抑郁是最普遍的精神障碍，是导致残疾的主要原因，而不是其他任何疾病，也是直接和间接医疗费用的主要来源1。在没有实验室或影像学检查的情况下，通过临床访谈或自我报告量表引起患者症状是检测抑郁症并监测其对治疗反应的主要方法。

《患者健康问卷9项抑郁量表》（PHQ-9）于2001年首次发布，已在全球范围内传播，已被超过11,000篇科学引文并翻译成100多种语言。它已用于数百项基于临床和人群的研究中，并被纳入许多抑郁症指南中，并已在许多临床实践环境中实施。抑郁症筛查远未普及。但是，在出现这种情况时，PHQ-9处于领先水平2。

PHQ-9的国际普及可能是由于多种因素3。它的九项内容包括抑郁症的DSM标准，使其既严重又具有潜在的诊断性措施。总得分是项目得分的简单总和，切分易于记忆：5、10、15和20分别代表轻度，中度，中度重度和重度抑郁症状的阈值。与某些抑郁量表不同，PHQ-9可以免费用作公共领域的度量，并且许多翻译版本使全世界的人们都可以使用它。

PHQ系列包括几个缩写版本和同伴秤4。PHQ-2是一种超简短的筛选器，包括前两个项目（情绪低落和快感不足），这是抑郁症的核心标准。PHQ-8忽略了第九个问题，第九个问题询问“变得更好或以某种方式伤害自己”的想法。尽管通常认为它是自杀意念的筛查问题，但大多数积极的回答都代表了对这一复合项目的第一部分的认可（即，可以更好地摆脱死亡），而不是对自我伤害的积极思考5、6。因为第九项是最不常被认可的一项，所以PHQ-8和PHQ-9得分几乎相同，严重程度临界点7也是如此。

PHQ-8有时用于抑郁是次要结果而不是研究重点的研究中，在基于人群的研究中由非心理健康专业人员进行访谈，或者在患者报告临床结局（PROs）的临床环境中使用）是在上门拜访之外被捕获的，这导致在澄清对第九项的积极回应时出现延迟。

同伴量表评估抑郁的普通旅行者。P4是一项4项测量指标，用于评估认可PHQ-9 6第九项的个人的自杀意念。广泛性焦虑症7项（GAD-7）用于测量三分之一至一半的抑郁症患者中常见的焦虑症状。尽管最初是针对广泛性焦虑症开发的，但GAD-7还是针对恐慌症，社交焦虑症和创伤后应激障碍的有效筛查工具4。PHQ-15及其缩写版本（躯体症状量表-8，SSS-8）评估了抑郁症患者最常抱怨的身体症状的存在和严重程度，可能表示并发的躯体症状障碍和其他躯体化条件8。最后，PHQ-4由PHQ-2和GAD-2（GAD-7的缩写）组成，可作为对抑郁和焦虑以及一般心理困扰的超速筛查工具。可从www.phqscreeners.com获得PHQ系列秤，包括许多翻译版本。

在某些临床环境中，实际问题仍然限制了抑郁症和其他PRO措施的使用。临床医生或辅助人员的日常管理以及将分数手动输入到健康记录中通常需要花费时间。PHQ-9和其他专业人士通常不需要面试，而可以在上门服务之前或在家中使用多种模式（例如，基于纸质或基于Web的表格，iPad，应用程序）进行自我管理。然后可以将完整的PRO进行电子导入或扫描到记录中。

尽管一些指南提倡进行普遍性抑郁症筛查，但并未确定筛查的最佳频率。一种方法是对所有新患者进行筛查，然后每年对既定患者进行筛查。由于每次访视时对每个患者进行筛查的次数都过多，因此需要提醒何时进行筛查。

抑郁症措施的另一个关键作用是监测对抑郁症的积极治疗或在某些情况下注意等待的结果。同样，标记哪些患者需要随访PHQ-9则必须进行操作。

对PHQ‐9这样的量表的批评是，抑郁症不仅仅是一个数字。当然，仅抑郁评分不能单独产生反思性抑郁诊断或抗抑郁处方，而需要临床评估以确定是否已达到临床作用阈值。出现症状的时间长短，功能障碍的程度和患者的治疗偏爱，以及抑郁评分所表示的症状严重程度，共同决定了治疗决策，无论是心理治疗，药物治疗或观察等待。

纵向追踪抑郁症时，将PHQ-9得分与有关总体变化的问题结合起来很有用：“您的症状是否相同，好还是坏？”。抑郁评分与整体变化印象之间的不一致可能有几种解释，包括残余的躯体症状，如失眠或疲劳；并发症状，如焦虑或疼痛；其他医学或精神病合并症；压力或人际因素；或功能改进方面的滞后。

是否有必要采取普遍性的抑郁措施？事实证明，PHQ-9在竞争性抑郁量表上的表现与同类抑郁症相似或更好，包括在老年人，青少年，孕妇或产后妇女，不同种族/族裔群体，患有各种医学和精神疾病的患者等特殊人群中，以及整个临床环境。但是，有许多抑郁量表可以使用，并且有其支持者，并且越来越多地可以使用跨度量的跨步抑郁评分方法9。

将PRO纳入实践中，与衡量行为无关，而在于具体措施（假设它已得到充分验证）。它更多地是关于动词而不是名词。另一方面，使用共同的措施可以促进跨临床环境的交流，并避免巴别塔现象，其中针对同一情况使用不同的“语言”（即指标）。

在过去的二十年中，PHQ-9的使用与对抑郁症的日益认识相平行，抑郁症已成为国际公共卫生的重点，并且发现测量是朝着发现和改善管理迈出的第一步。用世界卫生组织前任主任陈M.的话来说，“问责就是计数；被测量的东西就完成了”。同上为抑郁症。

"点击查看英文标题和摘要"

Depression is the most prevalent mental disorder, a greater cause of disability than any other disease, and a major contributor to direct and indirect health care costs1. In the absence of a laboratory or imaging test, eliciting patient symptoms by clinical interview or a self‐report scale is the principal way to detect depression and monitor its response to treatment.

First published in 2001, the Patient Health Questionnaire 9‐item depression scale (PHQ‐9) has had global dissemination, with over 11,000 scientific citations and translations into more than 100 languages. It has been used in hundreds of clinical and population‐based studies, incorporated into numerous depression guidelines, and implemented in many clinical practice settings. Depression screening is far from universal; however, where it occurs, the PHQ‐9 is a leading scale2.

The international spread of the PHQ‐9 is likely due to multiple factors3. Its nine items comprise the DSM criteria for depressive disorders, making it both a severity and potentially diagnostic measure. The total score is a simple summation of item scores, and cut‐points are easy to memorize: 5, 10, 15, and 20 represent thresholds for mild, moderate, moderately severe, and severe depressive symptoms, respectively. Unlike some depression scales, the PHQ‐9 is free to use as a public domain measure, and the many translations make it accessible to populations around the world.

The PHQ family includes several abbreviated versions and companion scales4. The PHQ‐2 is an ultra‐brief screener that comprises the first two items (depressed mood and anhedonia), which are core criteria for depressive disorders. The PHQ‐8 omits the ninth item that asks about thoughts of “being better off dead or of hurting yourself in some way”. Although conventionally considered a screening question for suicidal ideation, most positive responses represent endorsement of the first part of this compound item (i.e., being better off dead) rather than active thoughts of self‐harm5, 6. Because the ninth item is the least frequently endorsed one, PHQ‐8 and PHQ‐9 scores are nearly identical, as are severity cut‐points7.

The PHQ‐8 is sometimes used in studies where depression is a secondary outcome and not the focus of the investigation, in population‐based studies where interviews are administered by non‐mental health professionals, or in clinical settings where patient‐reported outcomes (PROs) are captured outside of an office visit, causing delays in clarifying positive responses to the ninth item.

Companion scales evaluate common fellow travelers of depression. The P4 is a 4‐item measure that evaluates suicidal ideation in individuals who endorse the ninth item of the PHQ‐96. The Generalized Anxiety Disorder 7‐item (GAD‐7) measures anxiety symptoms that co‐occur in a third to half of patients with depression. Although initially developed for generalized anxiety disorder, the GAD‐7 is also an effective screener for panic, social anxiety, and post‐traumatic stress disorders4. The PHQ‐15 and its abbreviated version (the Somatic Symptom Scale‐8, SSS‐8) assess the presence and severity of physical symptoms that are the complaints with which depressed patients most frequently present, and may denote concurrent somatic symptom disorder and other somatizing conditions8. Finally, the PHQ‐4 consists of the PHQ‐2 and the GAD‐2 (abbreviated version of the GAD‐7) and serves as an ultra‐brief screener for depression and anxiety as well as general psychological distress. The PHQ family of scales, including many translations, are available at www.phqscreeners.com.

Practical issues still constrain use of depression and other PRO measures in some clinical settings. Routine administration by the clinician or ancillary staff and manual entry of scores into the health records require time that is typically unreimbursed. The PHQ‐9 and other PROs generally do not require an interview but rather can be self‐administered using a variety of modes (e.g., paper or web‐based forms, iPads, apps) before an office visit or while at home. Completed PROs can then be electronically imported or scanned into the records.

Whereas universal depression screening is advocated by some guidelines, the optimal frequency of screening is not established. One approach is to screen all new patients and then annually in established patients. Because screening every patient at every visit is excessive, reminders of when screening is due are required.

Another key role of depression measures is to monitor outcomes in response to active treatment of depression or, in some cases, watchful waiting. Again, flagging which patients require follow‐up PHQ‐9 administration must be operationalized.

One critique of scales like the PHQ‐9 is that depression is not simply a number. Certainly, a depression score alone should not generate a reflexive depression diagnosis or antidepressant prescription, but requires clinical evaluation to determine if the threshold for clinical action has been reached. The length of time symptoms have been present, the degree of functional impairment, and patient treatment preferences, combined with the severity of symptoms as denoted by the depression score, collectively inform treatment decisions, be it psychotherapy, medications, or watchful waiting.

When following depression longitudinally, it is useful to couple the PHQ‐9 score with a question about global change: “Are your symptoms the same, better, or worse?”. Discordance between the depression score and global impression of change may have several explanations, including residual somatic symptoms such as insomnia or fatigue; co‐occurring symptoms such as anxiety or pain; other medical or psychiatric comorbidity; stress or interpersonal factors; or a lag in functional improvement.

Is a universal depression measure necessary? The PHQ‐9 has generally been shown to be similar or superior in performance to competing depression scales, including in special populations such as older adults, adolescents, pregnant or postpartum women, diverse racial/ethnic groups, patients with various medical and psychiatric diseases, and across clinical settings. Nonetheless, a number of depression scales are available and have their proponents, and methods for cross‐walking depression scores across measures are increasingly available9.

Incorporating PROs into practice is less about the specific measure (presuming it is well validated) than the act of measuring; it is more about the verb than the noun. On the other hand, using a common measure may facilitate communication across clinical settings and avoid the Tower of Babel phenomenon wherein different “languages” (i.e., metrics) are used for the same condition.

Uptake of the PHQ‐9 in the past two decades has paralleled the increasing recognition of depression as an international public health priority, and the discovery that measurement is the first step towards detection and improved management. In the words of M. Chan, former director of the World Health Organization, “accountability means counting; what gets measured gets done”. Ditto for depression.