Centre for Research Excellence in Mental Health and Substance Use, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, Australia.
Centre for Mental Health Research, Australian National University, Canberra, Australia.
Qual Life Res. 2018 Sep;27(9):2453-2458. doi: 10.1007/s11136-018-1905-5. Epub 2018 Jun 5.
Recent US-based studies have utilised item response theory (IRT) to equate several self-report scales for depression and anxiety using the PROMIS depression and anxiety common metrics. The current study reports on the validity of the US-based equating procedures for the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7) and Kessler 6 psychological distress scale (K6) to equate scores in a large online sample of Australian adults.
Data comprised 3175 Australians recruited online. Each participant provided responses to the PROMIS depression and anxiety item banks, the PHQ-9, the GAD-7 and the K6. Two scoring methods were used to convert the scores on the PHQ-9, GAD-7 and K6 to the PROMIS depression and anxiety metrics. The converted scores were compared to the PROMIS depression and anxiety scores using intraclass correlations, mean difference, mean of absolute differences and Bland-Altman limits of agreement.
Statistically significant mean differences were identified in five out of eight equated scores, albeit the effect sizes were small (Cohen's d ≤ 0.25). The correlations were uniformly high (ICC ≥ 0.86). The mean of absolute differences between observed and equated scores for each metric and across scoring methods ranged between 4.23 and 5.33.
The results demonstrate the validity of generating PROMIS depression and anxiety scores from the PHQ-9, GAD-7 and K6 in an independent sample of Australians. The agreement between equated scores provides some assurance that researchers and clinicians can utilise the converted PHQ-9, GAD-7 and K6 scores on the PROMIS metrics without a substantial decrease in accuracy and precision at the group level.
最近的美国研究利用项目反应理论（IRT），使用 PROMIS 抑郁和焦虑通用指标，对几种抑郁和焦虑的自评量表进行了等效处理。本研究报告了基于美国的 PHQ-9、GAD-7 和 Kessler 6 心理困扰量表（K6）等效程序的有效性，该程序可对大量澳大利亚成年在线样本中的分数进行等效处理。
数据包括 3175 名在线招募的澳大利亚人。每位参与者都提供了 PROMIS 抑郁和焦虑项目库、PHQ-9、GAD-7 和 K6 的回答。使用两种评分方法将 PHQ-9、GAD-7 和 K6 的分数转换为 PROMIS 抑郁和焦虑指标。使用组内相关系数、均值差、均值绝对差和 Bland-Altman 一致性界限，将转换后的分数与 PROMIS 抑郁和焦虑分数进行比较。
在等效的 8 个分数中，有 5 个分数存在统计学上显著的均值差异，尽管效应量较小（Cohen's d ≤ 0.25）。相关性普遍较高（ICC≥0.86）。对于每个指标和两种评分方法，观察到的和等效分数之间的平均绝对差异在 4.23 到 5.33 之间。
结果表明，在澳大利亚的独立样本中，从 PHQ-9、GAD-7 和 K6 生成 PROMIS 抑郁和焦虑分数是有效的。等效分数之间的一致性为研究人员和临床医生提供了一些保证，即他们可以在不显著降低组内准确性和精密度的情况下，在 PROMIS 指标上使用转换后的 PHQ-9、GAD-7 和 K6 分数。
