The Patient Health Questionnaire-9, or PHQ-9, is a brief, validated self-report tool that screens for depression and tracks symptom change over time. It distills the nine DSM criteria for major depressive disorder into nine plain-language questions, each scored from 0 ("not at all") to 3 ("nearly every day"), producing a total between 0 and 27. Because it is short, free, well-studied, and easy to repeat, the PHQ-9 has become one of the most widely used mental health instruments in primary care, behavioral health, and — increasingly — in pre-surgical workups.
Patients answer the questions based on how often each symptom has bothered them over the past two weeks. The patient drives the scoring, which makes the PHQ-9 useful for both an initial snapshot and longitudinal monitoring. A tenth, unscored question asks how much the symptoms have interfered with work, home life, and relationships, giving the score real-world context. Most patients finish in under three minutes, and the form can be completed on paper, by phone, or through a secure online intake before a telehealth visit.
PHQ-9 totals fall into widely recognized severity bands: 0–4 (minimal), 5–9 (mild), 10–14 (moderate), 15–19 (moderately severe), and 20–27 (severe). A score of 10 or higher has good sensitivity and specificity for major depression and typically prompts clinical follow-up. Item 9, which asks about thoughts of self-harm or being better off dead, is reviewed independently of the total — any non-zero response triggers a same-visit safety conversation, regardless of the rest of the score. Trend matters as much as the absolute number.
Surgical teams increasingly request psychiatric clearance before bariatric procedures, spinal cord stimulators, deep brain stimulation, vagus nerve stimulation, cosmetic surgery, and organ transplant. Clearance is not a rubber-stamp yes/no decision — it is a structured assessment of whether a patient can understand the procedure, tolerate recovery, and engage with the long-term behavior change many of these operations require. Untreated depression complicates each of those expectations, which is why a standardized depression screener belongs in every clearance workflow rather than being treated as optional.
Depression is associated with poorer post-surgical outcomes across multiple specialties: lower adherence to post-op protocols, slower wound healing, higher reported pain, more readmissions, and reduced long-term satisfaction with elective procedures. In bariatric and metabolic surgery, depressive symptoms can blunt the behavioral change that makes the operation work. In implantable devices like spinal cord stimulators or DBS, untreated depression can amplify the symptoms the device is meant to treat. Catching an elevated PHQ-9 score before the operating room — rather than after — gives the surgical and psychiatric teams time to optimize treatment.
At AlviPsych, the PHQ-9 is part of the universal screener set every patient completes before their virtual evaluation, alongside the GAD-7, AUDIT-C, and DAST-10. The score does not pass or fail a clearance on its own. Instead, it gives the evaluating psychiatrist a quantitative anchor: a baseline severity, a clear safety signal if item 9 is endorsed, and a number to revisit if the patient is reassessed before or after surgery. The clearance letter returned to the surgeon within 48 hours documents the score, the clinical interpretation, and any recommendations.
A practical advantage of a numeric screener is repeatability. When a patient's PHQ-9 drops from 16 to 7 between an initial evaluation and a pre-op recheck, that is measurable progress the surgeon can act on. When the score rises after surgery, it is an early signal for the primary care or psychiatric team to step in. Embedding the PHQ-9 in clearance — rather than treating it as a one-time gate — turns a screening tool into a longitudinal care instrument that follows the patient across the surgical journey.
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Mechanick JI, et al. Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures — 2019 update. Surg Obes Relat Dis. 2020.
Ghoneim MM, O'Hara MW. Depression and postoperative complications: an overview. BMC Surg. 2016;16:5.
