Diagnosis plays a key role in identification of a disease, learn about its course, management and predicting prognosis. In mental health, diseases are often complex and coalesce of different symptoms. Diagnosing a mental health condition requires careful evaluation of the symptoms and excluding other differential disorders that may share common symptoms. Diagnose hastily can lead to misdiagnosis. A premature diagnosis or misdiagnosis has clear negative consequences. This is one of the problems related to mental health and one needs to optimize the diagnostic process to achieve a balance between sensitivity and specificity. Currently, the diagnosis of bipolar disorder (BD) is one of the major mental health conditions that is often misdiagnosed.

To differentiate BD from unipolar depression with recurrent episodes or with personality disorder (PD), especially type Cluster B – with features shared with mania/hypomania like mental instability or impulsivity, it is important to differentiate between a diagnosis and its comorbidity. BD is often misdiagnosed as personality disorder and vice versa specially when both are coexisting (almost 20% of patients with bipolar disorder type II are misdiagnosed as personality disorders). This is common especially with borderline PD, although in some cases the histrionic PD may also be misdiagnosed as mania.

Due to the inconsistency in patient care involving different psychiatrists combined with difficulty in obtaining a precise patient history and family history leads to loss of key information which in turn leads to misdiagnosis of the condition. The time delay in making the correct diagnosis cause by such inconsistencies may worsen the prognosis of the disease in the patient.