in the research design which means that the findings lack generalisability i.e. the sample is not representative