Age at implantation, learning, and cognition (Marschark et al., 2019)

<b>Purpose: </b>Age at cochlear implantation frequently is assumed to be a key predictor of pediatric implantation benefits, but outcomes related to learning and cognition appear inconsistent. This critical assessment examines relevant literature in an effort to evaluate the impact of age at implantation in those domains for individuals who received their devices as children.<b>Method: </b>We examined 44 peer-reviewed articles from 2003 to 2018 considering age at implantation and conducted statistical analyses regarding its impact on several domains, including literacy, academic achievement, memory, and theory of mind.<b>Results:</b> Across 167 assessments in various experiments and conditions, only 21% of the analyses related to age at implantation yielded evidence in favor of earlier implantation, providing greater benefits to academic achievement, learning, or cognition compared to implantation later in childhood. Among studies that considered cognitive processing (e.g., executive function, memory, visual–spatial functioning), over twice as many analyses indicated significant benefits of earlier implantation when it was considered as a discrete rather than a continuous variable.<b>Conclusion: </b>Findings raise methodological, practical, and theoretical questions concerning how “early” is defined in studies concerning early cochlear implantation, the impact of confounding factors, and the use of nonstandard outcome measures. The present results and convergent findings from other studies are discussed in terms of the larger range of variables that need to be considered in evaluating the benefits of cochlear implantation and question the utility of considering age at implantation as a “gold standard” with regard to evaluating long-term outcomes of the procedure as a medical treatment/intervention for hearing loss.<br><b>Supplemental Material S1.</b> Effects of age at implantation on literacy and academic achievement with age as continuous variable: Information provided by authors for cochlear implant (CI) users and correlation coefficients, if provided, as estimates of effect size.<br><b>Supplemental Material S2. </b>Effects of age at implantation on literacy and academic achievement with age as discrete variable: Information provided (cochlear implant [CI] users only) by authors and calculated effect sizes.<br><b>Supplemental Material S3.</b> Effects of age at implantation and cognitive functioning with age as continuous variable: Information provided by authors for cochlear implant (CI) users and correlation coefficients, if provided, as estimates of effect size. <b><br></b><b>Supplemental Material S4.</b> Effects of age at implantation and cognitive functioning with age as a discrete variable: Information provided by authors for CI users and calculated effect sizes.<br>Marschark, M., Duchesne, L., &amp; Pisoni, D. (2019). Effects of age at cochlear implantation on learning and cognition: A critical assessment. <i>American Journal of Speech-Language Pathology, 28,</i> 1318–1334<i>. </i>https://doi.org/10.1044/2019_AJSLP-18-0160<br>

**研究目的：** 人工耳蜗植入（cochlear implantation）年龄常被视为预测儿童人工耳蜗植入获益的关键指标，但与之相关的学习与认知结局却似乎并不一致。本批判性综述梳理相关文献，旨在评估植入年龄对儿童植入者上述领域的影响。
**研究方法：** 我们检索了2003年至2018年间发表的44篇关于植入年龄的同行评议论文，并针对植入年龄对读写能力、学业成就、记忆以及心理理论（theory of mind）等多个领域的影响开展了统计分析。
**研究结果：** 在不同实验与条件下的167项评估中，仅有21%与植入年龄相关的分析提供了支持早植入的证据——即相较于童年晚期植入，早植入能为学业成就、学习或认知带来更大获益。在针对认知加工（如执行功能、记忆、视觉空间功能）的研究中，当将年龄作为离散变量而非连续变量进行分析时，支持早植入具有显著获益的分析数量是后者的两倍以上。
**研究结论：** 本研究结果引发了方法论、实践与理论层面的诸多疑问，包括早期人工耳蜗植入研究中“早期”的定义方式、混淆变量的影响，以及非标准化结局指标的使用问题。本文结合本研究结果与其他研究的一致性发现，探讨了评估人工耳蜗植入获益时需纳入考量的更广范围变量，并对将植入年龄作为评估该手术作为听力损失医疗干预手段长期结局的“金标准”这一做法的实用性提出了质疑。
**补充材料S1：** 以年龄为连续变量时植入年龄对读写能力与学业成就的影响：作者提供的人工耳蜗植入（cochlear implant, CI）使用者相关信息，以及若有提供则用于估计效应量的相关系数。
**补充材料S2：** 以年龄为离散变量时植入年龄对读写能力与学业成就的影响：作者提供的仅针对人工耳蜗植入使用者的相关信息，以及计算得到的效应量。
**补充材料S3：** 以年龄为连续变量时植入年龄与认知功能的关系：作者提供的人工耳蜗植入使用者相关信息，以及若有提供则用于估计效应量的相关系数。
**补充材料S4：** 以年龄为离散变量时植入年龄与认知功能的关系：作者提供的人工耳蜗植入使用者相关信息，以及计算得到的效应量。
马沙克（Marschark, M.）、迪谢内（Duchesne, L.）与皮索尼（Pisoni, D.）（2019）。人工耳蜗植入年龄对学习与认知的影响：一项批判性综述。《美国言语语言病理学期刊》，28，1318–1334。https://doi.org/10.1044/2019_AJSLP-18-0160