Low and middle-income countries like India anticipate rapid population aging and increases in dementia burden. In India, dementia screening scales originally developed in other contexts need to be assessed for feasibility and validity, given the number of different languages and varying levels of literacy and education.

Using data from the Longitudinal Aging Study in India-Diagnostic Assessment of Dementia (N = 4,028), we characterize the performance of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). We described patterns and correlates of missingness, evaluated the psychometric properties of the scale, and assessed criterion validity against the Hindi Mental State Examination (HMSE) using linear regression.

Several IQCODE items had high levels of missingness, which was associated with urbanicity, respondent’s gender, and informant’s generation (same vs. younger generation). Full IQCODE scores showed strong criterion validity against the HMSE; each 1-point increase in IQCODE score was associated with a 3.03-point lower score on the HMSE, controlling for age, gender, and urbanicity. The statistically significant association between IQCODE and HMSE was stronger in urban than rural settings (p-value for interaction = 0.04). Associations between IQCODE and HMSE remained unchanged after removing the three items with the highest levels of differential missingness (remembering addresses and telephone numbers, ability to work with familiar machines, ability to learn to use new gadget or machine).

Findings raise questions about the value of including items with high proportions of missingness, which may signal cultural irrelevance, while removing them did not affect criterion validity.

印度等低收入和中等收入国家预计人口将迅速老龄化，痴呆症负担也会增加。在印度，考虑到不同语言的数量以及不同的识字和教育水平，最初在其他情况下制定的痴呆症筛查量表需要评估其可行性和有效性。

使用印度纵向老龄化研究痴呆症诊断评估 (N = 4,028) 的数据，我们描述了老年人认知衰退知情人调查问卷 (IQCODE) 的表现。我们描述了缺失的模式和相关性，评估了量表的心理测量特性，并使用线性回归评估了印地语精神状态检查（HMSE）的标准有效性。

一些 IQCODE 项目的缺失率很高，这与城市化程度、受访者性别和受访者的世代（同一代与年轻一代）有关。完整的 IQCODE 分数与 HMSE 相比显示出很强的标准有效性；在控制了年龄、性别和城市化的情况下，IQCODE 得分每增加 1 分，HMSE 得分就会降低 3.03 分。 IQCODE 和 HMSE 之间的统计显着关联在城市中比在农村中更强（交互作用的 p 值 = 0.04）。在删除差异缺失程度最高的三个项目（记住地址和电话号码、使用熟悉机器的能力、学习使用新小工具或机器的能力）后，IQCODE 和 HMSE 之间的关联保持不变。

研究结果对包含高缺失比例的项目的价值提出了疑问，这可能表明文化不相关，而删除它们并不影响标准的有效性。