The Implementation of the PHQ-9 to Assess and Diagnose Depression in New Patients in an Outpatient Psychiatric Practice

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The purpose of this evidence-based practice project was to evaluate the effectiveness of using the PHQ-9 tool to assess depression. Currently, no tool is being used to assess and diagnose patients with depression in an outpatient psychiatric practice. Instead, patients are diagnosed with depression based on a diagnostic interview with the healthcare practitioner (HCP). This study's objective was to improve the current clinical depression assessment and diagnosis practice by using the PHQ-9 screening tool to improve accuracy in diagnosing depression. The PHQ-9 is a reliable and valid tool for assessing patients in identifying factors predictive of depression, as well as a reliable measure of depression severity. These characteristics and its brevity make the PHQ-9 a valuable clinical and research tool in psychiatric outpatient practices. The data from this study supported the rationale for implementing this screening instrument in this outpatient psychiatric practice. Forty-nine new patients ages 18–54 years who were seeking treatment for depression at a psychiatric practice who had not been previously diagnosed with depression completed the PHQ-9 as well as the diagnostic interview with an HCP. The impact of the COVID-19 pandemic on patient depression was also explored. All participants were assessed using PHQ-9 and the diagnostic interview method. Data were analyzed using Stata 15 for descriptive and inferential statistics to examine the relationship between the two methods. Findings indicate that patients who expressed suicidal ideation during the clinical interview indicated the same on the PHQ-9. Results also show that PHQ-9 scores were significantly related to the severity of depressive symptoms. Finally, patients who indicated that COVID-19 had impacted them were significantly more likely to be assessed with major depressive disorder via the PHQ-9 instrument.

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  • 02/21/2024
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