Joiner et al (1999)

• Aim: 

  To investigate the effects of dysfunctional thinking patterns on the development of depressive symptoms when exposed to a real-life stressor - Mid term exams.
• Research Method: 

  Prospective natural experiment.

  Selected 119 American university students (mean age 19) from an abnormal psychology course.
• Procedure:

  1. Assessed students 2 weeks before and 2 weeks after mid-term exams.
  2. Administered three tests using Questionaire:

  • Dysfunctional Attitudes Scale (DAS): Question them about perfectionism, need for approval, and need to impress - before exams only
  • Cognitive Checklist (CCL): Questions about Automatic thoughts linkined to depression - before and after exams
  • Beck Depression Inventory (BDI): Questions about Symptoms of depression - before and after exams
• Results:

  • Increased BDI scores in students with higher DAS scores who failed an exam.
  • No significant BDI score increase in students with higher DAS scores who performed well.
  • Students with lower DAS scores showed no depressive reactions, regardless of exam performance.
  • Correlation between higher depressive thinking pattern scores on CCL and increased BDI scores for students who failed.
  • No significant correlation between anxiety scores and BDI score increases.
• Conclusion: 

  Dysfunctional thinking patterns, combined with negative life events (exam failure), contribute to the development of depressive symptoms but only when we are exposed to stress.
• Strengths:

  1. Prospective design allowed for observation of changes over time - Measured twice a month. Which allowed control for biderectional Ambiguity.
  2. Use of standardized measures (DAS, CCL, BDI) enhances reliability. AS Standardized measures increase the consistency and comparability of results.
  3. Natural experiment setting increases ecological validity. Natural experiments observe real-life situations, making findings more applicable to everyday life.
  4. Supports the diathesis-stress model of depression.
• Limitations:

  1. Limited control over extraneous variables due to naturalistic setting which means the study have low internal Validity.
  2. Increase in depressive symptoms doesn't equate to clinical depression diagnosis. This limits the generalizability of findings to clinical populations.
  3. Sampling bias: American undergraduates studying psychology - Maybe being aware of Symptoms of depression can scew score on depression.
  4. Short-term study may not capture long-term effects or development of clinical depression.
• Overall Significance: 

  The study provides support for the cognitive vulnerability hypothesis and the diathesis-stress model in the development of depressive symptoms. It highlights the interaction between cognitive patterns and environmental stressors.