Löwe Bernd, Unützer Jürgen, Callahan Christopher M, Perkins Anthony J, Kroenke Kurt
Department of General Internal and Psychosomatic Medicine, Heidelberg University Medical Center, D-69120 Heidelberg, Germany.
Med Care. 2004 Dec;42(12):1194-201. doi: 10.1097/00005650-200412000-00006.
Although effective treatment of depressed patients requires regular follow-up contacts and symptom monitoring, an efficient method for assessing treatment outcome is lacking. We investigated responsiveness to treatment, reproducibility, and minimal clinically important difference of the Patient Health Questionnaire-9 (PHQ-9), a standard instrument for diagnosing depression in primary care.
This study included 434 intervention subjects from the IMPACT study, a multisite treatment trial of late-life depression (63% female, mean age 71 years). Changes in PHQ-9 scores over the course of time were evaluated with respect to change scores of the SCL-20 depression scale as well as 2 independent structured diagnostic interviews for depression during a 6-month period. Test-retest reliability and minimal clinically important difference were assessed in 2 subgroups of patients who completed the PHQ-9 twice exactly 7 days apart.
The PHQ-9 responsiveness as measured by effect size was significantly greater than the SCL-20 at 3 months (-1.3 versus -0.9) and equivalent at 6 months (-1.3 versus -1.2). With respect to structured diagnostic interviews, both the PHQ-9 and the SCL-20 change scores accurately discriminated patients with persistent major depression, partial remission, and full remission. Test-retest reliability of the PHQ-9 was excellent, and its minimal clinically important difference for individual change, estimated as 2 standard errors of measurement, was 5 points on the 0 to 27 point PHQ-9 scale.
Well-validated as a diagnostic measure, the PHQ-9 has now proven to be a responsive and reliable measure of depression treatment outcomes. Its responsiveness to treatment coupled with its brevity makes the PHQ-9 an attractive tool for gauging response to treatment in individual patient care as well as in clinical research.
尽管对抑郁症患者进行有效治疗需要定期随访和症状监测，但目前仍缺乏一种有效的治疗效果评估方法。我们研究了患者健康问卷-9（PHQ-9）对治疗的反应性、可重复性以及最小临床重要差异，PHQ-9是基层医疗中诊断抑郁症的标准工具。
本研究纳入了IMPACT研究中的434名干预对象，该研究是一项关于老年抑郁症的多中心治疗试验（63%为女性，平均年龄71岁）。在6个月的时间里，根据SCL-20抑郁量表的变化分数以及两次独立的抑郁症结构化诊断访谈，评估PHQ-9分数随时间的变化。在两个分别相隔7天完成两次PHQ-9评估的患者亚组中，评估了重测信度和最小临床重要差异。
以效应量衡量，PHQ-9在3个月时的反应性显著高于SCL-20（-1.3对-0.9），在6个月时相当（-1.3对-1.2）。对于结构化诊断访谈，PHQ-9和SCL-20的变化分数都能准确区分持续性重度抑郁症、部分缓解和完全缓解的患者。PHQ-9的重测信度极佳，其个体变化的最小临床重要差异估计为测量标准误的两倍，在0至27分的PHQ-9量表上为5分。
PHQ-9作为一种诊断工具已得到充分验证，现在已被证明是一种反应性良好且可靠的抑郁症治疗效果测量工具。它对治疗的反应性以及简短性使其成为在个体患者护理和临床研究中衡量治疗反应的有吸引力的工具。
