Perski Olga, Lumsden Jim, Garnett Claire, Blandford Ann, West Robert, Michie Susan
Department of Behavioural Science and Health, University College London, London, United Kingdom.
UK Centre for Tobacco and Alcohol Studies, School of Experimental Psychology, University of Bristol, Bristol, United Kingdom.
J Med Internet Res. 2019 Nov 20;21(11):e16197. doi: 10.2196/16197.
The level and type of engagement with digital behavior change interventions (DBCIs) are likely to influence their effectiveness, but validated self-report measures of engagement are lacking. The DBCI Engagement Scale was designed to assess behavioral (ie, amount, depth of use) and experiential (ie, attention, interest, enjoyment) dimensions of engagement.
We aimed to assess the psychometric properties of the DBCI Engagement Scale in users of a smartphone app for reducing alcohol consumption.
Participants (N=147) were UK-based, adult, excessive drinkers recruited via an online research platform. Participants downloaded the Drink Less app and completed the scale immediately after their first login in exchange for a financial reward. Criterion variables included the objectively recorded amount of use, depth of use, and subsequent login. Five types of validity (ie, construct, criterion, predictive, incremental, divergent) were examined in exploratory factor, correlational, and regression analyses. The Cronbach alpha was calculated to assess the scale's internal reliability. Covariates included motivation to reduce alcohol consumption.
Responses on the DBCI Engagement Scale could be characterized in terms of two largely independent subscales related to experience and behavior. The experiential and behavioral subscales showed high (α=.78) and moderate (α=.45) internal reliability, respectively. Total scale scores predicted future behavioral engagement (ie, subsequent login) with and without adjusting for users' motivation to reduce alcohol consumption (adjusted odds ratio [OR]=1.14; 95% CI 1.03-1.27; P=.01), which was driven by the experiential (OR=1.19; 95% CI 1.05-1.34; P=.006) but not the behavioral subscale.
The DBCI Engagement Scale assesses behavioral and experiential aspects of engagement. The behavioral subscale may not be a valid indicator of behavioral engagement. The experiential subscale can predict subsequent behavioral engagement with an app for reducing alcohol consumption. Further refinements and validation of the scale in larger samples and across different DBCIs are needed.
与数字行为改变干预措施（DBCIs）的参与程度和类型可能会影响其效果，但目前缺乏经过验证的参与度自我报告测量方法。DBCI参与度量表旨在评估参与的行为（即使用量、使用深度）和体验（即注意力、兴趣、享受程度）维度。
我们旨在评估一款用于减少酒精消费的智能手机应用程序用户中DBCI参与度量表的心理测量特性。
参与者（N = 147）为通过在线研究平台招募的英国成年酗酒者。参与者下载了“少饮酒”应用程序，并在首次登录后立即完成该量表，以换取经济奖励。标准变量包括客观记录的使用量、使用深度和后续登录情况。在探索性因素分析、相关性分析和回归分析中检验了五种效度（即结构效度、效标效度、预测效度、增量效度、区分效度）。计算Cronbach α系数以评估该量表的内部信度。协变量包括减少酒精消费的动机。
DBCI参与度量表的回答可以用与体验和行为相关的两个基本独立的子量表来描述。体验性子量表和行为性子量表的内部信度分别较高（α = 0.78）和中等（α = 0.45）。无论是否调整用户减少酒精消费的动机，总量表得分均能预测未来的行为参与度（即后续登录情况）（调整后的优势比[OR]=1.14；95%置信区间1.03 - 1.27；P = 0.01），这是由体验性子量表（OR = 1.19；95%置信区间1.05 - 1.34；P = 0.006）而非行为性子量表驱动的。
DBCI参与度量表评估了参与的行为和体验方面。行为性子量表可能不是行为参与度的有效指标。体验性子量表可以预测与减少酒精消费应用程序的后续行为参与度。需要在更大样本和不同DBCIs中对该量表进行进一步完善和验证。
