Philip is a psychology student - AQA - A-Level Psychology - Question 2 - 2017 - Paper 2

Philip should indeed be concerned about the reliability of his friend's diagnosis. In psychology, the reliability of a diagnosis refers to the consistency of diagnostic results over time and across different evaluators.

Firstly, the DSM (Diagnostic and Statistical Manual of Mental Disorders) and the ICD (International Classification of Diseases) are often used as standard classification systems in diagnosing mental health disorders. However, there are inherent issues with these systems. For example, a diagnosis may vary depending on the clinician's interpretation and the subjective nature of reported symptoms, which can lead to inconsistencies.

Moreover, research indicates that individuals diagnosed with the same disorder can exhibit varying symptoms, leading to different treatment outcomes. Variability in diagnostic practices can also arise from cultural differences, subjective evaluations by different mental health professionals, and even the qualifications of those professionals. These factors can impact the reliability of a diagnosis, contributing to Philip's concerns about whether his friend's diagnosis is consistent and valid.

In summary, Philip's concerns about the reliability of his friend's diagnosis are valid given the potential for inconsistency in how mental health disorders are diagnosed.