Alcohol and marijuana are the most commonly used psychoactive substances among young adults in the US (Schulenberg et al., 2021). Approximately 47 % of young adults report past-month alcohol consumption, with estimates slightly higher among college students compared to their non-college peers (SAMHSA, 2019). These data also show that nearly 23 % of young adults report past-month marijuana use, but in contrast to alcohol, marijuana use is higher among non-college young adults compared to college-aged peers. Alcohol and marijuana misuse are associated with negative consequences, including increased risk of injury or fatality, health problems, and developing comorbid psychiatric conditions, including substance use disorders (Hasin, 2018, White and Hingson, 2013). Given that young adulthood is a developmental period associated with academic and employment transitions (Cadigan et al., 2019, Roisman et al., 2004), effects of alcohol or marijuana use on absenteeism and engagement (i.e., defined here as attention and productivity) at school and work is of growing concern, particularly underlying mechanisms that contribute to poor outcomes.

It is well-established that the psychoactive properties of alcohol and marijuana produce cognitive deficits such as impaired attentiveness, concentration, and memory - cognitive skills important for engagement in a variety of settings, including school and work (Bourque and Potvin, 2021, Lisdahl and Price, 2012, Shillington and Clapp, 2001). Impairment can occur within hours of use and persist the following day and for weeks to months (Berre et al., 2017, Crean et al., 2011, Stavro et al., 2013, Wade et al., 2020). However, not all cognitive abilities are affected equally over time and depend on a complex interplay of factors, including age of use initiation, as well as quantity and frequency of use (Bourque and Potvin, 2021, Wade et al., 2020, Willford et al., 2021). For example, in a recent systematic review and meta-analyses, Gunn and colleagues (2018) examined associations between heavy drinking and next-day cognitive performance. Findings indicated that cognitive function, including sustained attention and psychomotor speed, and performance of daily tasks, such as driving, were impaired the day following heavy alcohol use. However, results were mixed for some cognitive functions such as working memory, and no effects were found for other cognitive functions such as divided attention. Overall, results revealed that heavy alcohol use impairs specific aspects of next-day cognitive function and performance. In a separate study, researchers reviewed acute and long-term effects of marijuana use, finding that attentional and information processing abilities may improve after a period of abstinence, whereas decision-making and risk-taking deficits may persist (Crean et al., 2011).

Although the short- and long-term effects of alcohol and marijuana on cognition is a complex interplay of biological and environment conditions, a growing body of research suggests alcohol and marijuana use are linked with decreased engagement and poor outcomes (e.g., job loss, school drop-out) at school and work (e.g., Arria et al., 2015; Gubbels et al., 2019, Okechukwu et al., 2019). Prior research suggests engagement is a multifaceted construct comprising at least two key components - cognitive engagement (e.g., attentiveness, motivation) and behavioral engagement (e.g., productivity, effort; Kahn, 1990, Wang and Eccles, 2013). Deficits in engagement associated with alcohol and marijuana use are predictive of poor outcomes, such as reduced motivation (Cherek et al., 2002, Lane et al., 2005) and decreased work performance (Bernerth and Walker, 2020, Thørrisen et al., 2019), lower grade point averages (Martinez et al., 2015, Pascarella et al., 2007, Paschall and Freisthler, 2015, Suerken et al., 2016), poor performance on assignments (Patte et al., 2017, Shillington and Clapp, 2001), dropping out of college (Arria et al., 2013, Fleming et al., 2012, Hunt et al., 2010), underemployment (Arria et al., 2013, Boden et al., 2017), and absenteeism (Schou & Moan, 2016). Together, these findings suggest that alcohol and marijuana negatively impact engagement broadly across settings and behavioral outcomes. While these are important findings, additional research to differentiate the effects of alcohol versus marijuana on the cognitive and behavioral components of engagement (i.e., attention and productivity) is warranted.

While the extant literature supports an association between substance use and academic and work-related outcomes, the bulk of research regarding these associations has come from cross-sectional research, which limits our ability to understand the temporal ordering of relationships (Lynskey and Hall, 2000) and impedes are our ability to develop adaptive prevention and intervention efforts. Additionally, few studies have simultaneously assessed the potential mechanisms (e.g., attentiveness, productivity) underlying these associations using methodologies capable of examining their unique contributions to outcomes across settings. Examining daily-level associations between substance use and academic- and work-related outcomes would allow better distinction between specific use-outcome associations, including their temporal ordering (Allen et al., 2020, Phillips et al., 2015). For instance, in a daily study of undergraduate students who use marijuana, marijuana craving was negatively associated with self-reported academic motivation in the moment (i.e., motivation to complete schoolwork) and with time spent studying at the next assessment point (i.e., later that day or the following day; Phillips et al., 2015). Further, average time spent smoking marijuana was negatively associated with cumulative GPA. In a similar daily study, college students were more likely to skip class and less likely to engage in schoolwork the day after engaging in heavy episodic (4+/5 + drinks for women/men) and high-intensity drinking (8+/10 + drinks for women/men), suggesting consequences extend to the following day (Allen et al., 2020).

Together, these studies highlight alcohol and marijuana use as important antecedents to engagement in tasks necessary for success, which has important implications for prevention and intervention efforts aimed at reducing risks associated with substance use. For example, better establishment of the temporal relationship between substance use and cognitive-behavioral outcomes could allow for adaptive, in-the-moment interventions to reduce risky or harmful use that could impede next-day engagement. However, more research is needed to better understand these complex and dynamic associations and potential mechanisms underlying these associations. The aims of the present study are to examine between- and within-person associations between 1) alcohol use and next-day absenteeism and engagement at school and work, and 2) marijuana use and next-day absenteeism and engagement at school and work among a community sample of young adults who use alcohol and marijuana. Consistent with previous research (Kahn, 1990, Wang and Eccles, 2013), we operationalized engagement as the combination of perceived attention and productivity, with attention representing one aspect of cognitive engagement and productivity representing one aspect of behavioral engagement. We hypothesized that at the between- and within-person level any and greater alcohol and marijuana use would be associated with increased next-day absenteeism and decreased next-day engagement at school and work.