Data from: Are they half as strong as they used to be? An experiment testing whether age-related social comparisons impair older people's hand grip strength and persistence

OBJECTIVE: To assess how age-related social comparisons, which are likely to arise inadvertently or deliberately during assessments, may affect older people's performance on tests that are used to assess their needs and capability. DESIGN: The study randomly assigned participants to a comparison with younger people or a no comparison condition and assessed hand grip strength and persistence. Gender, education, type of residence, arthritis and age were also recorded. SETTING: Age UK centres and senior's lunches in the South of England. PARTICIPANTS: An opportunity sample of 56 adults, with a mean age of 82.25 years. MAIN OUTCOMES MEASURES: Hand grip strength measured using a manual hand dynamometer and persistence of grip measured using a stopwatch. RESULTS: Comparison caused significantly worse performance measured by both strength (comparison =6.85 kg, 95% CI 4.19 kg to 9.5 kg, control group =11.07 kg, 95% CI 8.47 kg to 13.68 kg, OR =0.51, p=0.027) and persistence (comparison =8.36 s, 95% CI 5.44 s to 11.29 s; control group =12.57 s, 95% CI 9.7 s to 15.45 s, OR =0.49, p=0.045). These effects remained significant after accounting for differences in arthritis, gender, education and adjusting for population age norms. CONCLUSIONS: Due to the potential for age comparisons and negative stereotype activation during assessment of older people, such assessments may underestimate physical capability by up to 50%. Because age comparisons are endemic, this means that assessment tests may sometimes seriously underestimate older people's capacity and prognosis, which has implications for the way healthcare professionals treat them in terms of autonomy and dependency.研究目的：评估在评估过程中无意或有意产生的年龄相关社会比较，会对老年人在用于评估其需求与能力的测试中的表现产生何种影响。 研究设计：本研究采用随机分组设计，将参与者分配至与年轻人进行社会比较组，以及无社会比较对照组，并对其握力与耐力进行评估。同时收集参与者的性别、受教育程度、居住类型、关节炎患病情况及年龄信息。 研究地点：英格兰南部的Age UK（英国老年慈善组织）中心及老年人午餐聚会现场。 研究对象：通过便利抽样选取的56名成年参与者，平均年龄为82.25岁。 主要结局指标：采用手动握力计测量握力，使用秒表测量握力持续时长。 研究结果：无论以握力还是握力持续时长作为评估指标，社会比较组的表现均显著劣于对照组。其中握力方面，比较组为6.85kg，95%置信区间（95% CI）为4.19kg~9.5kg；对照组为11.07kg，95% CI为8.47kg~13.68kg，优势比（OR）=0.51，p=0.027。握力持续时长方面，比较组为8.36s，95% CI为5.44s~11.29s；对照组为12.57s，95% CI为9.7s~15.45s，OR=0.49，p=0.045。在校正关节炎、性别、受教育程度的差异，并依据人群年龄标准进行调整后，上述效应依然显著。 研究结论：鉴于在对老年人进行评估时，年龄比较及负面刻板印象激活的潜在可能性，此类评估可能会低估老年人的身体能力达50%之多。由于年龄比较现象普遍存在，这意味着评估测试有时会严重低估老年人的能力与预后情况，这将对医护人员在自主决定权与依赖性照护方面的决策产生影响。