Table_1_Determinants of physical activity behavior among older adults with subjective cognitive decline based on the capability, opportunity, motivation, and behavior model: mediating and moderating effects.DOC

BackgroundPA is vital for secondary prevention in older adults with subjective cognitive decline (SCD), but their physical activity (PA) levels are low, and the underlying interaction pathways among associated factors are poorly understood. This study aims to identify mediating and moderating effects of determinants on PA behavior in older adults with SCD using the capability, opportunity, motivation, and behavior model.
MethodsFollowing the STROBE checklist, we conducted a cross-sectional survey among 289 older adults with SCD. Path regression, mediation effects, and moderation effects were used to explore the associated factors of PA behavior and the associations among these variables.
ResultsThe prevalence of physical inactivity among older adults with SCD was high (40.3%). The path model fit indices were χ2/df = 1.145, GFI = 0.968, CFI = 0.988, and RMSEA = 0.022. Path regression revealed that frailty, physical and social support, PA motivation, and fall history had significant direct association with PA behavior. PA motivation not only partially mediates between frailty and PA behavior but also partially mediates between physical and social support and PA behavior. Additionally, fall history moderated the relationship between frailty and PA behavior.
ConclusionPA behavior in older adults with SCD requires improvement. Healthcare professionals should devise more effective interventions to boost PA behavior by enhancing motivation. Screening for frailty and addressing fall history, while providing sufficient physical and social support, is crucial.

背景 体力活动（Physical Activity, PA）对于伴主观认知下降（Subjective Cognitive Decline, SCD）的老年人群开展二级预防至关重要，但该群体的体力活动水平普遍偏低，且相关影响因素间的潜在交互通路仍未明确。本研究基于能力、机会、动机与行为模型，旨在探明各类决定因素对伴SCD老年人群体力活动行为的中介与调节效应。

方法 本研究遵循加强流行病学观察性研究报告规范（STROBE）清单，纳入289名伴SCD的老年受试者开展横断面调查。采用路径回归、中介效应与调节效应分析方法，探究体力活动行为的相关影响因素及各变量间的关联。

结果 伴SCD的老年人群体力活动不足患病率达40.3%。路径模型拟合指标为：χ²/df=1.145、拟合优度指数（Goodness of Fit Index, GFI）=0.968、比较拟合指数（Comparative Fit Index, CFI）=0.988、近似误差均方根（Root Mean Square Error of Approximation, RMSEA）=0.022。路径回归分析显示，衰弱、躯体支持与社会支持、体力活动动机及跌倒史均与体力活动行为存在显著直接关联。体力活动动机不仅在衰弱与体力活动行为之间起部分中介作用，同时也在躯体与社会支持和体力活动行为之间发挥部分中介效应。此外，跌倒史对衰弱与体力活动行为的关联具有调节作用。

结论 伴SCD的老年人群体力活动行为亟需改善。医疗卫生从业者应通过提升个体体力活动动机，制定更具针对性的干预方案以促进该群体的体力活动水平。筛查衰弱状况、干预跌倒史风险，并提供充足的躯体与社会支持，对改善该群体体力活动行为至关重要。