Earlier quoted context omitted.
Thank you. I am afraid I don't know and couldn't easily find any research. I did find this post, but it looks like SEO spam a little, and doesn't cite the essay claim: https://www.bookishelf.com/the-importance-of-information-ret... I'll ask Prof Roediger as we occasionally communicate and will aim to get back to you. However, I wouldn't be surprised if any correlation was not statistically significant.
One more thing. When you mentioned Test Anxiety it reminded me of frequent comments about anxiety during job interviews. I'm wondering if flashcards (or other retrieval practice) could help there too. Perhaps you can spin it into a product for professionals.
[edit: removed a point about variance which wasn't supported by more recent literate]
High stress (or anxiety) happens only periodically... like those job interviews you mention. It varies massively within individual subjects. There are some ways to reduce anxiety, but I wouldn't say anything has been conclusive yet. Here is an excerpt from my Dissertation about Test Anxiety... I found practise quizzes had a non-significant overall effect on Test Anxiety, and reduced only the "Tenseness" subscale of a relatively old measure sadly. The CTAS scale, referenced below, would probably be most useful for the job interview case.
"Test Anxiety is the additional stress felt when you must provide answers. It is prevalent, affecting students from preschool (McDonald, 2001) to taught university level, and across demographics (Beidel et al 1994; Beer 1991; Mwamwenda,1993). Prevalence is estimated at 20% (Ergene 2003) to 25% (Thomas et al, 2018) in current students. Test Anxiety often involves pressure, highlighting a social, non-genetic nature, and high variance is recorded between subjects (e.g. Keith et al 2010 longitudinal study showed low individual variation, but high between subjects variation). Overwhelming Test Anxiety significantly impairs wellbeing (Steinmayr et al., 2016). Interventions and online course design choices can markedly reduce Test Anxiety (Abdous, 2019). Unfortunately, few online learning studies record Test Anxiety, instead recording grade/score differences. Yet, Test Anxiety interventions are efficacious – e.g. "test-wiseness training" (Kalechstein et al., 1988), group counselling (Alkhawaja, 2013) and mindfulness training (Seidi & Ahmad, 2018). Research often classifies students into High and Low groups. There are disproportionately negative outcomes for High Test Anxiety students, whom more recently have been enrolled automatically in targeted interventions (e.g. Psychoeducation Bedel et al., 2020). Test Anxiety is related to Social Anxiety (Rothman, 2004; Sarason and Sarason, 1990). This manifests in a socialevaluative component, which appears in most scales, such as the Test Anxiety Inventory (TAI; Spielberger, 1980). TAI was designed for assessing children (Ludlow & Guida, 1991). Recent scales, including the Cognitive Test Anxiety Scale (CTAS; Cassady & Johnson, 2002), are adapted to university participants. An example CTAS item is "I feel under a lot of pressure to get good grades on tests.". CTAS has similar correlations with academic performance (Chapell et al., 2005) as those utilizing TAI (such as Hunsley, 1985), without the concerns of TAI applicability discussed in Szafranski (2012). Test Anxiety is typically construed as a trait under Latent state-trait theory, despite short term experimental intervention differences being observed (e.g. "looking ahead" immediately prior to testing in Mavilidi et al., 2014; or taking practice quizzes in Agarwal et al., 2014). Test Anxiety should not be confused with other forms of anxiety, such as General or Social Anxiety Disorder. Prevalence of anxiety is rising in college populations (Zagorski, 2018), as is loneliness, with 1 in 5 young people reporting having no close friends and feeling alone(n=2,522, Mental Health Foundation, 2019). Usage of social media is also associated with greater loneliness (Wohn & LaRose, 2014). However, artificially induced status updates have been shown to reduce it (Deters & Mehl, 2012), which aligns with status updates requesting academic support reducing Test Anxiety as found in Deloatch et al (2017) and findings linking higher wellbeing with greater academic outcomes (Public Health England, 2014). Research on social anxiety and social media is less clear, although recently Erliksson et al (2020) correlated greater internet usage and activity with increased social anxiety. Despite wide research on the negative aspects of social media usage (e.g. for university students, see Odacı & Kalkan, 2010) - little attention has been paid to online helping, which is fundamentally social."